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VI-Suite v0.3 Manual - University of Brighton Faculty of Arts

1. O Upon opening a Blender file which already has a connected VI Chart node in the node editor a connec tion has to be redrawn to re initialise the node sockets O When conducting a sun path study after an animated LiVi analysis that uses an animated Hosek Wilkie sky background the animation key frames have to be removed manually from the sky background Oo Saving a png file from the matplotlib window on Windows will cause Blender to crash O Changing the legend scale type with point visualisation turned on can take a very long time for dense sensor meshes Dr Ryan Southall 33 School of Art Design Media VI Suite v0 3 7 Acknowledgements 7 Acknowledgements O O Thanks go to the Blender Foundation for the creation distribution and constant improvement of Blender Thanks go to the National Renewable Energy Laboratory for the multi platform compilation and distri bution of the Radiance binaries Thanks also go to National Renewable Energy Laboratory for the creation and distribution of the En ergyPlus software Thanks go to the Matplotlib Development Team for Matpltlib Copyright c 2012 2013 Matplotlib De velopment Team All Rights Reserved Thanks to Continuum Analytics for producing Anaconda which provides certain Python components for OS X and Windows platforms This product includes Radiance software http radsite lbl gov developed by the Lawrence Berkeley National Laboratory http www lbl
2. 5 4 4 Photon Mapping Photon mapping capabilities have been included in version 5 0 of Radiance Photon mapping can produce more accurate and quicker results in situations where light sources are to hard to find from the point of view of the LiVi sensor points e g light to the sensors is delivered through light redirecting devices and when there are specular surfaces that result in caustics A classic caustics context is the characteristic pattern at the centre of a obliquely illuminated reflective ring figure 36 Within the Blender interface there is one option relevant to using Photon mapping which is situated in Blender s material panel in the VI Suite Material tab This option turns on Photon Port status for that material As the Photon Mapping pre pass sends out rays from the light sources it is useful in some cases to turn on photon ports to guide these rays to the relevant geometry When for example doing a lighting analysis for the interior of a building setting up the Photon Port material for the windows on the building periphery will guide the lighting from the sky to the building interior vastly reducing up time it takes for the relevant scene geometry to receive the number of photons required The normal of the surface with the Photon Port material attached should point into the room in this case The node options relevant to Photon Mapping reside within the LiVi Simulation node Here Photon Map ping can be activated and the number
3. This optional node sets the reference temperature pressure and humidity for any ventilation cracks specified within the network If not created EnVi will assume standard values for these parameters which are the same as the default values presented within the node Dr Ryan Southall 22 School of Art Design amp Media VI Suite v0 3 5 Using the VI Suite 5 Using the VI Suite 5 1 Sun Path Projection Projecting a sun path analysis into the Blender scene requires a VI Location node to be created to provide the latitude and longitude co ordinates of the scene The VI Location node can either take L the latitude and longitude values from an EPW Pee Create Sun Path file or they can be entered manually The start oe and end month options of the location node are not exposed when doing a sun path analysis as a whole year is always considered Once the loca Figure 28 Sun Path node set up tion node has been set up a Sun Path node can be created and the Location out socket of the location node dragged to the Location in socket of the Sun Path node A typical node set up is shown in figure 28 The Sun Path node itself has no options only a button to be clicked to create the sun path Along with a sun path mesh a sun lamp and spherical mesh to represent the sun and a sphere Y Vi Suite is created to represent the sky The sun path has 4 materials as sociated with and the colour of each of these materials can be changed as
4. be a party or internal wall or a ceiling floor combination The second tells EnVi that the surface is a point at which air can enter or leave the space The last can be used for surfaces in the zone that do not transfer heat but do provide thermal mass that moderates the temperature of the zone The first two options become important for the EnVi network creation stage detailed in section 5 5 5 5 5 2 EnVi geometry conversion Once a Blender object which has been designated as an EnVi thermal zone or shading construction has been fully defined and materials applied where appropriate the geometry can be stripped down to only that geo metry required by EnergyPlus for simulation EnergyPlus like many whole house energy modelling systems only require geometry comprising of simple planes with construction attributes then associated with them An EnVi Geometry conversion is first required to turn complex Blender geometry into simplified geometry suit able for energy analysis During the conversion process Blender geometry on Blender layer 1 is converted to simplified Blender geometry on layer 2 Only the geometry specified as an EnVi zone and object faces with an EnVi construction material assigned are converted Every export will overwrite the geometry on layer 2 so itis important that any changes to form or materiality are made to layer 1 geometry and the EnVi geometry re converted with the EnVi Geometry node Upon export objects with an EnVi pro
5. weekdays weekends would for example set two day types for the next Untils option o Untils sets the schedule values with space separated end hour value pairs comma separated for each period within a day type and semi colon separated for each day type 12 00 1 24 00 0 24 00 1 would for example mean on the first day type weekdays the schedule value is 1 from midnight up to midday and 0 up to midnight and for the second day type weekends the schedule value is 1 up to midnight A whole day period must be covered so 24 00 should always be the last time specified If the first end day is less than 365 the three options above are repeated for the next year period Up to four year periods can be set 4 7 9 The EnVi Surface Flow node The EnVi Surface flow node creates a flow component within a solid building construction such as a wall floor or roof It con tains two input sockets Node 1 and Node 2 and two output sockets Node 1 and Node 2 Having sockets on both sides of the node makes node connections within the node tree more flexible but only one needs to be connected so if a node socket on one side of the node is connected the similarly named socket on the other side of the node will disappear All of these sockets are for connection to the surface flow sockets of EnVi Zone nodes If both Node 1 socket and Node 2 sockets are connected to two different EnVi zones the surface flow node is assumed to specify a flo
6. 3D Display If selected before the display button is pressed the results can be extruded to provide 3D result visualisation o Shadow Display button When clicked will initiate display and expose further display options o Only Render Removes some interface elements from the 3D view o Legend Turns on the legend display in the top left of the 3D view o 3D Level If VI3D Display was selected this number will extrude the results plane for 3D results visualisa tion In the Point Visualisation section 5 Using the VI Suite Y V 3D display Shadow Display Y Legend 3D Level 30 70 Point visualisation Enable Selected only Visible only Font size Font colour Font shadow Figure 33 Shadow study display options o Enable Turns on per point numerical visualisation of the results o Selected only Only the currently selected object will display numerical results o Visible only Only points not obscured in the 3D view show numerical results o Font size font colour font shadow changes the colour and size of the point numerics Figure 34 shows a shadow study analysis of the terrain around Mount Snowdon Figure 34 Shadow study analysis of Mount Snowdon Dr Ryan Southall 25 School of Art Design amp Media VI Suite v0 3 5 Using the VI Suite 5 4 LiVi Lighting Analysis Lighting analysis is conducted with the LiVi component of the VI Suite which acts as a pre post processor for the R
