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1. File Edit View Insert Window Help DEU 9 45a x a E amp amp DiExamples SpheresWalls Geometry xml v Tree View XSL Output B FileInput 4 FluidGrid B VoxelCompounds CompoundCount 5 Eompoundl ie ee D WalllsActive true SphereCount 2 oO Sphere CuboidCount 1 B Cuboid Name LowerHemisphere MaterialType Copper InitialTemperature 50 WallGrid Compound2 Compound3 Compound4 a Error List Dynamic Help Description File Line Column Figure 18 Assigning material properties to a wall object Compound1 gets the properties of Copper 7 Initial conditions CoPool is simulating time dependent processes Therefore initial conditions are very important Each variable which is taken into account requires an initial condition In our case the situation becomes even more complex because CoPool allows several sub rooms with different levels of liquid In other words the initial level of the liquid in the different sub rooms is one of the important conditions for the flow Additionally we have the following variables for the fluid e Velocity with components vx Vy Vz e Pressure p e Temperature I All of them need initial conditions In CoPool it is possible to have several wall objects In all wall objects we can solve the heat conduction equation This means that we also need initial 19 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM cond
2. fe es Organize v Include in library v Share with v Burn New folder v 1 O Ft Favorites is WE Desktop m COPREP_OUTPUT File folder l Downloads J results File folder i Recent Places DataBasexml XML Document 3 KB Geometry xml XML Document 17 KB Libraries _ logfile txt Text Document 82 KB Documents SubDomainFusion xml XML Document 1 KB aD Music x Figure 8 Content of the project directory after a simulation During the simulation a file named logfile txt is created It contains the main information of the simulation process 4 Starting the Xml editor using the button Edit The pre processor and the simulation code are controlled solely through the xml files though the user should carfully prepare these files Xml files can be Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM edited using any text editor More convenient is to use an Xml editor We propose to use XML Notepad 2007 If the xml editor is installed in the standard place it will be started automatically by pushing the button Edit and the corresponding XML Notepad GUI will appear separately The CoPool GUI has no influence on the default directories which are used in XML Notepad 2007 After initialization this tool proposes as default to open the file which was edited last r X XML Notepad gt el File Edit View Insert Window Help DEU A DiExamplesiCuboidiSubDomainFusion xml v Tree Vi
3. comment Here information required for the Lx 4 H O Ly 4 H D Lz 4 comment End information about characteristic length Transformation O 0 3 0 70 00 O Name RightCube amp MaterialType Copper InitialTemperature 60 BcType 4 Document AirParameters Figure 82 Parameters for an inclined rectangular pipe In this case the cuboids have originally different origins The sizes of cuboids are also different Because the second cuboid has the value Layers 1 then as result a cuboid with empty midlle part is obtained The wall mesh is created in the original coordinate system After that the mesh is transformed according to transformation parameters 0 0 3 0 7 0 0 0 It means that the new z axis is oriented in the direction 0 0 3 0 7 The origin of the coordinate system remains in the same place because all three components of the shifting vector are O The visualization of this wall compound with the corresponding mesh can be seen in Figure 83 Because the walls of this object are relatively large then this wall object can be resolved also on the fluid grid At the same time the representation is not with high accuracy If we filter color with the value 112 from the Fluid vtk then the following vall object can be obtained see Figure 84 How we can see then is the representation of the wall object in fluid grid not accurate But at least the wall object on the fluid grid had also in the middle part an
4. 13 1 Setting the same boundary condition on the whole boundary In CoPool it is possible to describe three different types of boundary conditions for the heat equation in walls The type of boundary conditions should be described for each wall compound individually using the xml element BcType The three possible conditions are e BcType 0 means that the air or liquid temperature close to the wall is used as the boundary condition for the temperature in this wall This feature can be convenient if only the heat conduction in walls is simulated e BcType 1 means that the wall is isolated No heat flux from outside Is available e BcType 4 is the default boundary condition In this case the heat exchange coefficient is estimated This kind of boundary condition is discussed in more detail in section13 2 If BcType is not explicitly defined for a compound this type of boundary condition is applied automatically 41 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM An example of a Geometry xml file with explicitly defined BcType can be found in Figure 38 In this case BcType 0 E X XML Notepad D SVN trunk CoPool examples SpheresWall Geometry xml lo IE File Edit View Insert Window Help DEU 9 4 Ea x A u DASVNitrunkiCoPoollexamples SpheresWall Geometry xml X Tree View XSL Output xml version 1 0 encoding utf 8 amp comment Can be copy pasted XML FileInput FluidGr
5. B ConfigFlow J General ConfigFor Flow DoSimulations true ResultsDirectory results VoxelColors GeomFile Fluid LeS comment MaterialName Water20 c StepSizeFile Fluid stepsize txt rs aaa Zoe ae a a Error List Denon Help Description File Line Column Figure 17 Assigning appropriate material properties to the fluid in this case Water20 If the input is correct the dependencies trom the data base file for the material Water20 will be taken for the simulation of the fluid flow and heat transfer 6 4 Assigning material properties to wall objects If the user is interested in the simulation of the heat transfer in walls for each wall object the material properties have to be assigned This is done in a similar way as for the fluid It is necessary to note down the value of the corresponding element in Geometry xml For each project several wall objects can be constructed Each wall object in CoPool is called a compound Each compound has an index and a name The file Geometry xml contains xml elements corresponding to each compound In each compound the element MaterialType should be available and should contain a name of a solid material In Figure 18 an example for the material type Copper of Compound can be seen 18 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM E x XML Notepad D Examples SpheresWalls Geometry xml oll amp
6. Compound Wallls Active e SphereCount Sphere Spherel e Origin DB Radius oO Sphere e Origin Radius e Layers CuboidCount J Cuboid Cuboid i Origin Coord ne CoordTwo i Height comment e Layers Name re MaterialType i InitialTemperature G BcType comment e Coordsys G SuppPointsE CellsR e SuppPointsT CellsT k SuppPointsP CellsP comment Radius comment Transformation J E Compound2 E E E Figure 79 Parameters for an inclined hemisphere true 00 0 13 000 11 ai 15 15 0 30 00 0 30 0 14 lt CoordThree gt 0 0 2000 lt CoordThree gt 1 LowerHemisphere Copper 60 4 lt BeType gt 0 lt BceType gt 0 value l isolation 4 spherical 0 15 70 0 3 13 3 14159 40 10 0 6 2824 25 Here information required for the 15 0 End information about characteristic length 00 30 70 00 The hemisphere is build by two spheres with radius 13 m and 11 m In Boolean operation also a cuboid in involved The grid for this hemisphere is 83 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM buildt in original soherical coordinate system according to support points and number of cells described in WallGrid This grid is transformed corresponding to transfomation parameters given under Transformations In this case the new z axis is oriented in direction 0 0 3 0 7 It
7. E X XML Notepad D Examples SpheresWalls Geometry xml loloj z File Edit View Inset Window Help DEU 9 er x A u amp DiExamples SpheresWalls Geometry xml v Tree View XSL Output 2 2 Compound3 a WalllsActive true cuboidCount 1 B Cuboid WallGrid Name LeftCube MaterialType Copper InitialTemperature 50 B Compound4 WalllsActive true cuboidCount 1 Cuboid GQ WallGrid coordSys rectangular 4 SuppPointsx 15 15 Cellsx 80 4 SuppPointsY 15 15 Cellsy 80 Error List Dynamic Help Saved Figure 44 Parameters to calculate the characteristic length for the case of a parallelepiped For the parallelepiped in this case Lx 4m Ly 4 m and Lz 2 m 13 4 Boundary conditions for the temperature on the contact faces with air in the case of BcType 4 The estimation of the heat exchange coefficient is done in the same way as in section 13 3 1 except that all material and flow characteristics have to be for air instead of fluid CoPool does not simulate air In the future all necessary information will be obtained from COCOSYS Until now the user can define appropriate conditions on air using input files In some of the next versions of CoPool the boundary conditions on the contact faces with air will be treated similarly as described in section 13 3 1 Recently in the case of contact with air the value of air temperature is take
8. ZA Fraunhofer ITWM CoPool User s Manual Aivars Zemitis Oleg lliev Konrad Steiner Tatiana Gornak Version 2 5 0 2 23 2012 Fraunhofer ITWM NNNNNNN s UI N 00 00 00 00 00 00 re U N 8 2 1 WO OOO NEE ee ee Seen N Moree Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM Authors and contributors Overview Installation Installation resources Installation procedure Workflow and using GUI of CoPool Tables used in CoPool Table with one constant value Table with several rows Table as a collection of pairs Managing material properties Data base information in the file DataBase xml Remarks about input values Assigning material properties for the simulation of heat and mass transfer in the fluid Assigning material properties to wall objects Initial conditions Initial values for air and liquid temperature Initial level of the liquid Air temperature Initial liquid temperature Initial values for the flow variables Initial values for wall temperatures Boundary conditions for the flow variables Boundary conditions for velocity Notation for faces Conditions on the free boundary Inlet part Conditions on walls Solid part Boundary conditions for the pressure Condition on the free boundary Inlet part Condition on the walls Solid part Sources and sinks Parameters characterizing sinks and sources Element TemperatureAvail Element HasToBeMoved Ele
9. 1 2010 0 1 e 10 0 4 m gt The value in the time table is increased by v Figure 12 Example of a table with 4 values as a collection of pairs 13 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM 6 Managing material properties For simulations of physical processes the material properties play a crucial role In CoPool there are two aspects of managing material properties e Collecting the material properties in the data base e Assigning the material properties to the fluid or walls via the Geometry xml Tile 6 1 Data base information in the file DataBase xml The simulation code is organized in such a way that all material parameters needed for simulations are coming from a data base Material properties for fluids or walls should be collected under appropriate material names and should be stored in the file DataBase xml Formally different data base files could be used but for each project only one data base Tile can be taken into account The file Geometry xml has to contain the name of the data base file in this case DataBase xml Until now simulations can be done with only one liquid which has certain material parameters collected under an appropriate name in the data base Tile In Geometry xml there is an element XML Document DataBaseFile which should contain the complete path to the data base file or simply the data base s file name if it is directly in the project directory i x XML Notep
10. A Zemitis O Iliev T Gornak and B Schmidtmann 2012 The pipe object with wall grid can be seen in Figure 73 Because the wall of the cylinder is thick then it can be fully resolved also on the coarse fluid mesh Figure 74 This figure can be obtained trom the Fluid vtk using theshold value 115 for the upper and the lower bound It can be seen 7 heat Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM that the mapped pipe on the coarse fluid mesh has also empty internal part It means that the fluid can flow through this rough pipe DB CylinderOivtk Figure 73 Pipe object represented on the wall grid 78 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM DB FIUIA VTK Zz x Figure 74 Resolved pipe on the fluid grid 20 1 2 A pipe with thin wall The other pipe in this example is taken with a thin wall see Figure 75 The name of this object is SmallCylinder 79 H E Compound4 ee oO Compounds EE Compounds H D WallIsActive CylinderCount cylinder a 5 Cylinderl H Origin H CenterLine H D Radius E oer i Height c Layers Eh Eylinder2 H Origin co CenterLine H c Radius eo Height H Layers WallGrid H D CoordSys E SuppPointsR ee cellsk H SuppPointsT a CellsT aes SuppPointszZ eg Cellsz isisi amp coment Aq CenterLine F Radius Aq Height zu amp comment N amp Transformation oa i
11. D Gas Fey Tree View XSL Output 3 XML comment Constant table in old format Add 0 Scale 1 Value 37 Error List Dynamic Help Description File Line Column Figure 10 An example of a table with constant value Table with several rows In this case it is necessary to specify the number of rows using the keyword N and then include new keywords for each row Row1 Row2 RowN Between these tags in the xml file the ti and f should be written In Figure 11 an example of a table of this kind is shown It is used for the description of the intensity of a sink In this example the table arguments are time steps and the function values are intensities of the sink at different time moments i X XML Notepad D Examples SpheresWalls Geometry xml lolol amp File Edit View Insert Window Help Ed gt ax HH amp S DiExamplestCuboid Geometry xml X Tree View XSL Output 4 N a comment time table for sink instensity with N rows Scale 1 comment The value in the time table is scaled by Scale Add 0 comment The value in the time table is increased Dy H O Rowl 0 1 Row2 2000 1 Row3 2010 0 3 0 oui f 0 BL amp comment Intensity table time sec value m3 sec Figure 11 Example of a table with 4 rows old format 12 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM Here the parameters Scale and Add have neutral values i e the value in the
12. FileInput Document DataBaseFile DataBase xml ConfigFlow BoundFlow oO BoundaryPart G Inlet NumbSimpleCond 2 Condi EQ Cond2 Variable E Btype 0 comment Value 0 Zero flux 1 Non zero flux 2 CondForVelocity true Velocity Outlet Solid NumberOfWallParts Error List Dynamic Help Figure 35 Setting the boundary conditions for the temperature on the free boundary The principal meaning is only given by the parameter Btype If this parameter is set to O then the air temperature in the corresponding sub room is used for the boundary condition If Btype is set to 1 then the isolation 3 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM condition for the temperature in the liquid will be applied on the free boundary i e no heat conduction between water and air If Btype 4 then in this case heat exchange between liquid and air is simulated Here the same method is used for calculation of heat exchange condition as in the case of wall and liquid see section 13 3 1 Instead of wall parameters here the liquid parameters and properties are used The characteristic length is calculated as square root of the corresponding free surface area Remember CoPool is not simulating the heat conductivity in air Only prescribed air temperature and velocity values can be taken in to account The possibilities of defining time tables for air are described in