7. Southall 30 School of Art Design amp Media VI Suite v0 3 5 Using the VI Suite 5 5 EnVi Energy Analysis The EnVi component ofthe VI Suite is a pre post processor for the EnergyPlus simulation engine http apps1l eere energy gov An EnVi analysis requires a VI Location node to provide an EnergyPlus weather file for the simulation an EnVi Geometry node to pre process the full Blender geometry into the sub set of the geometry that will be used in the EnergyPlus simulation an EnVi Export node to convert the sub set of the Blender geometry and the building context to the EnergyPlus text format and finally an EnVi Simulation node to run the simulation Optionally a VI Suite chart node can be used to plot out the simulation results A typical node layout is Shown in figure 40 Figure 40 Typical EnVi node set up 5 5 1 EnVi construction specification EnergyPlus like many whole house energy modelling systems only requires geometry comprising of simple planes with construction attributes then associated with them These construction attributes are created in Blender using Blender s materials system Within Blender s Material properties panel is a section called VI Suite Material and within this section is the EnVi Construction Type drop down menu In this menu the basic type of EnVi construction can be specified o Wall Typical external and party wall constructions o Window Typical glazing constructions o Floor Typica
8. a VI Location node and results data from an EnVi Simulation or EnVi Results file node Up to three data sets can be plotted on the y axis via a iu dynamic number of input sockets that get created as cw 7 MN ere sockets are connected Ses Initially only the X axis socket is exposed Once this socket is connected a Y axis 1 socket is ex Figure 10 VI Chart node posed Once this socket is connected a Y axis 2 socket is exposed which should again be connected to the same Results out socket In total three Y axis sockets can be exposed All sockets should be connected to the same Location out or Results out socket Next to each connected socket menu items will appear to select the type of data to plot on the axis This contents of these menu items depends on the contents of the results embedded in the connected results node A Create plot button in the middle of the node creates the Matplotlib plot in a new window Buttons within this new window allow some manipulation of the chart and export to image file On Windows PNG export will crash Blender Select PDF or SVG export instead The options presented by the node are Create plot Climate Direct Solar W m o Day start and end day of the period to be plotted Defaults to the total day range of the results connected to the sockets Dr Ryan Southall 10 School of Art Design amp Media VI Suite v0 3 4 The Vi Suite Interface o Hour start and end hour of the da
9. desired or made transparent Once a sun path has been created a number of options are Sunpath scale presented with the 3D view properties panel in the VI Suite Display tab section 4 2 The sun path options display options available are shown in figure 29 The first and second options control the day of year and time of day for the position of the Font colour sun lamp and the sun mesh the third option controls the scale or size of the sun path any scaling done within the 3D view will reset upon changing the position of the sun with the first two options The fourth option controls the display of the hour numbers on the sun path If the Display hours option is selected then the last options control the represent ation of the hour numbers font size font colour and font shadow colour The sun path mesh can be moved around the scene and the sun will follow when the time of day year is updated Day of year and time of day can be animated within Blender and the sun will move accordingly If using the Cycles rendering engine a couple more capabilities are enabled If the Hosek Wilkie sky is selec ted as the sky texture in the world background settings the sun orientation within the sky texture will update to correspond to the sun path sun position In addition if the sun and sun mesh are given an emissive material with a black body temperature colour the black body colour will also change according to the position of the sun in the sky orange
10. export Blender information to a format that can be used for analysis O Analysis nodes that run analyses O Generative nodes that specify targets and geometry manipulation for Generative Design O Display nodes that display the results of analyses o Edit nodes that can manipulate data Some of these nodes are common to multiple types of analyses Manual Latitude 52 00 alculate Longitude 0 00 gelet aJ View Select Add Node Figure 3 Blender node editor Before any nodes are created the Blender file should be saved The VI Suite project directory will then be created in the same location as the Blender file is saved to with the same name as the Blender file name Within the node editor VI Suite nodes can be connected together to perform analyses Once the node editor has been selected for an interface area at the bottom of the node editor area will be a row of menu items and a row of icons figure 4 The main VI Suite node tree window is selected by selecting the sun icon in the icon row Once the sun icon has been clicked press the new button on the right to create a new VI Suite node tree The Add menu entry allows the creation of nodes within the chosen created node tree It should be noted that when switching between different node trees with the node tree icons the active node tree in any node tree window will be forgotten and must be selected again with the drop down menu to the left of the New node tree bu
11. import node The operator button converts the ASC file into Blender co ordinates and creates a mesh within the scene which accurately represents the ground heights in the ASC file Once this geometry has been imported it can be subject to further analysis for example a shadow study section 4 4 3 A render of the terrain around Mount Snowdon in Wales is shown in figure 8 Dr Ryan Southall 9 School of Art Design amp Media VI Suite v0 3 4 The Vi Suite Interface Figure 8 Render of ASC imported terrain height around Mount Snowdon 4 3 3 The EnVi Results File node The EnVi Results File node figure 9 allows for the load ing of a previously generated results file from an EnVi sim ulation for plotting The node contains a file select button which opens up a file selection window to navigate to the de sired file a text box that shows the file name and path of the currently selected file and a Process File button to con Select file vert the results file into data stored within the node Once the Process File button has been pressed the Results out socket should become visible for connection to a VI chart node Figure 9 EnVi Results File node Process file 4 3 4 The VI Chart node The VI Chart node figure 10 uses Matplotlib http matplotlib org to provide simple line plotting for certain types of data As of version 0 3 this chart Start _ 180 node can plot climate data from an EPW file selected within
12. of the occupants and the average air velocity within the zone all required for thermal comfort calculations and whether to calculate air quality via CO levels within the zone An occupancy node has the following options o Type specifies the occupancy type and the maximum value of this occupancy type to be seen by the zone o Maxlevel specifies the maximum level of the occupancy type o Activity level if no activity schedule is specified then a constant level of activity is specified here o Comfort calc turns on reporting of comfort metrics as of v0 3 PMV and PPD can be calculated o If Comfort calc is selected a number of further dialogues appear to control the work efficiency air velo city and clothing levels and turn on CO monitoring Scheduling for most parameters in this node can be turned on by connecting a schedule node to the appropri ate input schedule socket The node contains 5 schedule input sockets OSchedule for the specification of the occupancy schedule ASchedule for the specification of the occupant activity metabolic rate WSchedule for the specification of the work efficiency schedule VSchedule for specification of the air velocity schedule and CSchedule for the specification of the clothing schedule 4 7 4 The EnVi Equipment node The EnVi Equipment node specifies the equipment level as internal heat gain for the zone represented by the connected zone node An example of such a connection is s