13. The line below the last coordinates specifies the number of time moments In the example of Figure 64 there are 3 time moments Underneath the time moments should be written To separate the time moments one or more spaces should be used In our example the results for the given point will be written at 500 1000 and 2000 seconds The simple existence of the file Tilecoordtime txt is not enough to get information of the solution in special points It is absolutely necessary to include a special points section in the file Geometry xml where FileCoordAndTime has to have the correct name Tilecoordtime txt In Figure 65 an example of the output file specialpoints txt created by CoPool can be seen _ pepontstgotpne Ee MM cS File Edit Format View Help Information about special points All units in SI Pl coord 1 0 8 0 5 Time sec P1 Vx P1 Vy P1 Vz P1 P P1 T 500 0 000695558 0 000241151 0 00059082 11 8319 11 3471 1000 0 000435769 0 000431099 0 00187901 18 6238 11 7461 Figure 65 specialpoints txt for the special point defined in Figure 64 In the case of several monitoring points similar output is prepared for each monitoring point 69 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM 17 2 Monitoring points for walls Monitoring points in wall parts can be managed similar to monitoring points in the fluid part The main difference is the position of the
14. Windows 7 C ca Data D tu Network Folder SpheresWalls Select Folder Cancel Figure 2 Window for choosing the project working directory in this case D Examples SpheresWalls The selected project directory should be seen on the GUI Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM 1 CoPool ZA Fraunhofer DiExamplesiCuboid Figure 3 The selected directory D Examples Cuboid can be seen on the GUI It is important to remark that the initial content of this directory consists of two Tiles e DataBase xml e Geometry xml In general the project directory can contain any other files During the pre processor step and the simulation step additional files will be generated If the directory contains files with the same names as generated files then the old ones will be overwritten without warning The files generated by CoPool will be discussed later The file DataBase xml contains all material parameters which are needed for the simulation Geometry xml contains all information which is required for the geometry construction the mesh generation and the solver These two Tiles should be available in every project directory used with CoPool The geometry construction is described in the pre processor s manual A detailed description of the information needed for the solver will be discussed later in this document The simulation code requires data which d
15. fs Dp HE A 9 ote i Sac Replace Paste 2 I m Picture Paint Dateand Insert drawing time objet y co tO Ho oO e jamb i j N eS eS gt D un j oO SI ET SE Ry Ce 15 1 1 170 2 number of special points 00 3 0 7 0 7 3 10 number of time moments 10 15 100 200 300 400 500 600 700 800 100 y Figure 68 specpCylinder txt containing coordinates and time moments of special points In this example there are two monitoring points with Cartesian coordinates 0 O 3 and 0 7 0 7 3 The evaluation of the results is done at ten different time moments namely for t 10 15 100 200 300 400 500 600 700 and 800 seconds 17 3 Check the correctness of the special points The user might be interested in knowing how close the defined monitoring points are to the nearest voxel center Such information can be found in the file logfile txt During the initialization process the code is looking for the closest voxel to each special point After the voxel is found the following intormation is written in logfile txt lt PointName gt lt x gt lt y gt lt z gt distance to the voxel lt distance gt In this case lt PointName gt will be either SpecialPointsWall or SpecialPointsFluid lt x gt lt y gt lt z gt are the three coordinates of the special point which were read from the corresponding file mentioned in FileCoordAndTime lt distance gt
16. is the distance m of the special point to the closest voxel center An extract of the file logfile txt for the example 72 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM mentioned in section 17 2 2 can be found in Figure 69 File Edit Options Buffers Tools Help DEB HAI KHERSKE SpecialPointsWall 0 0 3 distance to the voxel 0 194826 SpecialPointshall 0 7 0 7 3 distance to the voxel 0 324925 m tau 1 ime 1 tau 1 f logfile txt 47 174 0 Text Fill Figure 69 An extract from the file logfile txt If the distance to the closest voxel is larger than the step size it is necessary to check the coordinates of the point Also it can happen that the coordinates define a point outside the wall or fluid domain 18 Special simulation regimes By including appropriate parameters in Geometry xml it is possible to run simulations that exclude some parts of the simulation code 18 1 Simulating the fluid flow without taking into account the walls In case the walls are thermally insulated there is no reason to calculate the heat conductivity in walls To ignore the wall elements for this calculation an element called TakeWallsIntoAccount which can be either true or false is included in Geometry xml It is placed in the section XML Document ContigFlow General In Figure 70 an example is shown where the parameter
17. the orientation of the normal vector of the wall surface element must be determined The normal vector points into the fluid If the angle between the vertical and the normal vector is less than 45 i e if the normal is in region a in the blue part in Figure 41 then the wall surface area element is approximately horizontal ceiling If the angle is between 45 and 135 the normal vector is in region b in the red part in Figure 41 then the element is approximately vertical side wall If the angle is between 135 and 180 the normal vector is in region c in the green part in Figure 41 then the element is approximately horizontal floor Figure 41 Schematic picture of possible orientations of normal vectors Now the characteristic geometric length L must be determined for heat transter This parameter is used in formulas 13 1 and 13 2 For vertical cuboid or cylinder faces L is the height of the surface For horizontal cylinder or sphere faces L is the diameter For horizontal cuboid faces L is the smaller one of the lengths of the two sides This information must be generated by the user and stored in Geometry xml Tile for each wall mesh More in details this procedure is described in section 13 3 2 45 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM Here Vertical means the direction along the gravitational acceleration The characteristic length L refers to the full dimension of the geometric
18. 2000 1 2010 0 1 e 10 0 a oe 4 Ww j FF Error List Dynamic Help Description File Line Column Figure 29 An example with a source description The source temperature in this case is taken constant and equal 10 C The intensity of this source is detined as a table using pairs 30 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM 9 1 Parameters characterizing sinks and sources 9 1 1 Element TemperatureAvail This parameter can be removed in the future It indicates if the temperature for this construct is available or not Until now it is necessary to set this parameter to true if we want to define a source negative intensity and it should be set to false if we want to define a sink positive intensity In this case the temperature will not be used even if some value for the temperature is available in the xml tile 9 1 2 Element HasToBeMoved As CoPool can start simulations with empty sub rooms it is necessary to be able to move a Source to the water level Each sink or source has the parameter HasToBeMoved If the value is set to true then this sink or source will always be mapped to the upper layer of the liquid In other words the sink or source will always be moved together with the free boundary It means that also a shifting in x y plane will be done If shifting in z direction alone leads to some position outside the fluid domain If HasToBeMoved has th
19. Name fj MaterialType H 0 InitialTemperature H D BeType u Fcomment f y Document H E AirParameters Figure 75 Parameters for the pipe with a thin wall Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM Start charact length 0 11000 SmallCylinder Copper lt BcType gt 0 lt BcType gt 0 value 1 isolation 4 _ In this case the interior radius of the pipe is 0 4 m and the outer radius is 0 5 m It means that relatively not only the wall is thin but also the radius of the pipe is small The Transformation parameters are O 11000 It means that the rotation of the z axis is done in yz plane by 45 80 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM Figure 76 Pipe with a thin wal represented on the wall grid This pipe can no be resolved on the coarse fluid grid If we search for the representation of this wall in the fluid mesh Fluid vtk color 116 then we find only one cell see Figure 77 Figure 77 Respresentation of the thin pipe on the fluid grid 81 20 1 3 Results Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM In similar cases it can happen that maybe few cells or no one cell will be marked as this pipe It means that such object will not have practically direct influence to the flow At the same time the heat exchange between liquid and wall object is taken into account The example InclinedCylinders CoPool version 2 5 consi
20. Schmidtmann 2012 CoPool Pre processor s manual CoPool version 2 5 0 Kaiserslautern Fraunhofer ITWM Elsner N 1973 Grundlagen der Technischen Thermodynamik Berlin Akademie Verlag
21. and the desired time moments for the measurements The user can choose themselves which name to use In the example this file is called tilecoordtime txt e OutputFileName name of the text file where the output will be written e nVariables contains the number of variables the user is interested in The maximal number is 5 e Variable contains the name of the variables Usable names are Vx Vy Vz P T These names are fixed and case sensitive 17 1 2 Preparing FileCoordAndTime The information about the coordinates of the desired special points and the time moments of the eval Uation of the results have to be included in a text file here called filecoordtime txt This file has to be in the project directory i e in the same directory as the Geometry xml The syntax of this Tile is shown in Figure 64 68 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM 1 number of special points 2 9 08 70 53 3 number of time moments 500 1000 2000 Figure 64 An example showing the structure of filecoordtime txt The first line contains the number of special points which will be used In this case there is only one monitoring point In the following lines the coordinates of the points must be given In each line the three coordinates x y z for a point separated by space s Here we have only one line containing the coordinates 1 1 8 0 5 since we are dealing with only one monitoring point
22. and the wall s 63 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM 16 1 Simulation results for the fluid part All simulation results for the fluid flow are stored in the directory results in files called Ttlow vtk In dependence of the chosen output time interval DToutput_sec cf section 14 1 the result files are created each time actual time exceeds a multiple of the output time interval The file name is created as a concatenation of the word flow the actual time loop index and vtk The solution for the temperature in wall parts is stored in the same manner and at the same time moments There is no special management of the output for walls The settings for fluid part are used 16 1 1 Scalars related to the fluid flow At the above described time moments CoPool creates a file flow vtk containing the following scalars for each fluid voxel e The temperature of the liquid T C e The reduced pressure p Pa pressure without hydrostatic pressure e The scalar value Sinks If this parameter is equal to 0 no sink or source is positioned in this voxel If there is a sink or source this parameter contains values 100 Plots op s B ST EEK A Sa Add Operators Delete Hide Show Draw Variables Boundary i Contour gt i 4 Sa Curve gt i Filled Boundary Histogram gt MX Label gt lin mesh I BA Mesh Molecule gt p
23. can be observed in Figure 89 At this moment the liquid is flowing from the middle chamber to the next one 90 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM Cc Time 750 025 Figure 89 Temperature in walls and in the liquid The liquid part is represented together with the actual fluid grid For a better visualization a clip operator is applied In Figure 90 the liquid level in the middle part has achieved the holes in the outer boundary Therefore the artificial sink and source are switched on which simulate the overflow to the outer liquid chamber Time 3200 04 Figure 90 The solution after 3200 seconds The liquid achieves the level of holes and the overflow to outer part is switched on In Figure 91 the solution after 7200 seconds can be seen At this moment the liquid level in the outer chamber achieves the liquid level in the middle part It means that the middle part and outer part are direcly connected by the liquid layer and artificial source and sink at this place are not needed 91 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM Time 7 200 05 Figure 91 Solution after 7200 seconds The liquid level in outer part becomes equal to the liquid level in internal part More detailed information about simulated processes can be taken trom the Geometry xml SubDomainFusionOrig xml and files generated by pre processor 21 Bibliography A Zemitis O Iliev T Gornak and B
24. can be placed everywhere because they are not directly connected to CoPool 3 2 Installation procedure The installation procedure is the same as Tor usual Windows installation files It should be started from some normal user account and not from the account of an administrator Click the icon of the file and follow the installation wizard During the installation the administrator s password will be required Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM After a successful installation a CoPool shortcut should appear on the user s Desktop Additionally one or several icons of directories should appear Each one of these directories corresponds to an example These directories can be copied to some other place and the user can test the program using these examples In the case of a normal user there are no differences on which accessible drive the project directory is created If the user has administrator rights then in some cases it can happen that the code has not the rights to write in the corresponding directory In this case the code breaks down At first it is necessary to test the code putting the project directory on the public space drive D 4 Workflow and using GUI of CoPool Shortly summarized the work with CoPool can be divided into the following three steps e Decision about project directory e Geometry creation and mesh generation e Simulations and viewing the results The workflo
25. emty space It means that the liquid can flow trough this wall object 86 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM Figure 83 Inclined rectangular pipe represented on the wall grid Figure 84 Representation of the rectangular pipe on the fluid grid 8 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM 20 2 3 Results In this example is simulated the case if at the beginning all walls are at 60 C and then the liquid source with 10 C starts to work The liquid Tills the container and there is a heat exchange between the liquid and the wall objects In this example the liquid level is not perpedicular to the actual z axis of the hemisphere Therefore it is interesting to observe how the cooling of the hemisphere happens Ivan 89 997 Min 415 Figure 85 Temperature distribution in walls at appropriate liquid height the liquid is not shown The plane of the liquid can not be exactly mapped to the spherical surface which axis is not perpendicular to the fluid plane Now we can observe stairs on the spherical mesh These structures correspond to the actual liquid level Similarly the rotated cuboid has difficulties with the representing of the flat liquid level which is not alligned with axis of the cuboid 88 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM 20 3 Model reactor directory ModelReactor code version 2 5 In this example a complex geo
26. fluid colors but also overlapping colors colors between 201 and 299 This means that these objects overlap with each other Two objects are overlapping if their boundaries contain the same overlapping color Some rules concerning overlapping colors which the pre processor should follow automatically e Overlapping colors should only be used on the boundary layer of the wall object The boundary layer is identified by the additional voxel layer which is above the internal voxels 61 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM e Overlapping colors are used for boundary voxels that are inside some other wall object i e that are overlapping From the color list we can see that Wall1 overlaps with Wall4 the common overlapping color is 202 and that Wall2 overlaps with Wall4 the common overlapping color is 201 Figure 56 Overlapping parts color 202 red on Wall4 UpperHemishpere caused by the intersection with Wall1 RightCube A cut of the hemisphere has been done therefore the internal color of the hemisphere green can also be seen The blue boundary layer indicates the contact with fluid color 3 Figure 57 Overlapping parts color 202 red on Wall1 RightCube caused by the intersection with Wall 4 UpperHemisphere A clipping tool has been used so the internal color green of Wall1 can also be seen The blue boundary layer indicates the contact with fluid
27. height of cylinders is 6 m it would be also possible to choose the support points between 7 1 far Compounds H WalllsActive e CylinderCount Cylinder Cylinderl e Origin e CenterLine Radius Height k Layers Cylinder2 i Origin CenterLine_ Radius Height Layers J WallGrid cu Coordsys e SuppPointsk cellsR k SuppPointsT CellsT e SuppFointsZz cellsz comment e CenterLine F Radius e Height amp comment Transformation Name k MaterialType e InitialTemperature BcType comment a Compounds Document I FL Bee dee ds ELE fe Figure 72 Parameters of the pipe with a thick wall true oboo Oo 5 i H 00 1 eo 5 I co j a cylindrical 0 0 0001 2 2 5 1 20 3 0 6 2830 20 3 2 40 Start charact 100 0 8 5 end charact 1 019090 0 Cylinder Copper 60 4 lt BeType gt 0 lt BcType gt length length 0 value 1 isolation 4 There is a new child of WallGrid called Transformation inside the xml document The six numbers have the following meaning The first three numbers give the orientation of the new z axis In the example the z axis is rotated in xz plane and the rotation angle is 45 The next three numbers give the position of the origin of the new coordinate system In the example the origin remains at the same position More information about transtormation parameters can be found in
28. pre processor generates different files on the base of the file Geometry xml Those output files are stored in a sub directory of the project directory named COPREP_OUTPUT see section 4 One type of the generated files are vtk files which can be visualized using a visualization tool as Paraview or Visit The generated vtk files in the COPREP_OUTPUT directory can be divided in two groups The file Fluid vtk contains information about the fluid mesh All other vtk files correspond to wall compounds and describe wall geometries It is important to understand that in COPREP_OUTPUT written vtk Tiles do not give the exact size of objects They contain additional layers of voxels The real size of the object can be seen if the filter for internal color is applied in the visualization software The internal voxels have to be covered with at least one layer of boundary voxels These boundary voxels will be used for creating of boundary faces in the discretized geometries Boundary voxels must characterize the medium of the boundary In the case of walls boundary voxels must contain the color of corresponding fluid sub room In the case of overlapping boundary parts the boundary voxels positioned in some other wall objects must contain a special color for overlapping parts Information about wall colors can be found in WallColor xml from COPREP_OUTPUT 54 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM If we read the
29. task Therefore in CoPool there are some tools which allow simplifying this work 1 For each sink a parameter SubRoomColor should be prescribed This color must correspond to the sub room classification written in SubDomainFusion xml 2 Each sink should have a coordinate list which is stored in the parameter CoordinatesO The parameter should contain 3 numbers They are corresponding to the coordinates in x y and z direction Now different situations can occur e Assume that HasToBeMoved is set to false In this case the position of the sink is fixed If the coordinates of the parameter CoordinatesO correspond to a point in the sub room with color SubRoomColor then 33 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM the sink is positioned in this place If the coordinates of sink from CoordinatesO do not correspond to some internal point of the sub room with the color SubRoomColor the sink is shitted horizontally to the closest point of the sub room with color SubRoomColor If it is not possible then the sink will not work In any case the sink can only work if the water level is above its position The sink will remain at this point independent of the free boundary level For sources the intensity is negative the shifting also in the vertical direction will happen if the original position is above the actual liquid level see 9 1 2 In this case the shifting is not only inside the sub room with color SubRoomCo
30. time table is scaled by 1 and is increased by 0 The table consists of N 4 rows In Row1 the function value is set to 1 and starts at time O until the time marked in Row2 here 2000 seconds is reached then the function value is changed to the intensity of Row2 here again 1 until the time marked in Row3 here 2010 seconds is reached Then the intensity is set to 0 For higher time values the intensity remains 0 Using this format it is also possible to define constant tables If the table consists of only one row then for all argument values the function value will be the same 5 3 Table as a collection of pairs In the third format all rows are stored in one element called Pairs The user himself has to take care that the appropriate number of pairs ti fi is noted down for this element The entire table should be written as a sequence in the following way t4 f to f t3 f T 3 ta la fa The code automatically estimates the number of pairs and creates the necessary table As an example we rewrite the table seen in Figure 11 using the new format r X XML Notepad D Examples SpheresWalls Geometry xml o amp z File Edit View Insert Window Help bea 9 a x BEE D ExamplesiCuboid Geometry xml X Tree View XSL Output comment lt N gt 4 lt N gt a comment time table for sink instensity with N rows Scale 1 amp comment The value in the time table is scaled by Scale 4 Add 0 Pairs 0 1 2000
31. transfer a characteristic water flow velocity along the surface must be estimated In most cases the velocity component normal to the wall surface element is close to zero The absolute velocity in the center of neighboring fluid cell uaps vu v w is a suitable estimate The Reynolds number is Re abst 13 2 Vv The Nusselt number for forced convection heat transfer is given by the Colburn correlation Nuyore 0 036 Re Pr 3 The actual Nusselt number is the maximum of the values for natural and forced convection Nu max Nunat N Ugrel The heat transfer coefficient is calculated as amp Nu L The simple correlations for natural and forced convective heat transfer given above were taken from Elsner 1973 13 3 2 Prerequisites for the calculation of a During assembling the matrix for heat conductivity in walls the code should go through all wall voxels As can be seen from equations for the calculation of a given in section 13 3 1 the global information of the object characteristic length L is required The user should give information needed to calculate L 4 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM This information must be explicitly written in Geometry xml for each wall object Here the question could arise why the user shall write this information explicitly The answer is the following Each wall object can be constructed using different basic prototypes and Bo
32. und Wirtschaftsmathematik ITWM 15 1 2 Walls in fluid mesh The flow simulation can only be done if all boundary conditions are defined correctly In the file Fluid vtk it is possible to check which boundary parts are really resolved on the fluid mesh Wall voxels have colors starting with 110 Wall colors used are described in the file WallColors xml which can be found in the directory COPREP_OUTPUT In the case of SpheresWalls this file should contain the following information see Figure 50 F X XML Notepad D Examples SpheresWalls COPREP_OUTPUT WallColor xml o amp e File Edit View Insert Window Help Ub Ba ax Bien D Examples SpheresWalls COPREP_OUTPUT WallColor xml v Tree View XSL Output WALLXML A EQ WallMatrix Zeosnsnnnunnsnnnsnnunnnonsnnnnnsennnnns WallCount PLTITPPPFPPPPPPPPPEPFFFPEFEFFFPRPPPPEPLPERFFFFFFPFRERFFRFPERFFEFFTPFFERRFRPPRFFEFEPPFFEFFFRRRRPREPFPRFFFFFFFFPRPFRFFRLRREEFFTRFPRFERFFPRPEEEEPUFFFERRRERRPPPPFRFRFRFFFFFFRERFRRPPERFEEFFTPRPRRFFRFRRPPEREEFFEFFFFRERRPPFPFRERFFFFTFRN HE w ran l Ww 1 Error List Dynamic Help Figure 50 Structure of the file WallColor xml In this example there are five wall compounds For each wall compound the information about used colors in the compound is stored For example Wall4 contains the following information Figure 51 i X XML Notepad D Examples SpheresWalls COPREP_OUTPUT Wal
33. 48 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM e Height gives the height of the cylinder An example of data for a cylindrical object can be seen in Figure 43 a X XML Notepad D Examples SpheresWalls Geometry xml le amp amp File Edit View Insert Window Help Ub Ba 42a 4X a HE DiAExamples SpheresWalls Geometry xml v Tree View XSL Output CompoundCount O Compoundi B Compound2 B Compound3 B Compound4 O Compounds WallIsActive CylinderCount Cylinder 1 Fe E LU uee Bante T cCoordSys SuppPointsR CellsR SuppPointsT CellsTt SuppPointsZ Cellsz comment s CenterLine_P Radius Height amp comment m amp MaterialType InitialTemperature 0 Error Liet gimmie Figure 43 Information needed to calculate the characteristic length of cylindrical objects Here the CenterLine_P lt 0 0 1 gt Radius 0 8 m and Height 4 m e Information for parallelepipeds In this case the three parameters Lx Ly and Lz are required The actual version of the pre processor cannot generate inclined boxes This means that the faces of the parallelepiped have to be parallel to the coordinate planes An example of parameters for a parallelepiped can be seen in Figure 44 49 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM
34. Btype 0 amp comme Value 0 Zero flux 1 Non zero flux 2 Error List Dynamic Help Figure 26 Conditions for velocity components on the free boundary Heretofore the mass balance is calculated based on the activities of sinks and sources In the case of overflow artificial sinks and sources are defined automatically This is just one example which already shows that changes in the Inlet conditions can lead to some problems in the simulation algorithm 8 1 3 Conditions on walls Solid part Up to now two types of boundary conditions for the velocity components can be applied on solid walls If Btype is set to O then an explicit value for the velocity component is expected Inserting the Value 0 corresponds to the no slip boundary condition The other possibility is to set Btype 3 This boundary condition corresponds to the slip condition The normal velocity component will be set to 0 and a zero gradient condition for the two velocity components parallel to the wall will be applied 8 2 Boundary conditions for the pressure 8 2 1 Condition on the free boundary Inlet part As mentioned above this condition should not be changed The boundary type Btype is O on the free boundary the pressure value should be directly 28 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM assigned The value for the pressure must be set to 0 The corresponding fragment of the xml document can be seen in Fi
35. Color 40 20 2 NroomsConnected 2 4 SubRoom1 2 0 20 20 4 SubRoom2 3 0 20 20 4 m p Figure 47 Content of SubDomainFusion xml for the example SpheresWalls It can be seen that three sub rooms with sub room colors 2 3 and 4 exist The sub rooms with color 2 and 3 are separate they are connected by the sub room having the color 4 which is a link layer Using the file Fluid vtk we should be able to visualize these three sub rooms It is important that the threshold values are set between 2 and 4 see Figure 48 55 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM F Threshold operator attributes o amp ss For individual threshold variables Variable Lower bound Upper bound Show zone if default min max Part in range Compound 100 2 4 Part in range vY Add variable Delete selected variable For all threshold variables Output mesh is Zones from input Point mesh Make default Load Save Reset Apply Post Figure 48 Threshold settings in Visit DB Fluid vtk Figure 49 Fluid voxels in the example SpheresWalls obtained by Visit using threshold and clipping Now all internal fluid voxels can be seen The blue voxels correspond to the sub room 2 the green ones to the sub room 3 and the red part is the link layer sub room 4 connecting both sub rooms 56 Fraunhofer Institut fur Techno
36. Document Error l ist Dunamia Ualn Figure 66 SpecialPointsWall as a child element of WallGrid of the element Compound5 In Figure 66 an example of how to include the element SpecialPointsWall is shown As usual for xml tiles the order of the child elements is not Important Now the element SpecialPointsWall will be explained in more detail This element contains four child elements 70 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM e FileCoordAndTime file name containing the coordinates of the monitoring points and the desired time moments for the measurements The syntax of this file is exactly the same as for the fluid part e OutputFileName name of the text file where the output will be written e nVariables contains the number of variables the user is interested in For wall objects this value has to be 1 because in walls only one variable is available e Variable1 has to have the fixed value T in walls we solve only the equation for temperature An example of an element SpecialPointsWall can be seen in Figure 67 XML Notepad D SVN trunk CoPool examples SpheresWall Geometry xml olg x File Edit View Inset Window Help D pH 2 amp Xx 8 i DN SVNitrunk CoPool examples SpheresWall Geometry xml v Tree View XSL Output SpecialPointswWall FileCoordAndTime specpCylinder txt k OutputFileName OV Oy b f B 4
37. O SubRoom3 Error List Dynamic Help Figure 36 AirParameters for 3 sub rooms In this case air parameters are prepared for 3 sub rooms Attention The number of sub rooms should exactly correspond to the total number of sub rooms in SubDomainFusion xml This means that before the 39 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM element AirParameters is prepared it is necessary to run the pre processor and to find out the number of sub rooms by studying the Tile SubDomainFusion xml see section 15 1 1 12 2 Structure of AirParameters for a given sub room For each sub room we have to describe the air temperature and we can also describe the velocity values in the given sub room All parameters should have the same structure The child elements of SubRoom are the following e RoomColor contains the color of the given sub room e Temperature contains the time table for the air temperature in the sub room e Velocity contains again 3 child elements Vx Vy and Vz Each of these elements contains time tables for the velocity components 12 3 Time tables for the air temperature and the air velocities For the input data the different tables presented in section 5 are used In Figure 37 the time table for the temperature and for the velocity component Vx of the sub room with room color 4 can be seen E x XML Notepad D SVN trunk CoPool examples SpheresWall Geometry xmi o am
38. SpheresWalls Geometry xml lee sz File Edit View Insert Window Help JE Bas Ax E j E D Examples SpheresWalls Geometry xml Te StepSizeFile Fluid stepsize tat amp comment stepsmall tzt stepsizes tzt FlowParam H D NumbOfSinks 1 H E Sinkl H E Sink2 E D amp D TurbParameters El TurbViscosity H D N 1 jf commen table for viscosity in dependence from H M Scale Hf Add HM Rowl 2 Vertical H r N nif commen H D Scale H D Add H Rowl i m SteppingParam H 0 LinSolvParams lt Variables gt lt T gt lt InitialValue gt 60 lt InitialValue _ Figure 33 Example of using turbulent viscosity 10 2 Turbulent heat conductivity for the liquid The element TurbParameters can contain a second child element called TurbConductivity see Figure 34 3 XML Notepad D SVN trunk CoPool examples Spheres Geometry xml e xX File Edit View Insert Window Help D REH 2 amp X amp a a DASVN trunk CoPoollexamples Spheres Geometry xml v Tree View XSL Output 9 5 Sink A pw sink O TurbParameters ee en ae 4 TurbViscosity E 4 TurbConductivity Figure 34 TurbConductivity as a child element of TurbParameters TurbConductivity contains again two child elements Horizontal and Vertical Similarly as in the case of turbulent viscosity each of them has to be a table defining the values of conductivity which will be added to the original conductivity found in the data base 36 Fr