13. red near the horizon white near noon As the sky background is much further away from the 3D viewpoint than the sun and the sun path mesh then if the viewpoint is not near the centre of the sun path mesh there will be a misalignment between the sun and the brightness of the sky background To rectify this a SkyMesh is also created but is hidden by default This sky mesh is a sphere the surface of which sits just outside sun path mesh If in Cycles rendering mode unhide the sky mesh and select Emission as the surface for the SkyMesh material select Sky Texture for colour and select Texture Coordinate Normal for the vector setting When the 3D viewpoint is now inside this sky mesh sphere the sky texture will be projected onto the inside of the sphere in accordance with the sun position and will line up more closely with the sun path mesh itself GBR_London Day of year Hour of year Display hours Font size Font shadow Figure 29 Sun Path visualisation options Dr Ryan Southall 23 School of Art Design Media VI Suite v0 3 5 Using the VI Suite 5 2 Wind Rose Creation Projecting a wind rose into the scene also requires a VI Location node In this case however the location node provides wind speed and direction data for the wind rose analysis and therefore an EPW file must be chosen as the source of information within the loc ation node A typical node set up is shown in figure 30 The option
14. selected object may be required to correctly calculate which points are visible O Font size colour shadow controls the number display o Position offset controls the offset point for the numerical display in general should be set to the same value as the offset value in the LiVi Geometry node The Display active option at the bottom turns off result display This should be used when results display is no longer required as using Blender s undo feature can crash Blender if this is left on Ifa compliance analysis was undertaken and extra section is presented figure 38 to control the compliance panel display Dr Ryan Southall 29 School of Art Design amp Media VI Suite v0 3 5 Using the VI Suite In this section the first option is to turn on the compliance panel and the next 4 options allow the user to enter text strings Compliance Panel with project specific information Assessing organisation As Asessment organisation sessing individual Job number and Project name Enabling the Assesment individiual compliance panel will show a table at the top left of the 3D view Job number that displays the relevant metric benchmarks to be achieved Project name the actual value achieved whether this constitutes a pass or fail and the number of credits achieved The total number of credits Figure 38 Additional LiVi Compliance dis achieved box assumes that all spaces in a project that need to play options show com
15. v0 3 4 The Vi Suite Interface 4 3 Common Nodes Common nodes are nodes that do not belong to any particular simulation pipeline 4 3 1 The VI Location node A VI Location node can be added from the Add Input nodes menu entry The Vi Location node sets the location of the context to be analysed in terms of latitude and longitude and if required hourly weather data from an EPW format weather file This Manual node is a required node for sun path solar shading EPW wind rose energy and most lighting analyses The source of the information provided by this node can either be entered manually by the user ad a b equate for sun path solar shading and some lighting analyses or generated from an EnergyPlus weather Figure 6 VI Location node a with manual entry b EPW file required for wind rose energy and CBDM sourcing EPW weather file analyses but can be used for any location based ana lysis type This choice is made with the nodes first drop down menu If the Manual option is chosen here then the user can enter site latitude and longitude 180 to 180 degrees with West of the Greenwich meridian having positive values in the two number dia logues If EPW is chosen then a new drop down menu appears with a list of registered EPW files EPW files are registered by placing them in the EPFiles Weather folder within Vi Suite script folder and restarting Blender The EPW files should have a epw or EPW extension A g
16. E EHS DROS OS 15 461 The EnVi Geometry node 2 lt 665 oo or ks Bee awe es been as 15 O52 TheEnViExportnod lt lt cisco ao 498 8 a ew Resa ee 15 4 6 3 The EnVi Simulation node 16 4 7 EuviNetworkNOUSS 46 2 6 5 Sb ew Ewe oe A OO eR a a 17 4 7 1 The EnVi Zone nodes eee es 17 d d The EnVi HVAC node eee ee 18 473 The EnVi Occupancy node suae a ew OEE CREE 19 474 The EnVi Equipment node osa ias 19 4 7 5 The EnVi Infiltration node 20 4 7 6 The EnVi Control node 20 Elda TheEnvVi WPC Array node eos soria par A 20 4 7 8 The EnVi Schedule node 20 4 7 9 The EnVi Surface Flow node 21 4 7 10 TheEnViSub surfaceFlownode 22 4 7 11 TheBnViExtermal node 4 ooo eR X a ODORS mh 22 4 7 12 The EnVi Reference Crack Conditions node 22 5 Ibba NEV U eeri oe ee beh a 9 omo OS sara da y eS ox 23 Bl Sun Path PIDE su teehee eR EEE EEE EASES REIN SUE ESE e OS 23 t CONTENTS VI Suite v0 3 5 2 Wind R se Creation 4 64 4 44645 6 ue or 24 Do ONON el kk PEUT 24 5 4 LiVi Lighting Analysis 2424 ics E o9 RO POE whee 308 803 X 30979 Ew EEE A SSD ES 26 Bl E 232639393 4339033 4E PG 3 EE PEELE SEES 26 dad EVI creation uuo xau mes doe EE GERE eS EG dEXSNuSs ES 27 DL LVS acordeones hee ee m xo EE RE e
17. LiVi Geometry Export node figure 14 exports Blender geometry and materiality to a format that can be under stood by the Radiance lighting simulation suite All unhid den lights geometry and materials on the current Blender layer are exported and the Radiance description stored within the node If the animation option is selected a description for each valid frame is written The options Vertices within the node define whether the geometry is to be an imated the frame range for the animation and the point on any sensing geometry at which results will be calcu lated vertices or faces The node has one output socket that can connect to a Text or Geometry in socket Figure 14 LiVi Geometry node 4 5 2 TheLiVi Context node Basic IIlu Irrad DF Compliance CBDM Light Exposure Sunny BREEAM School dy lt P gt gt Single Export a Basic analysis b Compliance analysis c CBDM analysis Figure 15 LiVi Context node The LiVi Context node figure 15 controls the export of a lighting simulation context to a text format that Radiance can understand In terms of a Radiance simulation context means the type of sky the building is exposed to the time of day and year and the metric to be calculated On export the sky context is stored within the node This node can create three different categories of sky context Basic for simple lighting metrics Compliance for checking against lighting standards B
18. REEAM and Code for Sustainable Homes are currently supported and CBDM for climate based daylight modelling The node has one input socket and one output socket The input socket is a Location in socket for connec tion to a VI location node s Location out socket The output socket is a Context out socket for connection to a Text socket or a LiVi Simulation Context in socket Node options are dynamic and presented only if appropriate for the type of analysis selected Some of the options are o Analysis type Basic Dr Ryan Southall 13 School of Art Design amp Media VI Suite v0 3 4 The Vi Suite Interface Allows calculation of illuminance irradiance Daylight Factor amp glare Sky type options Sunny partly cloudy cloudy Daylight Factor HDR amp Radiance sky The latter two allow the selection of an HDR panorama image or a Radiance sky description file respectively Animation options Only available if a sunny partly cloudy or cloudy sky is selected If animation is chosen Blender animation frames will be created from the selected starting frame option end frame is calculated automatically Time options Start hour day only available if a sunny partly cloudy or cloudy sky is selected in the sky option and end hour day and interval only available if animation is selected o Analysis type Compliance Allows assessment of complaince against BREEAM and CfSH startndards o Analysis t
19. Simulations and Visualisations with the VI Suite For VI Suite Version 0 3 Dr Ryan Southall School of Art Design amp Media University of Brighton Contents Lo BRIDE o sua 8 wo Rd RORUX OP ACROSS NOU wo ED SO ROS OEE He A EM a edit d d 3 CODI rara ERGO RO e t lt EE ERDAS OE EEE SO 4 U o AS 4 Ll TIMONE lt a ORO ES ROBE EKA ESE wADE SEAS TERESA HORE SS BOS 4 2 3 fos A 5 0 ALDPISEDEHTS A xu ow we OR dr a OR OS 9 de e p A OR OLOR OA Se 3 5 E 0 0 o0 E III 6 4 The Vi Suite Interface eee es 7 Oi o a MM IE 7 d2 Vis alsaton panel ack esa tbe dk Yo bo oye A 8 LS Common Nodes ic wee eG de Oh OES SOE ERASE CERES KH 9 4 3 1 The VI Location node ess 9 Ope Ihen3L Import node coc armas a um Rey e Ee x e Ge 9 4 3 3 TheEnViResultsFilenode cen 10 4 3 4 Ihe VIL BAPEBOO uuo ov wee Rw RE NL Owe rada RRO ES 10 44 Specific Analysis Nodes i mm gor GRO EEE SRE SERRE ROCA EEE OOD ES 11 4 4 1 The Vi Wind Rose node c ees 11 4 4 2 The Vi Sun Path node uus 45 5A48 OR cR tede eR OST EOD EE EBS 11 4 43 The Vi Shadow Study node o een 11 45 IAVUNOOES 265699 sarria 4 XZom ROW WO ER ch eR EERE RR HERES SOS 13 4 5 1 The LiVi Geometry Export node eee es 13 4 5 2 The LiVi Contextnode ce ee ss 13 4 5 3 The LiVi Simulation node ae amp hx Swe a a 308 SR Oe wR d 14 46 ENVIOS on kth we oe Hew OES ESSE EERO OE