39. TakeWallsIntoAccount is set to false 73 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM Ru x XML Notepad D Examples SpheresWalls Geometry xml o z File Edit View Insert Window Help EU 9 9 428 X A u amp SI Di Examples SpheresWalls Geometry xmi X Tree View XSL Output xml version 1 0 encoding utf 8 amp comment Can be copy pasted O XML B FileInput Document m DataBaseFile DataBase xml EQ ConfigFlow General c ConfigFor Flow 9 TakeWallsIntoAccount false iin DoSimulations true QO Das nltaNnirartnr r results 4 mw p Error List Dynamic Help Figure 70 Switching off the influence of walls In this case the code runs faster Also relationships between fluid cells and wall cells will be not estimated in this case Remark By now this parameter has no influence on the pre processor That means that the pre processor will create all information concerning walls whether TakeWallsIntoAccount is set to true or false 18 2 Simulating the heat conductivity in walls without flow simulation It is possible too to simulate only the heat conduction in walls without any flow simulation In this case the different air temperatures in the sub rooms are used as boundary conditions for the wall elements Each sub room can have a different air temperature which can be prescribed by the user in the file SubDomainFusion xml Thi
40. UI Therefore the user should carefully edit the necessary input files before starting the simulation By now there are three xml files that the user should work with DataBase xml Geometry xml and SubDomainFusion xml These documents are explained in detail in the sections 6 till 18 20 Advanced examples 20 1 Example with rotated and shifted pipes directory InclinedCylinders code version 2 5 20 1 1 A pipe with thick wall In this example is shown how the rotation and shifting of wall objects can be realized in the case of cylindrical wall objects This example is stored in the folder Examples InclinedCylinders Software version 2 5 Here two different pipes are included In one case the wall of the pipe is thick enough 1 m and it can be resolved by the fluid mesh The corresponding wall parameters can be seen in Figure 72 The pipe is created using two cylinders The first one has the radius 2 m and the Layers 1 The second has the radius 1 m and the Layers 1 As result we obtain a pipe with the wall thickness 1 Im It is important to remember that the wall mesh is generated allways in the original coordinate system In this case the cylindrical coordinate system is used Because the axis of the cylinder Centerline_P is oriented in the negative direction then also the support points in z direction are chosen in the negative 70 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM domain 9 2 Because the
41. ad D Examples SpheresWalls Geometry xml o amp amp File Edit View Insert Window Help Ua 4 amp Ga x A u E DAExamplestCuboid Geometry xml X Tree View XSL Output xml version 1 0 encoding utf 8 comment Can be copy pasted XML FileInput Document DataBaseFile DataBase xml EQ ConfigFlow _ a fCanarsi m r v Finur Figure 13 Location of the Data base file in Geometry xml The data base is organized in such a way that users can always add new materials or parameters 14 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM The document DataBase xml contains the element NumberOfMaterials which contains the total number of included materials in the data base Material numbers start from O and for each material there is an corresponding xml element The structure of a data base can be seen in the Figure 14 RR _ m _ x XML Notepad D Examples SpheresWalls DataBase xml lo amp amp File Edit View Insert Window Help DEU Ea gt DAExamples CuboidiDataBase xml v Tree View XSL Output en or nae TTA EEE A B Materials NumberOfMaterials 5 O Materialo B Materiall B Material2 O Material3 B Material4 FF Figure 14 Structure of the material data base used in CoPool Each material has an element MaterialName which contains the string with the name of the material for example Water20 Additionally there is a Boolean type e
42. arameters are obtained trom xml files It is not important in which sequence the keywords for parameters are ordered in the xml file only the hierarchy of data is essential e Incase that parameters are defined as tables and in the corresponding xml file no input data can be found then these parameters are generated with O values e Inthe code during the discretization process the parameter values will be controlled Zero values in some cases can stop the code It is not allowed to have a O density or O Cp In these cases the code stops with the message Please check the values in the data base 6 3 Assigning material properties for the simulation of heat and mass transfer in the fluid In Geometry xml there should be an element XML Document ConfigFlow General MaterialName This element should contain a valid material name which is defined in data base file e g DataBase xml If this is not the case an error will occur An example how to use fluid properties for the material Water20 can be seen in Figure 17 17 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM r X XML Notepad D Examples SpheresWalls Geometry xml o amp 2 File Edit View Insert Window Help DEU 9 42 8 amp x aA H amp Di Examples SpheresWalls Geometry xml v Tree View XSL Output xml version 1 0 encoding utf 8 comment Can be copy pasted XML D FileInput B Document DataBaseFile DataBase xml
43. aunhofer Institut fur Techno und Wirtschaftsmathematik ITWM 11 Boundary conditions for the temperature of the liquid CoPool simulates temperature in liquid and also in walls It is necessary to prescribe boundary conditions for temperature in both cases Here we discuss boundary conditions for the temperature from the liquid side The liquid has contact to walls and to the air in corresponding sub rooms The liquid can have a contact to the air on the upper liquid surface This part we call also as a free boundary 11 1 Boundary conditions for the temperature on the free boundary Recent versions of CoPool can use only two types of boundary conditions for the temperature on the free boundary Either the air temperature in the corresponding sub room is directly used as a boundary condition for the temperature in the liquid or the isolation condition is applied Those boundary conditions are described in Geometry xml in the section XML Document BoundFlow BoundaryPart Inlet It is necessary to find conditions for the variable T An example of a Geometry xml file can be seen in Figure 35 Here the condition for the temperature T is placed in the element Cond2 F x XML Notepad D Examples SpheresWalls Geometry xmi o amp File Edit View Insert Window Help D RHI aa x amp D Examples SpheresWalls Geometry xml v Tree View XSL Output xml version 1 0 encoding utf 8 comment Can be copy pasted 3 XML 4
44. boundary conditions of the liquid and also for the walls Each liquid level knows which air temperature is above the liquid 7 1 3 Initial liquid temperature For each sub room we can prescribe different initial temperatures of the liquid In Figure 22 we see an example where the temperature in sub room 1 is 30 C 23 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM in sub room 2 the temperature is 20 C and in sub room 3 we have 40 C DB flow0 vtk Cycle 0 Time 0 Pseudocolor Var T Ee S AXIS Sred 2 108 e Figure 22 Example with non zero initial height in the link layer and different temperatures in sub rooms Here the liquid levels of sub room 1 and 2 have been set to 6 Starting at the deepest point i e at 14 the liquid should be filled till 3 but we can see that if the prescribed deepness of sub rooms is larger than the real deepness the underlying sub rooms are simply filled up 7 2 Initial values for the flow variables The initial values for the flow variables as the velocity components vx Vy Vz and the pressure p are automatically set to 0 Until now the user cannot change these initial values In the model we work with the reduced pressure i e without hydrostatic pressure The full pressure is the sum of the calculated pressure and the hydrostatic pressure 7 3 Initial values for wall temperatures The walls must be described as separate wall objects separate co
45. change the following parameters e DTmin_sec is the minimal time step in seconds which is used in simulations The minimal time step is applied in the beginning of simulations and then the time step is continuously increased to the value DTmax_sec During the simulation process the time step can be changed back to the minimal value in special cases For example if a new sub room should be filled 51 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM e DTmax_sec is the maximal time step in seconds which is used in simulations e DTouput_sec is the time interval in seconds between the outputs of result files e Tend_sec is the time in seconds when the simulations stops e MaximumStepCount is the total number of time steps which are allowed If the actual time step count becomes larger than this value the simulation is stopped In the actual version the user should not change the values for e AdaptTimeStep currently only false is allowed e CFLcoeff 14 2 Element LinSolvParams In this element only two parameters are available 14 2 1 Relative residuum LSTol LSTol is the tolerance of the relative residuum at which the linear solver delivers the numerical solution of the linear system For all linear systems the same parameter is used default value 1 e 9 The corresponding data structure in Geometry xml can be seen in Figure 46 52 Fraunhofer Institut fur Techno und Wirtschaftsmathe
46. color 3 The correctness of the boundary colors for all wall objects is an important prerequisite for the simulation of heat conductivity in walls Therefore boundary colors should always be veritied 62 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM 16 Simulation results The output files of the results are saved in vtk format They are stored in the project directory in a sub directory called results In this directory we find two types of vtk Tiles results concerning the fluid flow and results concerning the wall parts Results concerning the fluid flow are called flow vtk For the fluid part we will always just get Tluid vtk files no matter how complex the container geometry Is The solution method for the heat conduction in walls is based on domain decomposition methods This means that we solve separate heat conductivity problems in each wall part Therefore the solution is written in separate Tiles for each wall part having names like compound_name vtk A complete impression of the solution can be obtained when the results of the fluid flow part and the wall parts are visualized at the same time as it is done in Figure 58 2 Axis Figure 58 Temperature in the fluid and in the wall parts obtained by loading all vtk solution files The visualization tool Visit allows building correlations between different solutions It also allows creating a movie for the heat exchange between the liquid
47. containing the exact data of some given points This possibility can be used by adding some elements in the file Geometry xml plus creating a special text file which should be prepared by the user 17 1 Monitoring points for fluid In the case of monitoring points in fluid regions the necessary changes that have be done in Geometry xml are explained below as well as the special text file that has to be created 6 17 1 1 Element SpecialPointsFluid in Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM Geometry xml If the evaluation of the result in some special points is desired it is necessary to add the new Element SpecialPointsFluid in Geometry xml It has to be placed at the position XML Document SpecialPointsFluid An example of an included Element Speci Figure 63 Tree View XSL Output comment XML 4 FileInput Document amp ConfigFlow BoundFlow NumberOfWallParts SpecialPointsFluid Th p alPointsFluid is shown in Can be copy pasted 4 FileCoordAndTime filecoordtime txt OutputFileName nVariables Variablel Variable2 Variable3 Variable4 Variables H H HE eooe specpoints txt 3 VX Vy Vz P T Figure 63 Element SpecialPointsFluid included in Geometry xml In the element SpecialPointsFluid the following child elements appear e FileCoordAndTime file name containing the coordinates of the special points
48. e e the initial level of liquid in each sub room e the temperature of the air in each sub room e the initial temperature of the liquid in each sub room if the initial level of the liquid was not zero For all these values appropriate default values are already set Further down we will discuss the file SubDomainFusion xml in more detail DataBase xml and Geometry xml are not modified during the pre processor step Attention The pre processor creates a new SubDomainFusion xml file each time it is run The old one is automatically overwritten If the user changed some default values in SubDomainFusion xml then this information will be lost after rerunning the pre processor Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM 3 Starting simulations using the button Simul If the pre processor had no errors during the geometry generation then it is possible to start simulations Additional requirements are the existence of DataBase xml and that SubDomainFusion xml contains correct data If this is fulfilled the simulation can be started by pressing the button Simul On the GUI the status message Running should appear CoPool a Fraunhofer Figure 7 GUI during the running process The results of the simulation are stored in the sub directory results After a successful simulation the structure of the project directory should be as follows
49. e value false and the intensity Is positive real sink then this sink will work only if it is underneath the liquid level If HasToBeMoved has the value false and the intensity is negative real source then two different scenarios at each time step can happen e Ifthe original position of this source is below the actual tree boundary then the source remains at the original position e Ifthe original position is higher as the actual free boundary then the source will be projected to the free boundary There are no restrictions to this parameter in the case of several sub rooms and several liquid levels 31 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM 9 1 3 Element CountSinksOfThisType This parameter was used in earlier versions Currently the value of this parameter must be set to 1 9 1 4 Element Temperature This parameter has a meaning if TemperatureAvail is set to true In the case of sources the source temperature is used in the heat equation for the fluid The source temperature can be constant or also time dependent In the case of a constant source temperature it is possible to assign the temperature value to the sink with appropriate index directly In the case of the Sink1 we should assign the temperature value to the xml element Document ConfigFlow General FlowParam Sink1 Temperature An example of assigning the constant value 10 C can be seen in Figu
50. ed pipes directory InclinedCylinders code version 2 5 76 A pipe with thick wall 76 A pipe with thin wall 79 Results 82 Example with inclined hemisphere and inclined rectangular pipe directory InclinedSphere code version 2 5 83 Inclined hemisphere 83 Rectangular pipe 85 Results 88 Model reactor directory ModelReactor code version 2 5 89 Bibliography 92 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM 1 Authors and contributors Gef rdert durch The project underlying this report was funded by the fp Buderminiserun Federal Ministry of Economics and Technology Project iia Te number 1501369 aufgrund eines Beschlusses des Deutschen Bundestages Sub constractor Becker Technologies GmbH Becker 3 Technologies Project management GRS Gesellschaft fur Anlagen und Reaktorsicherheit A GRS mbH CoPool Simulation software Aivars Zemitis Oleg lliev Konrad Steiner Tatiana Gornak Sambit Jena Birte Schmidtmann CoPool Pre processor Aivars Zemitis Oleg Iliev Konrad Steiner Tatiana Gornak Shrinidhi Udupi Vidit Maheshwari Sandesh Hiremath CoPool Validation and testing Karsten Fischer Martin Freitag Becker Technologies GmbH Walter Klein Hessling Martin Sonnenkalb GRS mbH Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM 2 Overview In this document the usage of the software CoPool is described The software allows the simultaneous simulation of