20. adiance software simulation suite A valid Radiance installation is therefore required on the host machine unless the pre packaged zip files are used which contains the required Radiance files Details of the installation process can be found in section 2 There are five main LiVi nodes LiVi Geometry LiVi Context and LiVi Simulation All are detailed in section 4 5 A LiVi analysis will require a LiVi Geometry node LiVi Context and a LiVi Simulation node A numerical LiVi lighting analysis like a shadow study requires geometry within the scene to be identified as sensing geometry This is done in the material panel within the Vi Suite Material section where the option LiVi Sensor should be selected in the Material type drop down list All geometry to which this material is associated will now act as a sensing plane Exceptions to this requirement is if a glare study or only a preview of the Radiance scene is to be conducted The sensing geometry senses in the direction of the Blender sensing face or vertex normals 5 4 1 LiVi Geometry The LiVi Geometry node which can be found in the Add Export Nodes menu of the VI Suite node editor controls the export of the of the Blender scene geometry and materiality to the Radiance text file format Only geometry on the current Blender layer is exported meaning that a number of different scene scenarios can be set up on different Blender layers Within a layer any geometry that is not hidden an
21. an Southall 26 School of Art Design amp Media VI Suite v0 3 5 Using the VI Suite oun TragjUr n Manual zl Latitude 48 73 Longitude 2 40 Figure 35 Typical LiVi node set up option is selected Any animation of geometry material or lighting set up within Blender for the selected frame range will be simulated 5 4 2 LiVi Context creation A basic analysis allows for the prediction of illuminance lux irradiance W m Daylight Factor 96 and glare The first three metrics are plotted onto sensing planes in a similar manner to the shadow study analysis using the rtrace component of Radiance A typical node set up is shown in figure 35 A lighting compliance analysis can be selected from the Context menu of the LiVi Context node A LiVi compliance analysis checks lighting performance against internationally recognised standards As of VI Suite version 0 3 compliance with BREEAM HEAI and Code for Sustainable Homes can be assessed Once a LiVi compliance context has been exported a compliance specific drop down menu is exposed within the VI Suite Material tab of the material panel to define the type of space a particular sensing material is associated with For a BREEAM residential property for example this option can select a Kitchen Living Dining or Communal space A Climate Based Daylight Modelling CBDM analysis can be selected from the Context menu in the LiVi Context node and a
22. ategory drop down menu The node has two input sockets Geometry in for con nection to an EnVi geometry node s Geometry out socket and Location in to connect to a VI location node s Locaton out socket and one output socket Context out for connection to an EnVi Simulation node s Context in socket The connected VI Location node must have EPW selected as its information source If valid input socket connections are made an Export button will appear at the bottom of the node Figure 18 EnVi Export node Specific options are o Name location provides a text box for the optional entry of an EnergyPlus project name o Terrain specifies the type of terrain the building sits in o Start end month specifies the beginning and end month for the simulation o Time steps specifies the number of simulation time steps per hour Dr Ryan Southall 15 School of Art Design amp Media VI Suite v0 3 4 The Vi Suite Interface o Results category chooses the class of metrics to be calculated Options are Zone Thermal Comfort Zone Ventilation Ventilation Link o Individual tick boxes for specific metrics within the chosen results category class Upon pressing this the in idf file is created in the project directory and the Context out socket will become visible 4 6 3 The EnVi Simulation node The EnVi Simulation node figure 19 initiates an EnergyPlus simulation The EnVi Simulatio
23. d by John Blain available here and good on line video tutorials available here and here In addition there is a wealth of books 1 2 3 websites and You Tube and Vimeo videos dealing with many aspects of Blender s capabilities The Blender Artists forum at http blenderartists org forum is an excellent resource for finding out what other people are doing with Blender and asking questions of knowledgeable users Outliner 3D View Material panel Properties panels Timeline Figure 2 Blender interface The VI Suite is an add on to Blender and will need to be activated on a fresh install This can be done from Blender s user preferences Go to File menu at the top of the 3D view and from the drop down list select User Preferences Along the top of the new preferences window there will be an Addons tab Click on this and then scroll down and select the VI Suite by clicking on the box on the right of the VI Suite entry It may take a couple of seconds for the box to show a tick indicating that the VI Suite has been registered There are other settings within the User Preferences that can be altered as desired for example to control how the 3D view is navigated The resources above contain sections on customising the Blender user interface By default the 3D view can be rotated with the middle mouse button zoomed with the mouse wheel and objects are selected with the right mouse button it is recommended to c
24. d has at least one material associated with it will be exported Upon pressing the node s Export button the node first converts Blender materials to Radiance mater ial descriptions Specification of the Radiance material type for a particular Blender material is done within Blender s material panel At the bottom of the material panel a section called VI Material Type presents a drop down menu called LiVi Radiance type that allows the designation of the Radiance material type for the selected Blender material Options include Plastic Metal Glass etc Options to further specify the Radi ance material are then presented Next suitable geometry is exported as obj files to the obj folder created in the project directory The obj files are then automatically converted to Radiance mesh files with Radiance s obj2mesh program and referenced within the Radiance input text Actual object vertex co ordinates are instead written out to the Radiance input if a Blender object s geometry is non manifold i e not physically realisable e g an edge without faces or if a Mirror or an Emission material is associated with an object as Radiance meshes cannot have these material attached Next Blender lights are exported to Radiance format There are two ways to set up lights for Radiance ex port Creating standard Blender lamps or creating a plane at each face of which a lamp is automatically spe cified If using the first method then selecting a
25. e user name is your user name and blender version is the version of Blender downloaded currently 2 76 Create within this directory a scripts directory and within this an addons directory all lowercase The VI Suite Python files are available as a down loadable zip file from the VI Suite website which can be found at http arts brighton ac uk projects vi suite downloads The vi suite folder within the zip file should be placed in the Users user name Library Application Support Blender blender version scripts addons folder created earlier Download Radiance from https github com NREL Radiance releases and run the Radiance installer The VI Suite assumes Radiance is installed to the folder locations usr local radiance A recent version of Ra diance 5 0 or above is required Download and install EnergyPlus v8 4 from https github com NREL EnergyPlus releases The VI Suite assumes EnergyPlus is installed in the Applications EnergyPlus 8 4 0 directory As of Blender version 2 76 Numpy is included with Blender but a number of other dependencies namely pyparsing six sip dateutils distutils and pylab are required for full matplotlib functionality Installing all these dependencies is troublesome but the easiest method would appear to be installing a Python 3 4 distribution such as Anaconda https store continuum io cshop anaconda and copying the relevant files to Blender s Py thon folder If matplotlib still does not work try typ