51. element SpecialPointsWall Since the geometry can contain different wall objects different compounds it is necessary to define special points for each compound 17 2 1 Element SpecialPointsWall in Geometry xml Each compound has to contain the element WallGrid comprehending information about the wall discretization The element containing information about special points in a compound is named SpecialPointsWall This element should be a child element of WallGrid It is not required for a compound to contain the element SpecialPointsWall If during the reading process of the xml document a compound does not contain the element SpecialPointsWall for this compound no special points will be created and no special evaluation of the solution in this wall object will be done XML Notepad D SVN trunk CoPool examples SpheresWall Geometry xml io j File Edit View Insert Window Help De el 2 amp X a DASVN trunk CoPoolexamples SpheresWall Geometry xml v Tree View XSL Output Compounds WalliIsActive true CylinderCount 1 Cylinder coordSys cylindrical SuppPointsR 0 0 8 1 CellsR 10 1 SuppPointsT 0 6 2830 CellsT 20 SuppPointsZ 6 1 cellsz 30 comment start charact length CenterLine_P 00 1 Radius 0 8 Height 4 comment start charact length 4 SpecialPointsWall Name Cylinder MaterialType Copper InitialTemperature 50
52. ematik ITWM x XML Notepad D CoPool SubRooms SubDomainFusion xml o 8 s File Edit View Insert Window Help DEU 9 aa x Ai D CoPool SubRooms SubDomainFusion xml v Tree View XSL Output xml Oo version 1 0 encoding UTF 8 LinkLayer H D N 2 comment 4 numbers room color initial liquid JE ayeri O U H O RoomColor EEE 20e M NroomsConnected 2 H SubRoom1 3 6 20 30 l SubRoom2 4 6 20 20 i amp comment 4 numbers room color initial liquid GQ Layer2 RoomColor 6 0 20 20 NroomsConnected 2 SubRoomi 2 0 20 20 SubRoom2 5 0 20 20 Error List Dynamic Help Description File Line Column Saved Figure 20 Data stored in SubDomainFusion xml In this example the container includes 2 link layers Each link layer connects 2 sub rooms Each sub room i e also the link layer is described by 4 variables Sub room color Liquid height in meters trom the deepest point in the given sub room Air temperature in the sub room C Initial liquid temperature in the sub room C In the above example the existing sub room colors are 5 3 4 6 and 2 Since we have 5 sub room colors this means that we have 5 different sub rooms Attention Those numbers are generated by pre processor and must be changed by the user It is recommended to visualize the COPREP_OUTPUT Fluid vtk file using visit or paraview and to indentity the color of sub rooms Each time If pre proc
53. emember that the fluid mesh in this case Fluid vtk also contains an outer wall which has the color 110 The extracted outer wall can be seen in Figure 53 58 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM DB Fluid vtk Preudocdor or ompound 109 10 10 8 105 103 1100 Mere 115 0 Min 2 000 Mesh ar me Figure 53 Sliced outer boundary of the fluid mesh corresponding to color 110 15 2 Vtk files created by the pre processor for wall objects For each wall compound the pre processor creates a wall mesh in the corresponding coordinate system For visualizing the wall meshes the vtk files stored in the directory COPREP_OUTPUT can be employed The user should utilize these vtk Tiles Tor checking the correctness of colors of the internal voxels and also of the boundary voxels Beside this some wall objects can have overlapping parts It is necessary to check that these parts are correctly estimated 15 2 1 Boundary voxels corresponding to the neighboring fluid sub rooms Boundary compounds set limits for the different sub rooms It is important that each bounding wall knows at what part of the boundary what fluid sub room Is Its neighbor This is achieved in the following way the pre processor paints an additional layer of one voxel on the boundary of the wall object using for this layer the color of the corresponding neighboring fluid sub room The file WallColors xml see Figure 50 and F
54. er s task manager 1 CoPool Fraunhofer ITWM Open _Preproc _ simi Eat sto Ready Figure 5 Status message Ready after a pre processor or simulation step The pre processor can be stopped without obtaining the output Tiles by pushing the button Stop This button can be used if some unexpected behavior of the pre processor is observed In our example project directory the following content can be seen by now Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM Organize v Include in library v Share with v Burn New folder av Fil gt Favorites Name j Type Size W Desktop E _ COPREP_OUTPUT File folder m Downloads DataBase xml XML Document 3 KB Recent Places Geometry xml XML Document 17 KB SubDomainFusion xml XML Document 1 KB Libraries Documents R ae Figure 6 Content of the project directory after running the pre processor The content of the sub directory COPREP_OUTPUT depends on the generated geometry The main file groups are the following e txt Tiles containing step sizes for meshes e LeS files containing geometric information for each mesh e vtk files to visualize each mesh and test the correctness of the boundary zones e xmi files which are used for domain decomposition methods Additionally the file SubDomainFusion xml is created This file contains information about the existing sub rooms In this file the user can prescrib
55. es Geometry xml v Tree View XSL Output ConfigFlow General ConfigFor Flow 4 TakeWallsIntoAccount true DoSimulations true ResultsDirectory results 4 VoxelColors 4 GeomFile Fluid Les DataBaseFile DataBase xml MaterialName Water20 4 StepSizeFile Fluid stepsize txt FlowParam NumbofSinks 1 4 Sinkl Sink O ge eee Description File Line Column The XML element is not declared Geometry xml 2 Figure 32 TurbParameters as a new child element to FlowParam In this version the turbulent viscosity and the turbulent conductivity coefficients are included We will describe viscosity and heat conductivity separately 10 1 Turbulent viscosity Turbulent viscosity will be represented as a new child element TurbViscosity of the element TurbParameters TurbViscosity contains again two child elements Horizontal and Vertical Each of these elements should be represented as a table see section 5 In the example in Figure 33 we have set the horizontal turbulent viscosity to O kg m s The vertical turbulent viscosity is set to 10 kg m s This means that the actual viscosity in the horizontal direction will be equal to original value found in the data base The vertical viscosity used for simulations consists of the viscosity found in the data base increased by 10 kg m s 35 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM x AML Notepad D Examples
56. escribe the mesh and the geometry of different objects in an appropriate format These data are taken from the file Geometry xml by using the pre processor The installed example Cuboid is ready for use If this directory is selected then we can start the pre processor 2 Starting pre processor using the button Preproc The geometry description should be stored in the file Geometry xml as described in the pre processor s manual If this file is available in the chosen directory we can push the button Preproc It is important to see the status Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM message Running on the GUI If this is not the case some installation problem occurred CoPool ZA Fraunhofer ITWM Figure 4 Status message Running on the GUI The pre processor is generating all wall geometries corresponding meshes and also the corresponding fluid mesh This data is stored in a sub directory called COPREP_OUTPUT After a few minutes the status message Ready should appear The time required for the pre processor depends on the number of wall objects and the size of the grids Fine grids can cause the pre processor to run a long time This is because different searching operations are done in all meshes Fine grids can also require large computer memory Therefore Tor large simulation projects please follow the memory usage of CoPool using the comput
57. essor is running the SubDomainFusion xml is created again and the previous changes are lost It is recommended to save the changed SubDomainFusion xmll file with different name Later this file can be used for restoring the necessary values 21 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM Remark about the initial liquid temperature In the actual version of CoPool the initial liquid temperature plays an important role even when the initial liquid level is zero If we start to Till some sub room because we activated a source then automatically the minimal water deepness which is 1cm in the actual version is set in this sub room Therefore at the beginning of the filling there is a 1 cm liquid layer in the sub room having the initial temperature given in SubDomainFusion xml 7 1 1 Initial level of the liquid Pre processor automatically assigns the different sub room colors Also for all initial values some default values are written in the corresponding files The user should edit only these values For the liquid level the default value is O rooms are empty The height of the liquid is measured trom the deepest point in the sub room to the actual water level For a link layer the deepest point is where it touches the maximal water level of the lower sub rooms it connects There are a few more details about link layers which should be taken into account e For technical reasons if we prescribe the dee
58. ew XSL Output Error List Dynamic Help Description File Line Column Figure 9 XML Notepad This or another Xml editor can also be started separately The user edits the necessary files and then starts again the pre processor and the simulation program 5 Stopping the pre processor or the simulation using the button Stop The button Stop aborts the actual pre processor or simulation run immediately The software can be stopped for example if the user notices that some changes have to be made After the concerning data has been edited we can again run the pre processor or simulation software The user does not need to delete files created by the pre processor or the simulation code All result files are deleted automatically before starting simulations The pre processor overwrites files if they already exist 10 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM 5 Tables used in CoPool Tables are important parts of the input files There can be time based tables for some parameters as sinks or temperature based tables for temperature dependent material parameters In all cases the input format is the same therefore tables are explained without any special context By now CoPool allows several formats of tables This is because some primary formats are not excluded from the program The table consists on n argument values ti i 1 n and n function values fi i 1 n It is assu
59. file Fluid vtk and visualize the data using Pseudocolor Compound_100 then after clipping and applying a threshold for the variable Compound_100 it is possible to get information about different groups of voxels in Fluid vtk The file Fluid vtk should correspond to the file Fluid LeS which is used to construct the simulation mesh in the simulation software On the base of the example SphereWalls which is delivered with the software we will now show which information can be obtained from the fluid mesh 15 1 1 Sub rooms in fluid mesh The pre processor automatically classifies the sub rooms in a 3D geometry This classification gives intormation about the possible filling scenarios Separate sub rooms can be filled separately Sub rooms which connect other sub rooms are called link layers Information about sub room colors used in Fluid vtk Is stored in the file SubDomainFusion xml It is important to check before simulations that the room classification is done correctly In the example SpheresWalls the content of SubDomainFusion xml is shown In Figure 47 E X XML Notepad D Examples SpheresWalls SubDomainFusion xml o amp amp File Edit View Insert Window Help D a led 44x D Examples SpheresWalls SubDomainFusion xml v Tree View XSL Output xml version 1 0 encoding UTF 8 2 62 LinkLayer 4 N 1 comment 4 numbers room color initial liquid height in um Room
60. gure 27 X XML Notepad D Examples SpheresWalls Geometry xml o amp ss File Edit View Insert Window Help DEU 9 Pe x a amp amp 3 D Examples SpheresWalls Geometry xml ba Tree View XSL Output 3 Document A DataBaseFile DataBase xml B ConfigFlow 3 BoundFlow BoundaryPart B Inlet NumbSimpleCond 2 3 Eondi Se ere donee nats Aan eee amen Variable P 4 Btype 0 comment Value 0 Zero flux 1 Non zero flux 2 m e _ 0 4 m p Error List Dynamic Help Figure 27 Pressure condition on the free boundary 8 2 2 Condition on the walls Solid part On the walls the pressure condition should also be fixed In this case the normal derivative of the pressure function should be O This means that Btype 1 and Value 0 The corresponding fragment of xml file is shown in Figure 28 E x XML Notepad D Examples SpheresWalls Geometry xmi File Edit View Insert Window Help 3 BS id i amp Ea 2 Ao H 4 D Examples SpheresWalls Geometry xml Tree View XSL Output O BoundFlow A BoundaryPart Inlet G outlet GQ Solid NumbSimpleCond 2 J Eondi De Variable P a Btype 1 comment Value 0 Zero flux 1 Non zero flux 2 Value 0 4 pon W a Figure 28 Pressure condition on the walls 29 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM Sources and sinks Sources and si
61. hod DDiterations 53 15 Checking the output files of the pre processor 53 15 1 File Fluid vtk 54 15 1 1 Sub rooms in fluid mesh 55 15 1 2 Walls in fluid mesh 57 15 2 Vtk files created by the pre processor for wall objects 59 15 2 1 Boundary voxels corresponding to the neighboring fluid sub rooms 59 15 2 2 Overlapping parts of wall objects 61 16 Simulation results 63 16 1 Simulation results for the fluid part 64 16 1 1 16 1 2 16 2 17 17 1 17 1 1 171 2 17 2 17 2 1 17 2 2 17 3 18 18 1 18 2 18 3 19 20 20 1 20 1 1 20 1 2 20 1 3 20 2 20 2 1 20 2 2 20 2 3 20 3 21 Fraunhofer Institut f r Techno und Wirtschaftsmathematik ITWM Scalars related to the fluid flow 64 Velocity vector 66 Simulation results for wall parts 66 Monitoring points for data evaluation 67 Monitoring points for fluid 67 Element SpecialPointsFluid in Geometry xml 68 Preparing FileCoordAndTime 68 Monitoring points for walls 70 Element SpecialPointsWall in Geometry xml 70 Preparing the input file for monitoring points of a wall compound 71 Check the correctness of the special points 72 Special simulation regimes 73 Simulating the fluid flow without taking into account the walls 73 Simulating the heat conductivity in walls without flow simulation 74 Excluding individual objects from the heat simulation 75 Compatibility of old examples with new versions 75 Advanced examples 76 Example with rotated and shift
62. id Voxel Compounds CompoundCount 5 WallisActive true SphereCount 2 z B Sphere CuboidCount 1 Qo Cuboid Name LowerHemisphere MaterialType Copper InitialTemperatt 50 BcType 0 comment 0 value 1 isolation 4 heat exchange 4 WallGrid B Compound2 3 Compound3 O Compound4 B Compounds FE a n 4 Ww p rv Te tee FR E Error List Dynamic Help Figure 38 Setting BcType 0 for Compound 13 2 Different boundary conditions on different boundary parts During the pre processor step classification of possible sub rooms is done These sub room colors are used for coloring of boundary voxels for each wall object If the given wall compound has as neighbors different sub rooms then it is possible to define different boundary conditions for corresponding boundary parts In the case of cylindrical or spherical coordinates also a special color 300 is used It corresponds to the artificial holes which are used close to coordinate center or close to the pole position As default boundary conditions here the symmetry condition is used The user can if needed in these places to prescribe some other condition 42 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM i X XML Notepad F Koeln1011 examples Thai Geometry xml le amp ss File Edit View Insert Window Help JS Gx au a v Tree View XSL Output H CellsR 1 10 1 a H SuppPo