26. ealed in the Figure 11 VI Wind Rose node VI Display tab section 4 2 Create Wind Rose 4 4 2 The Vi Sun Path node The VI Sun Path node shown in figure 12 creates objects within the Blender scene for sun path visualisation section 5 1 These objects include the sun path mesh itself sun lamp sun mesh and sky mesh These objects can be moved around the scene as desired As the sun path analysis requires latitude and longitude data this node has one input socket Location in which con nects to a VI Location nodes Location out socket As only latitude and longitude data is required either EPW or manual data input can be used in the VI Location node connected to the Location in socket The node contains no options simply a button which is only visible once a valid Location in socket connection has been made to create the sun path geometry Once this button is pressed and the sun path objects created options appear in the VI Suite Display tab section 4 2 to control the day time and size of the sun path objects for real time visualisation of sun position Create Sun Path Figure 12 VI Sun Path node 4 4 3 TheVi Shadow Study node The VI Shadow Study node figure 13 grey scale colours sensing geometry based on the proportion of time the geometry is exposed to direct sunshine assuming clear sky conditions The calculation is done every specified interval during month and hour range specified if the sun is above t
27. ed on by entering bpy app debug True into Blender s python console window Boundary sockets must be connected to another boundary socket on another zone node Surface and sub surface flow sockets must be connected to an EnVi Surface flow node or an EnVi Sub surface flow node respectively An additional input socket VASchedule is optional and allows the specification of a venting availability schedule for the zone If an airflow or boundary socket on one side of the node is connected it will disappear from the other side of the node When all airflow boundary sockets are either connected or hid den the node becomes valid and will turn the default colour It should be noted that any EnVi zone must have at least two air flow surfaces specified within it and at least two sets of flow sockets should appear in the node The node also displays the name of the Blender object EnergyPlus zone the calculated volume of the node and the ventilation control type Control types are None Constant and Temperature If Temperature is selected a new input socket TSPSchedule must be connected to an EnVi schedule node This schedule will set thermostat temperature set points above which the zone airflow connections will all considered to be fully open Some extra options are then also displayed Figure 20 EnVi Zone node o Minimum OF the minimum opening factor of the ventilation flow surfaces o Lower the lower temperature difference thres
28. etween the two zones If only one socket is connected to an EnVi zone node the surface flow is assumed to sit on the external boundary of the zone and control airflow between inside and outside An additional socket is the VASchedule input socket which allows for the specification of a venting availability schedule for the component If the Control type option is set to Temperature an extra socket is created to allow a thermostat schedule to be specified Simple Opening y Options in this node include 0 10 ZoneLevel o Type the type of flow component simple opening de tailed opening horizontal opening effective leakage area or crack o Subsequent options control the parameters of the selec ted component type Refer to the EnergyPlus input out put reference file for further details Figure 27 EnVi Sub surface flow node 4 7 11 The EnVi External node The EnVi External node provides wind pressure coefficients for the outside surfaces of the building These nodes are only required if the WPC type option in the EnVi control node is set to Input The node has sub surface flow and a surface flow sockets as both inputs and outputs Joining these sockets to a flow component specifies the building wind pressure coefficients for the angles spe cified by a WPC Array node A WPC Array is therefore required to be connected to the EnVi control node for these nodes to be valid 4 7 12 The EnVi Reference Crack Conditions node
29. gn amp Media VI Suite v0 3 6 Known issues All of these zone specification nodes can be found in the Add Zone nodes menu at the bottom of the node editor 5 5 5 EnvVi network creation EnVi network creation allows connections between zones airflow and physical to be defined A physical con nection would for example represent a boundary wall or floor ceiling between two zones that heat can flow across Air flow boundaries allow air to flow between zones or between zones and the outside For any EnVi zone faces that have a material with the On boundary or Airflow surface property the zone node created in the EnVi Network tree will contain sockets auto generated to represent the airflow or boundary faces within the zone It is then simply a case of connecting the sockets between nodes to represent ventilation or physical boundaries between spaces For example if a face within a Blender object has a Blender material associated with it and the Airflow surface option has been turned on for this material sockets will appear within the created zone node for these airflow surfaces If the material associated with this face is a window or door green sub surface sockets are created for connection to a sub surface flow node If the material associated with this face is a wall floor or ceiling red surface sockets are created for connection to a surface flow node 5 5 6 EnVi schedule specification The node to specify a schedule
30. gov Thanks to Tony Graham for his feedback on this manual Dr Ryan Southall 34 School of Art Design amp Media Bibliography 1 J M Blain The Complete Guide to Blender Graphics Computer Modeling and Animation Taylor amp Francis 2012 2 G Fisher Blender 3D Basics Community experience distilled Packt Publishing Limited 2012 3 R Hess Blender Foundations The Essential Guide to Learning Blender 2 5 Taylor amp Francis 2013 35
31. hange this to left mouse button select in the user preferences Input tab Once the VI Suite addon has been activated and any other changes have been made click Save User Settings to make these choices permanent Once the VI Suite has been activated it sits within Blender s node editor The Blender interface is in general what s called a non overlapping interface i e interface areas sit side by side rather than on top of each other Any area can be turned into any other area type by selecting the type from the drop down menu at the left hand side of the area s header bar which sits either at the bottom or the top of each area For example the time line can be turned into the node editor by selecting Node Editor in the drop down menu in the very bottom left of the time line area Dr Ryan Southall 6 School of Art Design amp Media VI Suite v0 3 4 The Vi Suite Interface 4 The Vi Suite Interface 4 1 The Node System The VI Suite uses Blender s user customisable node system to provide a flexible user interface The node editor view figure 3 can be panned with the middle mouse button and zoomed with the mouse scroll wheel Nodes can be added deleted moved re sized collapsed grouped linked and unlinked Once a VI Suite node tree has been created nodes can be added using the Add menu item at the bottom of the node editor There are six node categories o Input nodes that import data into the VI Suite O Export nodes that
32. he horizon White means exposed to sun shine 100 of the time and black 0 of the time The node has one input socket Location in which connects to a VI location nodes Location out socket Node options include Dr Ryan Southall 11 School of Art Design Media VI Suite v0 3 Oo Oo Oo Oo Oo Animation to specify whether geometry is animated or static Start 8 end month to specify the month range Start amp end hour to specify the daily hour range Interval in hours to specify the time between calcula tions 0 5 would be 30 minutes Result point to specify if the shadow sensing points are positioned at the face centre of vertices of the sensing ob ject Offset to specify the distance of the sensing point from the geometry this is useful if the sensing mesh has non planar faces that would place the centre of the face below the face surface Dr Ryan Southall 12 4 The Vi Suite Interface Static Calculate Figure 13 VI Shadow Study node School of Art Design amp Media VI Suite v0 3 4 The Vi Suite Interface 4 5 LiVi Nodes The lighting analysis nodes control and specify a LiVi simulation for the prediction of lighting metrics Most of the lighting analysis nodes LiVi Geometry LiVi Basic LiVi Compliance and LiVi CBDM can be added via the Export nodes menu LiVi Simulation can be added from the Analysis nodes menu 4 5 TheLiVi Geometry Export node The
33. hold o Upper the upper temperature difference threshold See the EnergyPlus input output reference file for details on these options Dr Ryan Southall 17 School of Art Design amp Media VI Suite v0 3 4 The Vi Suite Interface 4 7 2 The EnVi HVAC node The EnVi HVAC node can created from the Add Zone Nodes menu and controls the heating and cooling for the zone represented by the connected EnVi Zone node An example of such a connection is shown in figure 21 As EnergyPlus is developed in America where the heating and cooling of spaces with air is common the options within the HVAC node specify the temperature flow rates and heating cooling capacity of the incoming air Figure 21 EnVi HVAC specification Node options are o HVAC Template whether an HVAC template should be used as of v0 3 only an ideal load air system has been implemented Oo Heating limit What type of heating limit is applied to the zone Options are None no heating No limit no limit to the heating capacity of the system LimitFlowRateandCapacity specify both the air flow limit and the heating capacity of the system LimitCapacity limit only the heating capacity of the system and LimitFlow only limit the heating air flow rate Oo Heating temp The temperature of the heating airflow O Heating airflow if a Heating limit has been set that limits air flow this maximum air flow value is set here o Heating capacit
34. hown in figure 23 Dr Ryan Southall 19 School of Art Design amp Media VI Suite v0 3 4 The Vi Suite Interface Figure 23 EnVi Equipment specification The node sets the type and level of the internal equipment heat gain The node has one input schedule socket for the specification of the equipment schedule 4 7 5 The EnVi Infiltration node Ifno advanced air flow network is created then simple air infiltration for the zone represented by the connected EnVi Zone node can be specified here An example of such a connection is shown in figure 24 98 26 Figure 24 EnVi Infiltration specification The node sets the infiltration type and level and contains one input schedule socket Schedue for the specification of the infiltration schedule 4 7 6 The EnVi Control node The EnVi control node is created automatically within the EnVi network node tree during EnVi geometry con version if a Blender object EnergyPlus zone contains air flow surfaces The EnVi control node specifies the high level options for the ventilation network For more details of these options refer to the EnergyPlus input output reference document An important option here is WPC type which if set to Input requires an array of wind pressure coefficients to be specified The wind angles for these values are specified with a WPC Array node at tached to the WPC Array socket of the control node EnVi External nodes attached EnVi Surface flow and EnVi Sub
35. in EnVi consists of the following options An End day dialog which takes a number from 1 to 365 a Fors dialog which takes text and an Untils dialogue which also takes text The dialogues along with sample entries are shown in figure 41 The first dialog sets the end day of the year that each sub schedule applies to the start day is as sumed to be the first day of the year The second sets the types of day that the schedule applies to with a space separated list of consisting of any of AllDays Weekdays Weekends Monday Tuesday Wednesday Thursday Friday Saturday Sunday AllOtherDays Day types should not overlap e g placing Weekdays la 365 Tuesday in the text box will cause an error as any Tuesday would be valid for both schedule days The final box contains the semi colon separated hour ranges for each day type of the sub schedule In the example in figure 41 up to day 90 of the year for all days the schedule is 0 from midnight always the automatic schedule starting time up to 8 in the morning 1 until 6 in the afternoon and 0 again up to mid night For day 90 to 365 on weekdays the schedule is 1 all day and on weekends the schedule is 0 up to 8 in the morning and 1 up to midnight Each time value pair is separated by a comma Figure 41 EnVi schedule dialogues 6 Knownissues O Only line scatter graphs can be plotted from the VI Chart node O Animated EnVi analysis is not currently possible
36. in VI Suite components LiVi which acts as a pre post processor for the Radiance lighting simulation suite and EnVi which does the same for the EnergyPlus v8 4 thermal simulation engine Vertices P Manual y Medium Basic Illu Irrad DF None Figure 1 Blender nodes Dr Ryan Southall 3 School of Art Design amp Media VI Suite v0 3 2 Installation 2 Installation Prepackaged VI Suite zip files for Windows and Mac OS X can be downloaded from the VI Suite website http arts brighton ac uk projects vi suite downloads The zip file can be extracted to anywhere on the host computer and the Blender executable run from the created directory As there are so many different Linux distributions and the required software installation is relatively simple no complete packaged file is provided for this platform A VI Suite zip file which includes all the VI Suite specific files can however be downloaded from the VI Suite website and moved to the Blender addons directory If a manual installation of the separate components is preferred platform specific installation guidelines can be found below 2 OSX The VI Suite has been tested on OS X Version 10 10 64bit First download Blender from http www blender org download and install Run Blender once and se lect File Save Start Up File to make sure the Blender configuration directory is created at Users user name Library Application Support Blender blender version wher
37. ing import matplotlib pyplot as plt in Blender s Python com mand window Any error message should say which Python library is missing It is also advisable to use a three button mouse which is set up as a three button mouse in OS X 2 2 Windows VI Suite has been tested on a 64bit Windows 7 system although the Radiance and Blender binaries are both 32bit and should run on older 32bit Windows versions First download the Blender zip file from http www blender org download The folder within this zip file can be moved to anywhere on your system as long as there are no spaces in the full directory path The folder is subsequently referred to here as the blender folder Run Blender once and select File Save Start Up File to make sure the Blender configura tion directory is created at C Users user name AppData Roaming Blender Foundation Blender blender version where user name is your user name and blender_version is the version number of the downloaded Blender version 2 76 at the time of writing Create within this directory a scripts directory and within this an addons directory all lowercase Then download Radiance 5 0 from https github com NREL Radiance releases and install Vi Suite assumes that Radiance is installed in the C Program Files x86 Radiance folder for 64bit windows and C Program Files Radiance for 32bit windows A recent version of Radiance 5 0 or above is required Download and install EnergyPlus v8 4 f
38. l ground and upper storey floor constructions o Roof Typical roof constructions o Door External and internal door constructions o Shading External shading surfaces o None No EnVi construction type Once a type has been selected options will appear below to choose a pre stored construction or to define a construction by the specification of the construction layers Pre defined construction choices are currently quite limited but new ones can be added as detailed in section 5 5 3 and any custom material or construction created will be remembered within the Blender file Custom materials require the input of all the material characteristics There can be up to 5 layers in a construction Each layer has a thickness and characteristics such as density and thermal conductivity It is because of these properties that EnergyPlus only needs planar geometry to be able to describe a complete building Each Blender material and its associated EnVi construction designation can be applied to individual faces of Blender objects If the Blender object geometry is complex the materials should only be applied to the in terior surfaces of the zone There are three more toggle options within the EnVi material panel Intrazone boundary Airflow sur face and Thermal mass The first tell EnVi that a surface shares a boundary with another zone This might Dr Ryan Southall 31 School of Art Design amp Media VI Suite v0 3 5 Using the VI Suite
39. lamp within Blender will display a LiVi IES File section at the bottom of the Lamp properties panel In this section it is possible to specify an IES file to associate with the Blender lamp IES files are released by luminaire and lamp manufacturers and describe the brightness of a luminaire or lamp from multiple directions The desired IES can be picked with the Select IES File button Three additional options are also presented o ES Dimension specifies the distance unit for the geometry described in the file o IES Strength which allows the light to be dimmed can be animated o IES Colour sets the colour of the lamp can also be animated The second method allows any selected mesh object to have an IES file associated with it via the LiVi IES file section of the Object data panel Any IES file selected here will now be applied in the Radiance scene at each face centre of the mesh object This is useful for quickly setting up arrays of lights Radiance material geometry and light descriptions are finally written as text and stored within the node If an object with a LiVi sensor material is exported the sensing point co ordinates are written to the blender filename rtrace file and saved in the project directory If undertaking an animated analysis LiVi will export a Radiance scene for each frame from Blenders start frame to end frame The range of frames considered for analysis can be set within the node if the Animated Dr Ry