63. igure 51 contains amongst others the elements WallColor and ColorList The color list contains all colors that appear on the boundary of the wall object In the example shown in Figure 51 ColorList contains the colors 4 3 201 and 203 Values less than 100 correspond to sub room colors In this case the wall object is in contact to the sub rooms with colors 4 and 3 Colors between 201 and 299 indicate overlapping parts of the object with some other object For an overview we give the ColoLists of all wall objects found in the example SpheresWalls 59 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM e Wall1 RightCube 202 3 e Wall2 LeftCube 3 201 e Wall3 LowerHemisphere 4 3 2 e Wall4 UpperHemisphere 4 3 201 202 e Wall5 Cylinder 3 The object numbers in this list may differ from the ones in Geometry xml Therefore the objects should be recognized by the object name rather than by their number From a list like the one above we can get a rough impression about the positioning of each wall object Wall5 Cylinder for example has on its boundary only one fluid color and no overlap This indicates that the faces of this wall object are in contact with the fluid of the sub room with color 3 Just likeWall5 the boundary of Wall3 LowerHemisphere has only fluid colors on Its boundary If we visualize the file LowerHemisphere vtk and set the thre
64. il plots FH Parallel Coordinates gt 9 Poincare gt E Pseudocolor gt p Scatter gt Sinks FT Spreadsheet gt T Streamline gt mesh_quality gt BW Subset gt operators gt Tenso time_derivative gt BE Truecolor gt velocity_magnitude mi S Vector gt f Volume gt Figure 59 Accessing the scalar values stored in flow vtk using Visit In Figure 59 it is shown how to access the scalar parameters stored in the files flow vtk using Visit In Figure 60 the parameter Sinks has been chosen 64 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM Figure 60 Visualization of the scalar value Sinks for the fluid part Here the position of the sink is indicated by a red voxel Since it is on top of the fluid it can be seen even though the opacity is 100 In case the source or sink is positioned inside the fluid mesh the attributes of the option Pseudocolor should be changed Varying the parameter Opacity can help to get a better view of the sink position 65 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM 16 1 2 Velocity vector The results of the fluid part contain one single vector variable the velocity m sec Vectors can be visualized using a special visualization tool In the overview given in Figure 59 chose Vector instead of Pseudocolor An example of a velocity field can be seen in Figure 61 pe aH i al Figu
65. intsT 0 6 2830 CellstT 20 SuppPointsZ 0 1 0 5 1 5 2 H Cellsz 1 60 1 comment start charact length a CenterLine P 001 H Radius 0 065 Height 2 comment start charact length B BcSubRooms oO NConditions text 2 comment Room color condition type 0 value 1 isolation 4 heat exchange 3J WallBcSubroomi text 240 text 300 0 80 c MaterialType Stahl c InitialTemperature 80 4 Im Error List Dynamic Help Description File Line Column Figure 39 Setting different boundary conditions for a wall compound 13 3 Boundary conditions for the temperature on contact faces with liquid in the case BcType 4 13 3 1 Method for the calculation of the heat exchange coefficient If the wall boundary is below the liquid level then a simplified heat transfer correlation explained below is implemented in CoPool Here we describe the main principles used for modeling the heat transfer between the fluid and the heat conducting wall In Figure 40 the schematic view of a fluid mesh and a wall mesh is given 43 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM Figure 40 Schematic view on the fluid mesh and the wall mesh The dotted red line with the red cross indicates the location of the variable Twa of the temperature of the wall surface Remember that the wall boundary can be represented also in curvilinear coordinate systems Therefore the wall boundary can be approximated m
66. itions for the temperature in walls In the following sections we will explain how to provide for CoPool all initial conditions needed 7 1 Initial values for air and liquid temperature The pre processor does the room classification concerning the flooding see pre processor s manual This information yield what parts of the container can be flooded separately and which ones are connected The information about room classification is written in the file SubDomainFusion xml Each room has an appropriate number room color Sub rooms which connect two sub rooms are called link layer So far a link layer can only connect two sub rooms The link layer is considered as a normal sub room i e the initial liquid level and temperature should be prescribed for this sub room too Each sub room is associated with some color In Error Reference source not found an xample of five sub rooms can be seen Colors 2 3 4 5 and 6 correspond to different sub rooms Sub rooms with colors 5 and 6 are link layers because they are connecting separate sub rooms Color 4 Figure 19 An example with 5 sub rooms Colors 5 and 6 correspond to link layers because these sub rooms connect other separate sub rooms For the liquid level the default value is set to O rooms are empty In a typical SubDomainFusion xml file can be seen This file corresponds to the room classification given in Figure 19 20 Fraunhofer Institut fur Techno und Wirtschaftsmath
67. lColor xml o amp ss File Edit View Insert Window Help D ea 438 X A G amp amp D Examples SpheresWalls COPREP_OUTPUTWallColor xml v Tree View XSL Output 2 5 Walli a Wall2 Bl ee i ne Wall EEE EEE CoordSys 2 WallColor 112 MaterialType Copper O Name UpperHemisphere _ BoundaryColorCour 4 InitialTemparatu 50 ColorList 4 3 201 202 Walls 4 il p yi Figure 51 Color information about a wall compound Until now for us it is important to know that the wall color of this compound is 112 The voxels describing this wall should also be found in Fluid vtk Using 5 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM the option threshold in ParaView or Visit we can extract the wall colors from the fluid mesh The corresponding wall part can be seen in Figure 52 DB Fluid vtk Pseudocolor Var Compound_100 300 0 Figure 52 Wall part in fluid mesh corresponding to the UpperHemisphere in example SpheresWalls Similarly all other wall parts can be extracted from the fluid mesh It is important to see that each wall part exists in the fluid too By now real heat exchange between the liquid and walls can only happen if the concerned wall part is represented in the fluid mesh The heat conductivity in unresolved wall objects can be solved But the heat flux from such wall objects to the fluid cannot be taken into account recently It is important to r
68. lement IsFluid which should contain the value true if the material is a liquid and false if it is a solid Recently the code requires the following parameters for fluids e Dynamic viscosity kg m s e Density kg m e Heat capacity Co J kg K e Heat conductivity lambda W m K e Volume expansion used for the Boussinesg term 1 K e Reference temperature for the Boussinesg term C An example of water parameters can be seen in Figure 15 For the first four parameters the previously described tables see section 5 can be used The last two parameters are constants In the code additional non linear dependencies for air and liquid are implemented These are used to calculate the heat exchange coefficients The corresponding procedure is described in section 13 15 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM x XML Notepad D Examples SpheresWalls DataBase xml Ls Je ss File Edit View Insert Window Help DEN cA re amp DExamplesiCuboidiDatabase xml z Tree View KL lversion 1 0 encoding utf 8 z ER DO Materials J H Number fMaterials z Materialo W MaterialName Water20 H IsFluid true H E Density E E0 DynViscosity P Feomment kg m s eee Ey Cp uf Fcomment J kqg K DO lambda on comment gt 0 6 W m K H E VolumeExpansion i i comment 0 0002 1 K H A ReferenceTemperature 10 D Fomen
69. ll objects is switched off all other connected walls should also be switched off In case of nonobservance an error occurs 19 Compatibility of old examples with new versions In previous versions there were not as many information concerning walls in the file Geometry xml as there are now Running the newest version of the pre processor software with old examples that do not include all necessary information may lead to a crash Only if the files Fluid LeS and Fluid_stepsizes txt are available the simulation might be working correctly In this case we can try to run CoPool without running the pre processor beforehand To do so we have effect the following three steps 75 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM 1 Switch off the wall influence In earlier versions the element WalllsActive was not yet included so this element needs to be added in Geometry xml XML Filelnout Compound1 Set this value to false and repeat this procedure for all wall objects 2 Copy the files Fluid LeS and Fluid_stepsized txt to the sub directory COPREP_OUTPUT 3 Run the simulation code The simulation depends on the content of the xml input files The xml files can be edited with an xml editor When the xml files are prepared the code can be started Once the code is running there is no other possibility to intluence the run but to push the Stop button on the CoPool G
70. lor The projection will be done also to sub rooms below this one if needed e Assume that HasToBeMoved is set to true In this case the source moves trom its original position to the closest point of the corresponding free surface It means that horizontal and vertical shifting of the source will be done automatically 9 3 Prescribing intensities for sinks and sources Intensities of sinks and sources are prescribed using tables cf section 5 Currently all three formats can be used In Figure 29 an example with the third table format for source intensities can be seen 10 Turbulent parameters The recent CoPool version allows the user to change the viscosity of the liquid in the file Geometry xml without changing the value in the file DataBase xml There is the possibility to define different values for horizontal and vertical viscosity and or for horizontal and vertical heat conductivity Recently these parameters can only be constant values constant tables The defined values will be added to the original values from the data base To use turbulent parameters it is necessary to include in Geometry xml for the element FlowParam a new child Element TurbParameters see Figure 32 34 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM XML Notepad D SVN trunk CoPool examples Spheres Geometry xml DS File Edit View Insert Window Help D ae a yax a j DASVN itrunk CoPoolexamples Spher
71. matik ITWM A XML Notepad D SVN trunk CoPool tests AddTestExamples SphereCylConnected ex3 Geometry xml o X File Edit View Insert Window Help Deo 9 ya x a DASVN trunk CoPool tests AddTestExamples SphereCylConnected ex3 Geometry xml v Tree View XSL Output 4 FileInput a Document 2 amp ConfigFlow General TakeWallsIntoAccount true ConfigFor Flow DoSimulations false ResultsDirectory results HeightOfFreeBoundary 0 01 VoxelColors u GeomFile Fuld DSS jhk DataBaseFile ff DAt Base Me MaterialName Water20 StepSizeFile Fluid stepsize txt FlowParam SteppingParam 3 LinSolvParams LSTol i i DDIterations 3 BoundFlow a Errar list Dunamia Lalin Figure 46 Setting parameters for the linear solver and DD method Formally it would be possible to set different tolerances for each equation In this case for all equations the same tolerance is used Therefore we suggest not increasing this parameter 14 2 2 Iteration number in domain decomposition method DDiterations The parameter DDiterations is important for the domain decomposition DD method This method is used for solving the heat equations in walls In CoPool a version of overlapping DD method is implemented The parameter DDiterations tells how much iteration during one time step should be done The default value is 1 This value is set automatically if this parameter is not available i
72. means that the z axis is rotated in yz plane Because the original grid in built in soherical coordinate system and then transformed then the resulting discretized wall object is smooth 5 Figure 80 Inclined hemisphere represented on the wall grid 10 This wall object has relatively large wall thickness Therefore this wall is also fully resolved on the fluid mesh If we filter from the Fluid vtk cells with the color 111 then the following representation of the hemisphere can be obtained see Figure 81 84 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM Figure 81 Representation of the inclined hemisphere on the fluid grid 20 2 2 Rectangular pipe The second object is a rectangular inclined pipe which is obtained using Boolean conjunction between two cuboids The parameters are given in Figure 82 85 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM Compound2 WalllsActive true cuboidCount 2 Cuboid Cuboidi Origin 0 3 2 Coordone 4 0 0 CoordTwo 04 0 Height 4 comment lt CoordThree gt 0 0 16000 lt CoordThree gt Layers 1 GQ Cuboid2 Origin 1 2 2 Coordone 2 00 4 CoordTwo 02 0 Height 4 comment lt CoordThree gt 0 0 16000 lt CoordThree gt Layers 1 3J WallGrid CoordSys rectangular SuppPointsX 1 5 4 Cellsx 20 SuppPointsyY 4 2 Cellsy 20 SuppPointszZ 7 1 4 Cellsz 30
73. med that the argument values are sorted in increasing order Additionally two numbers are given Add and Scale Now the true value of the parameter f for some given argument value t Is calculated by finding the value L t using linear interpolation from the table If t lt t then L t f If tot then L t fn If t gt t and t lt t then LW fit at ai ti The final value of f t is obtained by the formula f t Scale L t Add The parameters Scale and Add are some scalar values that should always be defined for the table The values n fi and tican be written in the files DataBase xml or Geometry xml in different formats For tables there is not a special keyword table but the code is checking for the following three keywords e Value is a keyword for a constant value e Nis a keyword for the number of rows in the table e Pairs is a keyword for pairs ti fi In each case the code expects different input formats 11 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM Only one of the three keywords Is needed If for example the keyword Value is available and also the keyword N or Pairs then the keyword Value is not taken into account Table with one constant value If some parameter has only constant values then we can use the keyword Value This is the simplest table and it consists of only three elements Value Scale and Add X XML Notepad Co e js File Edit View Insert Window Help
74. ment CountSinksOfThisType Element Temperature 17 18 19 20 22 23 23 24 24 25 26 26 2 28 28 28 29 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM 9 2 Positioning of sinks and sources 33 9 3 Prescribing intensities for sinks and sources 34 10 Turbulent parameters 34 10 1 Turbulent viscosity 35 102 Turbulent heat conductivity for the liquid 36 11 Boundary conditions for the temperature of the liquid37 TEI Boundary conditions for the temperature on the free boundary 37 11 2 Boundary conditions for the temperature next to walls 38 12 AirParameters in Geometry xml 38 12 1 Structure of AirParameters 39 122 Structure of AirParameters for a given sub room 40 12 3 Time tables for the air temperature and the air velocities 40 13 Boundary conditions for the heat equation in walls 41 13 1 Setting the same boundary condition on the whole boundary41 13 2 Different boundary conditions on different boundary parts 42 133 Boundary conditions for the temperature on contact faces with liquid in the case BcType 4 43 13 3 1 Method for the calculation of the heat exchange coefficient43 13 3 2 Prerequisites for the calculation of a 47 13 4 Boundary conditions for the temperature on the contact faces with air in the case of BcType 4 50 14 Setting of simulation parameters 51 14 1 Element SteppingParam 51 14 2 Element LinSolvParams 52 14 2 1 Relative residuum LSTol 52 14 2 2 Iteration number in domain decomposition met
75. metry is mapped on to CoPool grids The number of cells is large and also the simulation time is long on PC 6 hours Here only few informations about this project are presented 20 10 l YofA X 10 gt t Figure 86 All wall compounds represented in corresponding coordinate systems In Figure 86 the complete wall geometry can be seen The fluid grid and the representation of the walls on fluid grid is shown in Figure 87 Figure 87 Fluid mesh and the representation of the walls on fluid grid The following problem is solved which should illustrate the termal stratification At the beginning all walls have the same temperature 60 C The liquid in outer 89 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM part Tills the room till appropriate level and the liquid temperature is 10 C The initial stage is shown in Figure 88 The blue color corresponds to the liquid Figure 88 Initial liquid level in outer part blue color Then in the middle part a liquid source starts to work with temperature 10 C and fills the middle part with liquid If the middle part is full then there is overflow to the next chamber At first stages the lower liquid part remains at the same level But there is direct contact between liquid and the lower part of the outer wall Therefore heat exchange at the lowest liquid portion can be observed from the beginning The liquid and wall temperature after 750 seconds
76. mpounds in the Geometry xml Tile The temperature in wall objects can only be simulated if for this compound a correct LeS Tile and a correct step size file have been generated 24 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM The initial temperature of a wall compound must be defined directly in Geometry xml For each compound there should be an element InitialTemperature where the initial temperature of the wall is specified In Figure 23 it can be seen how the initial temperature is defined for Compound In this case the initial temperature is set to 50 C F x XML Notepad D Examples SpheresWalls Geometry xml lo amp amp File Edit View Insert Window Help UB ao am x a amp amp Di Examples SpheresWalls Geometry xmi v Tree View XSL Output FileInput FluidGrid Voxel Compounds amp CompoundCount 5 B ES en i un WalllsActive true SphereCount 2 oO Sphere d CuboidCount 1 s EQ Cuboid Name LowerHemisphere c MaterialType Copper c InitialTemperature 50 WallGrid Compound2 Compound3 Error List Dynamic Help Description File Line Column Figure 23 Setting the initial temperature for Compund1 to 50 C Important remark In order to simulate the wall temperature and to take into account the initial temperature of the wall the element WalllsActive has to be set to true For the Compound1 the full path of
77. n Geometry xml In Figure 46 the parameter DDIterations is set to 3 The parameter DDIterations has a meaning only for wall objects with overlapping regions For wall objects which are fully separately iterations are not needed For these objects additional iterations are not applied and this is independently from the actual value of DDIterations 15 Checking the output files of the pre processor CoPool can solve complex hydrodynamic and heat problems But it can happen only if the geometry construction meshing setting initial and boundary conditions are done correctly Pre processor of CoPool is generating geometry 53 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM creating the discretization of this geometry and doing partitioning of boundary cells for setting boundary conditions Because a lot of work is done automatically it is important to check if all steps by the pre processor are done correctly The pre processor is preparing files in vtk format which can be visualized These files are written in COPREP_OUTPUT sub directory of the actual project directory Vtk Tiles are generated following the rules e For the fluid mesh only one vtk file with the name Fluid vtk is always generated e For each wall compound a separate vtk file is generated The name convention for these Tiles lt Compound name gt vtk In the following sub sections these files are discussed more in details 15 1 File Fluid vtk The
78. n as a boundary condition The air temperature for each sub room should be fixed in the file SubDomainFusion xml see section 7 1 2 50 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM 14 Setting of simulation parameters In this section the user will learn how to define parameters which influence the simulation process These parameters can be found in Geometry xml The first group of parameters belongs to the Element SteppingParam the second one to the Element LinSolvParams Element SteppingParam An example of parameter settings for this group can be seen in Figure 45 F X XML Notepad D SVN trunk CoPool examples Spheres Geometry xmi lo amp amp File Edit View Insert Window Help Lae 428 X 2 HE S DASVNitrunkiCoPoollexamples Spheres Geometry xml v Tree View XSL Output ConfigFlow 4 General ConfigFor Flow TakeWallsIntoAccount true DoSimulations true ResultsDirectory results VoxelColors GeomFile Fluid LeS DataBaseFile DataBase xml MaterialName Water20 StepSizeFile Fluid stepsize txt FlowParam E DImin sec 0 01 comment sec AdaptTimeStep false c DImax_sec 1 amp comment sec 4 CFLcoeff 0 8 c DToutput sec 10 H Tend sec 3000 MaximumStepCount 50000 2 Error List Dynamic Help Description File Line Column Figure 45 Parameters for managing the simulation process In this group the user can
79. nVariables 1 3 4 Variablel T Figure 67 Content of an element SpecialPointsWall In this case the information about coordinates of the monitoring points and the desired time moments have to be written in the text file specpCylinder txt This file has to be placed in the working directory i e in the same directory as Geometry xml The results for the special points will be written in the text file outCyl txt This file will be created in the working directory 17 2 2 Preparing the input file for monitoring points of a wall compound In the example shown in Figure 67 the name specpCylinder txt is used for the input file In general the name of the input file is not important as long as it has the same name as marked in SpecialPointsWall The structure of specpCylinder txt is exactly the same as for Tilecoordtime txt see 17 1 2 input Tile for special points of the fluid mesh Important remarks 71 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM e Even though each wall compound can be represented in different coordinate systems the coordinates of special points are always In Cartesian coordinates e Input files corresponding FileCoordAndTime must be different unique for each compound An example of the file specpCylinder txt can be seen in Figure 68 Home View O gt y t A 5 a s Ki f Find Courier New 11 A A E E it
80. nks are the key input parameters to trigger fluid flows in CoPool The user can define several sinks and sources In the fluid domain For the description of sinks and sources in CoPool only one type of element exists in the xml file It is called Sink If the intensity of a sink Is positive we will have a sink if the intensity is negative we have a source In the xml tile within the Element FlowParam there should be an Element called NumbOfSinks The corresponding value will tell the code how many sinks and sources will be used in the current run If this value is 1 then only the information about Sink1 will be used during simulations no matter how many sinks are described in the xml document In Figure 29 an example of a source can be seen We can see that it is a source and not a sink because the intensity is negative For sources the temperature must be defined Therefore the element TemperatureAvail is set to true X XML Notepad D Examples SpheresWalls Geometry xmi fo amp 3 File Edit View Insert Window Help E49 A aBx 3 9 D Examples SpheresWalls Geometry xml v Tree View XSL Output NumbOfSinks 1 Sink1 TemperatureAvail true HasToBeMoved true Temperature 10 cCountSinksOfThisType 1 SubRoomColor 3 Coordinates0 8 0 10 2 comment time table for sink instensity with N rows 4 Scale 1 F comment The value in the time table is scaled by Scale Add 0 Pairs 0 1
81. object not to the dimension of the wall surface element obtained by discretization Next CoPool calculates some material properties like A I thermal conductivity of water v m s kinematic viscosity of water and a m2 s thermal diffusivity of water These property functions are evaluated at Tmean the average temperature between fluid and wall Tmean Y2 Tiuia Twal We also need the thermal expansion coefficient 1 K of water which is obtained by differentiation of the temperature dependent density p T at constant pressure 1 Ap pAT In CoPool a table of material properties for water and air is implemented In this table the values for p A v P Cp at different temperatures can be found Virtually the data are independent of the pressure The data for B can also be used to calculate buoyancy forces in the equation of motion using the Boussinesq approximation The following parameters are important for further calculations Q is the thermal diffusivity is the Prandtl number The Grashof number relevant for natural convective heat transfer is calculated as Te 73 Gr Ao adi ia 13 1 46 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM where g 9 81 m s is the gravitational acceleration The Nusselt number for natural convective heat transfer under fully developed turbulent conditions is given by the correlation Nunat 0 135 Gr Pr 1 3 For forced convective heat
82. olean operations By now there is no tool given in the pre processor which automatically extracts the necessary information about the characteristic length L e Information for spherical objects For spherical objects only the radius of the sphere is needed It is necessary to write this value in the element WallGrid of the corresponding compound r X XML Notepad D Examples SpheresWalls Geometry xml le amp File Edit View Insert Window Help D pH 3 xa m D Examples SpheresWalls Geometry xml v Tree View XSL Output XML FileInput FluidGrid VoxelCompounds CompoundCount 5 EQ Compoundi WalllsActive true SphereCount 2 B Sphere CuboidCount 1 B Cuboid Name LowerHemisphere MaterialType Copper c InitialTemperature 50 3 WallGrid CoordSys spherical SuppPointsR 0 15 CellsR 70 SuppPointsT 0 3 13 3 14159 Cellist 40 10 SuppPointsP 0 6 2824 Error List Dynamic Help Figure 42 Setting the information about the characteristic length of a spherical object In the example seen in Figure 42 the radius used as characteristic length for the sphere is set to 15 m e Information for cylindrical objects Because In the general case the cylinder can have different inclinations the user has to provide more information for cylindrical objects e CenterLine_P gives the orientation vector of the cylinder e Radius gives the radius of the cylinder
83. ore exact in comparison to the corresponding boundary trom the liquid side The associated water temperature Tiuia IS calculated using a weighted average of the temperatures in the neighboring fluid cells which are indicated by black crosses For the weights the inverse distances of the black crosses to the red cross can be used In the recent version of the software the closest fluid voxel is taken and the temperature from this voxel is used aS Tyyia The heat flow Q normal to the wall surface element is indicated by the dashed red line It is calculated as follows Q aA Twau Triuia Q W is the heat flow A is the area of the wall surface element in m and a is the heat transfer coefficient in W m K The heat flow from the wall has to be the same as the heat flow to the neighboring fluid cells energy conservation We assume that each wall face is related to only one appropriate fluid cell It 44 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM means that the wall face has a heat exchange only with one fluid cell But it does not mean that one fluid cell has a heat exchange only with one wall cell One fluid cell can have interaction with several wall cells and even with several wall objects The sum of heat fluxes trough all related wall faces is used as a flux boundary condition for this boundary fluid cell In order to calculate the heat transfer coefficient a a number of other terms must be calculated First
84. p amp File Edit View Insert Window Help DEU 9 4 Ga x 8 1 D ASVNitrunk CoPoollexamples SpheresWall Geometry xml v Tree View XSL Output RoomColor 4 Temperature comment Time table for temperature Scale 1 4 Add 0 H Pairs 0 50 1000 100 comment Time tables for each velocity component vi LARI Scale 1 Add 0 Pairs 0 5 500 10 SubRoom2 Error List Dynamic Help Figure 37 Time tables for the temperature and the velocity component Vx in the sub room with color 4 In this example the air temperature in the sub room with color 4 is growing linearly starting from 50 C at t 0 seconds until it reaches 100 C at 1000 40 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM seconds Once t 1000 s is reached the temperature remains constant 100 C e The air velocity component Vx is also linearly growing starting from 5 m s at t 0 seconds and achieving 10 m s at t 500 s After having reached 10 m s at 500 seconds the velocity remains constant at 10 m s 13 Boundary conditions for the heat equation in walls It is necessary to detine boundary conditions for each wall compound separately There are two different ways for defining the boundary conditions e Define the same boundary condition for the whole boundary of the given compound e Define different boundary conditions on different parts of the boundary for the given wall compound
85. pness of a link layer it corresponds only to the part above the two sub rooms this link layer connects The deepness is measured in the sub room with appropriate color e lf the link layer has non zero deepness then the user should explicitly fill the sub rooms below In this case it is not necessary to know the exact deepness of those sub rooms It is sufficient to give some deepness that is larger than the real deepness of the sub room 22 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM e An important restriction until now each link layer can only connect two sub rooms If Pre processor generates link layers which connect more than two sub rooms the resulting SubDomainFusion xml file is not usable for simulations with CoPool now see Figure 21 on the left Figure 21 On the left the link layer sub room 4 connects 3 sub rooms 1 2 and 3 On the right two link layers can be seen The link layer 5 connects sub room 1 and sub room 4 The link layer 4 connects sub room 3 and sub room 4 e In this case it is necessary to change the geometry One has to generate a small link layer in between the connected rooms see Figure 21 on the right This sub room configuration is allowed in CoPool 7 1 2 Air temperature Each sub room also link layers can have different air temperatures The air temperature only has a meaning if the room is not filled with liquid The given air temperature can be taken into account for the
86. r Institut fur Techno und Wirtschaftsmathematik ITWM Before starting the installation of CoPool please uninstall any previous version of CoPool if existing CoPool defines particular environmental variables therefore two different versions of the software at the same time are not advised Attention Install the code as a normal user and not as administrator During the installation the administrator s password will be required but if the code is installed from the administrator s account only the administrator can run the program even if the flag Everyone is set during the installation 3 1 Installation resources The software CoPool is using several open source tools which are important either to prepare input data or for the visualization of data Some of them are e Paraview 3 10 0 http www paraview org e Visit 2 2 1 httos wci linl gov codes visit download htm e Notepad http www chip de downloads Microsoft XML Notepad 2007 v2 5_12993437 html The first two tools can be used for the visualization of constructed geometric objects and for viewing the simulation results The third tool can be used to edit xml tiles As described in the pre processor s manual xml files are the main input for CoPool For using XML Notepad 2007 directly trom the GUI it is necessary to install this tool to the standard place on your computer C Program Files x86 XML Notepad 2007 The other two programs Paraview and Visit
87. re 26 conditions for the velocity components on the free boundary can be seen The interpretation of these conditions is the following Due to the fact that in CoPool the Inlet corresponds to the tree boundary the conditions on the Inlet part can only be used on the top surface of the fluid voxel In the code the top surface face of the fluid voxel is called vfTop On the free surface we set the normal derivatives of the horizontal velocity components to 0 This is achieved by setting the boundary type Element Btype to 1 zero flux 2 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM For the vertical velocity components the boundary type is set to 0 This means that the velocity component will be directly assigned In the xml file the value for Vz is set to 0 In the code this value is changed in correspondence to the mass balance in the actual sub room x XML Notepad D Examples SpheresWalls Geometry xmi ERTEM TES File Edit View Inset Window Help d Gg i2 amp a ed A D Examples SpheresWalls Geometry xml v Tree View XSL Output FaceGroupil tcomment For this group zero values are prescribed VelCondSin true comment In this case velocity values are prescribed NumberOfFe 1i Facel viTop EQ Vx Btype 1 comme Value 0 Zero flux 1 Non zero flux 2 Value 0 Ba Vy H Btype 1 comme Value 0 Zero flux 1 Non zero flux 2 Value 0 3 Vz