40. llows the lighting performance of a building over longer periods of time to be analysed The information for the environmental lighting conditions is provided at least initially by a location node taking an EPW file as its source of information 5 4 3 LiVi Simulation A complete node set up for a LiVi simulation is shown in figure 35 The simulation node initiates either a visual isation preview of the Radiance model from the point of view of the Blender camera with the Preview button or the Radiance simulation with the Calculate button Once the Calculate button is pressed the Radiance sim ulation is initialised and when finished the Blender interface will lock up while the simulation runs unless a glare analysis has been selected display options appear in the VI Display section of the 3D view properties panel These display options are detailed in section 5 4 5 When completed the Radiance results are stored within the meshes of the sensing geometry for visualisation Options in the VI Display panel detailed in sec tion 5 4 5 control visualisation of these results unless a glare analysis has been selected Glare analysis has a different visualisation process also detailed in section 5 4 5 Dr Ryan Southall 27 School of Art Design amp Media VI Suite v0 3 5 Using the VI Suite a Without Photon Mapping b With Photon Mapping 500 000 global photons and 5 000 000 caustic photons Figure 36 One Photon map to rule them all
41. lues Legend scale switches result colouration and 3D result extrusion between lineal and log log is useful when there is a large difference between the maximum and minimum results for example when the sun is shining directly on part of the sensing surface Draw wire toggles the display of a wire frame for the se lected object May need to be selected twice to turn on the wire frame 3D Level only appears if VI 3D display option was chosen controls the level of 3D extrusion of the results geometry Transparency set the transparency level of the result geo metry 5 Using the VI Suite Y Vi Suite Display VI 3D display l Radiance Display Only Render Legend v Legend max 2617 44 Legend min d 1253 72 Legend scale log Draw wire v 3D Level k 0 30 Transparency 1 00 Point visualisation Enable Selected only Visible only Font size g Font colour MO Font shadow A y 0 001 Position offset pre re pe eee re ne es mee e emm Display active 4 Figure 37 VI Display options The next section controls the display of numerical result values for each point of the sensing geometry Options in this section include O Enable toggles numeric display o Selected only display numerical results only on the selected geometry o Visible only only the sensing geometry points visible within the 3D view display numerical values ori entating the view to the
42. me available in the 3D view properties panel in the VI Display tab section 4 2 These options are not presented as nodes as they influ ence the 3D view display and therefore have to sit in the 3D view properties panel 4 2 Visualisation panel Control of the visualisation of results within Blender s 3D View is done within 3D view properties panel This panel can be toggled on and off by pressing the n key with the mouse over the 3D view Alternatively you should see a small sign in the top right of the 3D view Clicking on this will also open the 3D view prop erties panel At the bottom of this panel is the VI Suite Display tab figure 5 which will get populated with visualisation options as they become available Q File Render Window Help TX Cycles Render v2 73 Verts 12 572 Faces 12 592 Trig gt Display gt Shading e LY d gt Motion Tracking saec gO ia 6 O Y QU etia um y gt Background Images I9 o gt Transform Orientations Y p i Be 6 Y EI D fs os ho Properties NA dt Ec WN MERERI NA iussu KK sae A e Shadow Display Legend FEE Draw wire Y aN 3D Level Transparen Point visualisat Enable Selected only Visible only Font size Font colour Font shadow Position offs 0 Planeres 0 QU View Select Add Object f ObjectMode Figure 5 VI Suite Display tab Dr Ryan Southall 8 School of Art Design amp Media VI Suite
43. n node has two sockets Con text in for connection to another node s Context out socket and Results out for connection to a VI Chart node or a VI CSV Export node The node contains a text box into which the name of the EnergyPlus results file default is results can be specified This file with the extension eso is saved in the pro ject directory Once a valid socket connection has been made to the Context in socket a Calculate button appears which when pressed initiates the EnergyPlus simulation The node will then turn red and will monitor the EnergyPlus simulation and give a prediction of simulation progress The Blender interface should remain interactive during simulation When the simula tion is finished results can either be plotted or exported in CSV format by connecting a VI Chart node or VI CSV node to the Res ults out socket Dr Ryan Southall 16 results Calculate Figure 19 EnVi Simulation node School of Art Design amp Media VI Suite v0 3 4 The Vi Suite Interface 4 7 EnVi Network Nodes EnVi Network Nodes are used within the EnVi Network node tree to specify zone schedules and natural ventila tion networks For details of the meaning of the options presented by these nodes see the EnergyPlus reference document http nrel github io EnergyPlus InputOutputReference 01d InputOutputReference 4 7 1 The EnVi Zone nodes EnVi zone nodes are created automatically in the EnVi Network n
44. nder to see the system Python installation 2 4 All Platforms Once the whole VI Suite has been downloaded and installed bug fix updates of the actual Python VI Suite scripts can be downloaded checking out the code from the github repository Go to https github com rgsouthall vi suite v03 and click on the Download ZIP button on the right Bleeding edge code and I really do mean Bleeding Edge can be found in the v04 repository https github com rgsouthall vi suite v04 Once the repository is selected the latest code can be downloaded with the zip link at the top of the github page Dr Ryan Southall 5 School of Art Design Media VI Suite v0 3 3 Configuration 3 Configuration Running Blender launches the main Blender interface which should look similar to the one shown in figure 2 The main window is the 3D view where the default cube lamp and camera can be seen Below this is the animation time line on the top right is the project outliner that contains a list of everything in the scene and bottom right are the properties panels where many of Blender s options and functions reside At the top of the properties panel window are tabs to control which panel is visible The main panels used in the VI Suite are the Material and Object data panels Detailed instructions on how to use Blender are beyond the scope of this document but there are excellent and free beginners documents available by James Chronister available here an
45. ode tree during EnVi geometry conversion Input sockets are created for HVAC occupancy equipment and infiltration specification If a Blender object s material has the airflow surface or boundary surface option turned on sockets are also created for these sur faces These sockets are coloured brown if representing a boundary surface green if representing a sub surface flow component associated with opening surfaces like windows or doors and red for a surface flow associated non opening surfaces such as walls floors and roofs These sockets are created on both sides of the node for easier arrangement of connections within the node editor The example in figure 20 shows a zone with two sub surface flow faces green sockets associated with the zone and a one boundary face brown socket The node is coloured red as there are no connections to these sockets The three flow and bound ary surfaces express themselves with socket names derived from the name of the material associated with the surface the index number of the Blender face and an s to denote a surface flow or ss to denote a sub surface flow or a b to denote a bound en Cube 001 ary surface For example en window 4 ss denotes that Blender 61 01 material en window is associated with a face the face has in in dex of 4 and it represents a sub surface flow The VI Suite it None self does not currently visualise face index numbers but face in dex visualisation can be turn