88. re 30 Tree View XSL Output StepSizeFile ET Fe 0 nn nn nn nn nun FlowParam PEE E ee Numbofsinks 1 B Sink1 TemperatureAvail true HasToBeMoved true Temperature 10 Hl cee p 1 Y Figure 30 Assigning a constant temperature value 10 C to the Sink1 In more general case the temperature is time dependent Therefore also time tables for the temperature of sources are allowed An example is shown in Figure 31 XML Notepad D SVN trunk CoPool examples SpheresWall Geometry xml EG S File Edit View Insert Window Help DEN yarnr x Biel BAO eee EEA ice Neola v Tree View XSL Output 3 Sinkl TemperatureAvail true HasToBeMoved CUS nn Temperature ee ee ee ee eee Pairs 0 10 50 20 100 30 150 40 200 100 300 10 CountSinksofThisType 1 H O SubRoomColor ill r 8 0 10 2 Figure 31 Temperature of the source as a time table 32 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM The temperature Is defined as a time table using Pairs In the pair the first value corresponds to the time and the second value to the temperature The corresponding table is shown below see Table 1 Table 1 Time table for the source temperature corresponding to Figure 31 VE DEE In this case all 3 formats for a time table described in section 5 can be used 9 2 Positioning of sinks and sources The positioning of sinks in 3D structures is a difficult
89. re 61 Velocity field in a complex geometry 16 2 Simulation results for wall parts Each wall part has its own result files for the temperature The result Tile s name consists of the compound name and the time loop index at which the result is written In the example SpheresWalls the results for the wall parts are stored in files named Cylinder vtk LeftCube vtk LowerHemisphere vtk RightCube vtk and UpperHemisphere vtk The wall meshes can be created in one of the following coordinate systems e Cartesian coordinate system e Cylindrical coordinate system e Spherical coordinate system 66 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM In Figure 62 an example of results showing the temperature distribution at some time moment can be seen in Cartesian cylindrical and spherical coordinate systems ELE Die p BS 53 E EE ON 5 gt cf SE ii 5 Bs ee E Figure 62 Examples for temperature results in wall parts using Cartesian cylindrical and spherical coordinate systems 17 Monitoring points for data evaluation The visualization of the results gives an overview of the solution at different time moments Normally the visualization tools contain additional possibilities to analyze the solution Here we do not want to discuss these possibilities but show an option to get additional information using CoPool Using the option special points CoPool is able to create an additional text file
90. s regime can be simulated if the following settings are used e TakeWallsintoAccount true e DoSimulations false 14 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM rm X XML Notepad D Examples SpheresWalls Geometry xml o amp es File Edit View Insert Window Help DEU 9 anx D Examples SpheresWalls Geometry xml v Tree View XSL Output CompoundCount z A Compoundi Compound2 Compound3 Compound4 Compounds Document DataBaseFile DataBase xml 5 ConfigFlow gussnnmnnnunnusuuuneeee LLLLLL22222222222222222 Ifpeonensensnnnunnnensunnnnnsunnnnnnensnnnnunsnnnsnnnnnnnennunnnunnnnnnunnnnnnnnunnnnnsnnnnunnnnnsnnnnnnnennansnnnnnonnennnnnseonunnnunnnnnnensnnnnennnnssnnnnnsnunsnnnnansnnnsnennnnsnnes errr i Se amp ConfigFor Flow TakeWallsIntoAccount true DoSimulations false 4 m results Figure 71 Settings to calculate only the heat in walls 18 3 Excluding individual objects from the heat simulation It is possible to run the code for the fluid part and the wall parts excluding only some specific walls from the simulation In this case the following setting has to be used e TakeWallsintoAccount true e DoSimulations true Additionally choose the wall compound that will be excluded and set its parameter WalllsActive to false Remark It is necessary to take care in case there are overlapping wall objects If one of the overlapping wa
91. section 12 11 2 Boundary conditions for the temperature next to walls Boundary conditions for the temperature of the liquid which is in contact with walls are set fully automatically The boundary face of a fluid region might be in contact to several boundary faces of wall objects These relationships are calculated automatically Recently it is assumed that one face of a wall voxel has a relationship to only one fluid region face As a boundary condition for the fluid face the heat flux condition is used For the given fluid face on the boundary the sum of all wall heat fluxes related to this fluid face is evaluated This flux is then used as a boundary condition In section 13 more details on the boundary conditions of the wall side are given 12 AirParameters in Geometry xml In CoPool the user has several possibilities to define air conditions in sub rooms This can be done in two ways The simplest case is to define a constant air temperature in the sub rooms For this purpose the file SubDomainFusion xml is suitable see section 7 1 2 By now It is possible to give more detailed information about the air flow This can be done by adjusting the element AirParameters in Geometry xml Remember that the pre processor estimates how many sub rooms are available in the constructed geometry and automatically creates the file SubDomainFusion xml For each sub room a default value for the air temperature is prescribed The user can edit
92. shold between 2 and 4 from the list we see that we are interested in the colors 2 3 and 4 then we can see the boundary voxel colors of this wall object Figure 54 Boundary voxels corresponding to different fluid sub rooms blue sub room 3 green sub room 2 and red sub room 4 If we apply the clipping operator we can see that the shown colors are given only on the boundary layer 60 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM Figure 55 Result of the clipping operator applied to the object from Figure 54 The colors seen in Figure 54 and Figure 55 show that there is no contact to other wall objects or other fluids Important remark It is very Important that the boundary of the wall objects contains colors that are different from the internal color If it is not the case the simulation code for the corresponding wall part breaks down If such problems appear it is necessary to check the parameters of the wall geometry and also the corresponding grid parameters If this does not help a transitional solution for this case is to set WalllsActive to false for the corresponding compound in Geometry xml remember that the compound index may differ from the wall index in the above mentioned list 15 2 2 Overlapping parts of wall objects In the discussed example the boundary of the wall objects Wall1 RightCube Wall2 LeftCube and Wall4 UpperHemisphere contain not only
93. sts of 6 wall objects Here we present the results concerning the two inclined cylinders The problem what Is solved is the following At the beginning all wall objects have the fixed temperature 60 C Then a source with the temperature 10 C is switched on All walls have very good heat conductivity copper Therefore intensive heat exchange between walls and liquid can be observed The walls becomes cooler and the liquid becomes warmer o 2 1 Cycle 202 Tme 1150 Va 22 1708 15 13 1001 DO Small yInder300 vik Cycle Ime 1500 vanT 000 50 00 Do 20 20 00 K Be n 20 V Do B a v i 5 Smeal ince 300 vtk 12 00 0 Time 1s00 meh Z ur n a y Figure 78 Temperature distribution in the large and the small pipe Additionally the actual liquid level can be seen In Figure 78 the temperature distribution in pipe objects and the liquid level after 1500 seconds can be seen 82 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM 20 2 Example with inclined hemisphere and inclined rectangular pipe directory InclinedSphere code version 2 5 The example InclinedSphere is showing that the wall transformation is working also in the case of spherical and rechtangular walls In the example there are two compounds available 20 2 1 Inclined hemisphere The compound with number 1 is an inclined hemishere The corresponding parameters can be seen in Figure 79
94. t ice Figure 15 Structure of water properties in the data base In the case of walls only three parameters are required so far e Density kg m e Heat capacity Co J kg K e Heat conductivity lambda W m k These three parameters can be detined as temperature dependent tables using any of the three formats for tables see section 5 x XML Notepad D Examples SpheresWalls DataBase xml fo E File Edit View Insert Window Help DEU aa x 3 E a DikkamplesiluboidiDataBase xmi X Tree View XSL Output O xml version 1 0 encoding utf 8 Materials y H NumberOfMaterials 5 B Materialo H Q Materiall S amp Hateriai2 Ce MaterialName Concrete H O IsFluid false H Density z comment kg m3 Cp comment J kg K lambda comment W m K ContactHeatTransfCoeff o H A Material3 3 GE Materials m Figure 16 Structure of material parameters for a solid 16 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM The structure of the material parameters for a solid material can be seen in Figure 16 Here also the keyword ContactHeatTranstCoeft can be seen This parameter is not used for simulations anymore The contact heat transfer coefficient is calculated using information about the characteristic length of the wall object liquid velocities and the temperature This topic is described in section 13 2 6 2 Remarks about input values e All input p
95. t part of the boundary Therefore only the Inlet and the Solid boundary conditions are used The Outlet s part is available in Geometry xml but must be empty The Inlet boundary part corresponds to the free boundary and the Solid boundary part to the contact zone between the liquid and the wall parts Until now for the pressure and the velocity on all wall parts the same conditions will be applied automatically or by user input 8 1 Boundary conditions for velocity 8 1 1 Notation for faces Each voxel has 6 faces In the code each face has an appropriate name These names are used if special boundary conditions should be applied on voxel 26 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM boundaries oriented in some prescribed directions Remember that the fluid mesh is a Cartesian mesh and the faces are oriented in coordinate directions The names for voxel faces are the following e For X direction vfEast in the positive and vfWest in the negative direction e For Y direction vfNorth in the positive and vfSouth in the negative direction e For Z direction vfTop in the positive and vfBottom in the negative direction All faces of a voxel can be seen in Figure 25 vfWest vfSouth Y X y vfBottom vfEast Figure 25 Names of faces of a fluid voxel 8 1 2 Conditions on the free boundary Inlet part We do not recommend changing these conditions In Figu
96. the fluid flow and the heat transport in complex 3D containers The user should be able to construct the necessary geometries using the pre processor software CoPrep For the usage of this software see the pre processor s manual In this document we assume that the user is familiar with the methods allowing the construction of the 3D meshes The used mathematical models are described apart In the CoPool user s manual we explain how to install the software how to manage the initial and boundary conditions and how to run the code and obtain the necessary results We would like to thank Karsten Fischer trom Becker Technologies GmbH Eschborn for the proposed models for the calculation of the heat exchange coefficient section 13 3 1 and Martin Freitag from the same institution for suggested improvements of the text New features of the CoPool version 2 5 0 In this version an important feature has been added to the software CoPool The user can shift and rotate the wall objects see section 20 1 Attention This feature is under development and there is no guarantee that the code is working in all cases If this feature is used then it is necessary to check carefully the colors of the wall boundaries section 15 2 3 Installation The software is usually delivered as a package called CoPoolSetup msi which can be installed using the Windows Installer To date the installation is tested only for Windows 7 Enterprise x64 Fraunhofe
97. these default values in SubDomainFusion xml if needed 38 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM If it Is not sufficient to have only constant air temperatures for the sub rooms It is necessary to include the new element AirParameters in the file Geometry xml In recent versions there are the following rules concerning the air parameters e lf there is no element AirParameters in Geometry xml then the code obtains information about the constant air temperature from the file SubDomainFusion xml e lf the element AirParameters is available in the Geometry xml the information about air temperatures found in SubDomainFusion xml is not taken into account e If the user decides to include the element AirParameters in Geometry xml then the intormation about air temperatures should be given for each sub room recognized in SubDomainFusion xml 12 1 Structure of AirParameters The structure of this element will be explained on the basis of the following example see Figure 36 rm x XML Notepad D SVN trunk CoPool examples SpheresWall Geometry xml o amp File Edit View Insert Window Help EL am x a 3 D SVNitrunk CoPool examples SpheresWall Geometry xml v Tree View XSL Output xml version 1 0 encoding utf 8 amp comment Can be copy pasted G XML FileInput Document goeeecceccscossssccccccccescscsccsccccsecesesssssseseog c N subrooms 3 O SubRoomi O SubRoom2
98. this element is Filelnput VoxelCompounds Compound1 WalllsActive 8 Boundary conditions for the flow variables Since CoPool is solving the 3D Navier Stokes equations all flow variables the velocity components Vx Vy Vz and the pressure p need appropriate boundary conditions One part of these boundary conditions is set automatically and cannot be changed by the user The other part of these boundary conditions 25 Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM can be changed by the user We recommend to do it only for experienced users The boundary conditions for the liquid flow are described in Geometry xml under XML Document BoundFlow Historically the boundary of the fluid mesh was separated in three parts Inlet Outlet and Solid We can find these parts in the example file Geometry xml E x XML Notepad D Examples SpheresWalls Geometry xmi olla ls File Edit View Insert Window Help DEU am x a 9 D Examples SpheresWalls Geometry xml v Tree View XSL Output xml Can be copy pasted comment 3 XML FileInput Document DataBase xml DataBaseFile ConfigFlow BoundFlow B BoundaryPart Inlet m GD Solid NumberOfWallParts Error List Dynamic Help Description File Line Column Figure 24 Description of flow boundary conditions in Geometry xml So far pre processor does not provide a possibility for detining the Outle
99. w from the user s point of view Is taken into account in the simple graphical user interface of CoPool Below the workflow is explained more in detail The code itself is managed from a simple GUI which appears after clicking on the shortcut of CoPool Fraunhofer Institut fur Techno und Wirtschaftsmathematik ITWM CoPool FA Fraunhofer ITWM 7779 Figure 1 Graphical User Interface of CoPool All simulations using CoPool should be organized as separate projects Each project should be stored in a separate directory 1 Open project directory using the button Open By using the button Open the user fixes the actual simulation directory After clicking on Open a standard window appears which allows choosing the directory with the necessary input data For the first tests it is recommended to use the example projects that have been created during the installation process on the user s Desktop Existing examples are Cuboid Sphere Cylinder Wall Pool and CylindricalPool Assume we have copied the project directory Cuboid from the Desktop to D Examples Cuboid Then we can select this directory for simulations i Open Directory x 2 m gt Computer Data D Examples v Search Examples Organize New folder v Documents FE Name Date modified Type Size Music ad v di Cuboid 24 09 2011 07 53 File folder t Pictures Videos od Homegroup ME Computer amp

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