46. of global diffusely reflected and caustic specularly reflected Photons can be set In the example shown in figure 36 global photons were set to 500 000 and the caustic photons set to 5 000 000 If previewing the scene with Preview button the rvu window will not appear until the required number of photons have interacted with the relevant geometry Dr Ryan Southall 28 School of Art Design amp Media VI Suite v0 3 5 4 5 LiVi Display Apart for a LiVi Basic glare analysis LiVi display options are presented within the VI Display section of the 3D View s prop erties panel toggled with the n key over the 3D display A basic VI Display section is shown in figure 37 Initially only the VI 3D display toggle and the Radiance Display button are shown The VI 3D display toggle controls whether a 3D display of the results metric is desired Once the Radiance Display button is pressed new Blender objects will be created coloured according to the Radiance results and fur ther options are presented These options include O O O Only Render toggles the display of the 3D cursor axis wire frames and object manipulators Legend toggles the display of the legend Legend max min specifies the the maximum and min imum value for the legend and colour display placing the mouse cursor over the top or bottom of the legend in the 3D display and scrolling with the mouse wheel will also alter the legend max min va
47. on default thickness mm A material in the glass category may look like Clear Gm Glazing SpectralAverage 0 006 0 775 0 071 0 071 0 881 0 080 0 080 0 0 0 84 0 84 0 9 Only the numbers within the brackets generally need to be changed and they represent default thickness m solar transmittance at normal incidence front side solar reflectance at normal incidence back side solar reflectance at normal incidence visible transmittance at normal incidence front side visible reflectance at normal incidence back side visible reflectance at normal incidence IR transmittance at normal incidence front side IR hemispherical emissivity back side IR hemispherical emissivity and thermal conductivity W m K In the class envi constructions additional preset multi layer constructions can be specified 5 5 4 EnVi zone specification An object in Blender in terms of EnergyPlus can either represent nothing a thermal zone or shading geometry This selection is made in Object Data panel within the EnVi Zone Definition tab If thermal is chosen and the object has EnVi construction materials applied then upon EnVi geometry export zone nodes are created within the EnVi Network node tree An example of an EnVi zone node is shown in figure 20 To this node can be connected HVAC Occupancy Equipment and Infiltration nodes to specify the characteristics of the zone Dr Ryan Southall 32 School of Art Desi
48. on allows for the input of Ra diance command line options into the exposed text box The node also contains options for Radiance s new Photon Mapping capability section 5 4 4 Atleast version 5 of Radiance is required to use Photon Mapping Medium Figure 16 LiVi Simulation node There are two buttons in this node A Preview and a Calculate button The Preview button brings up a Radiance rvu window and renders the scene from the point of view of Blender s camera and the Calculate button initiates the rtrace simulation When the Calculate button is pressed the Blender interface will lock up during the simulation unless a glare analysis was chosen In this case the node will turn red until the simulation is completed but the Blender interface will remain interactive Dr Ryan Southall 14 School of Art Design amp Media VI Suite v0 3 4 The Vi Suite Interface 4 6 EnVi Nodes 4 6 1 The EnVi Geometry node The EnVi Export node figure 17 exports Blender scene geo metry and materiality to a form more suitable for EnergyPlus analysis which requires a very different geometry format than that typically used within Blender The node contains one Export operator button Upon pressing the Export button the node converts all unhidden geometry designated as EnVi thermal or shading zones on Blenders layer 1 and places it on Static layer 2 where it is coloured according to the construction ty
49. ood source of EnergyPlus weather files is http appsl eere energy gov buildings energyplus weatherdata_about cfm but they are a common format and can be found at many sites for a wide variety of locations The VI Location node has one output socket a green Location out socket which can connect to any green Location in socket Latitude 52 00 Longitude 0 00 GBR_London 4 3 2 The ASC Import node ASCII formatted Esri Grid files are GIS data files which can represent ground elevation data in text file format These files often have the extension asc and are referred to as ASC files here ASC files can be exported by the Edina DigiMaps web service that contain accurate terrain height data for the whole of the UK The ASC import node can be added via the Input nodes menu in the node editor The node contains two toggle options and an op erator button The toggle options are o single If on only the ASC file selected is imported If off all ASC files within the directory of the selected ASC file will be imported o splitmesh If multiple ASC file are imported this option cre Import ASC ates separate meshes for each file ASC files from DigiMaps are separated by the map grid squares selected for export Di giMaps can also supply images of roads building locations etc for each of these map grid squares and turning on splitmesh can make mapping these images to the geometry imported into Blender easier Figure 7 VI ASC
50. pe Green for roof grey for walls brown for floor turquoise for win Export dows and red for shading geometry The construction type is specified by applying Blender materials to faces of the geometry that have been given EnVi construction characteristics After changes are made to the form or materiality of any geometry on layer 1 the Export button should be re pressed to convert and copy the new geometry to layer 2 Layer 2 should then be checked to confirm the correct geometry and construction designation The node has one output socket Geometry out for connection to another EnVi node s Geometry in socket Figure 17 EnVi Geometry node 4 6 2 The EnVi Export node The EnVi Export node converts the modified Blender geometry and materiality on layer 2 into a valid EnergyPlus text descrip tion It combines this geometry data with the weather data spe cification in the connected location node and the terrain con text to create a complete EnergyPlus text input file The input file created is called in idf and is stored in the project directory which is in the same location as the saved Blender file It is also registered within Blender s text editor and can be edited before eventual simulation if required The desired individual metrics to be simulated and available later for visualisation can also be chosen here with the check boxes at the bottom of the node The check boxes shown are de pendant on the selection in the Results C
51. perty and faces with an EnVi material are exported to Layer 2 Faces are coloured according to the construction type walls are white floors are brown roofs are green windows are turquoise and shading surfaces are red 5 5 3 Storing EnVi custom constructions Within the VI Suite scripts directory is a file called envi mat py that contains all the built in material and con struction specifications accessible by EnVi Before changing this file it is a good idea to make a back up copy At the beginning of the file is a class called envi materials which contains lists of material specifications in different material categories metal brick cladding concrete wood stone gas opaque construction cavity wgas window construction cavity glass insulation If adding a material that falls under the metal category the self metal datd should for example be edited Each list is encompassed with curly brackets and contains a comma separated set of material specifications A material specification within the metal list may look like Lead Smooth 35 3 11340 128 00 0 05 0 05 0 05 5 The first word is the name of the material the first word within brackets is the surface roughness possible entries are VeryRough Rough MediumRough MediumSmooth Smooth and VerySmooth and the following numbers are thermal conductivity W m K density kg m specific heat J kg K thermal absorption solar absorption visible absorpti
52. pliance have been modelled and simulated If only a subset of spaces has been simulated this number will not reflect the credits gained for the whole building At the bottom of the 3D view another table will appear with assessing organisation assessing individual and job number displayed for the production of reports Bear in mind that the VI Suite is released as free and open source code and comes with no warranty If using the compliance analysis for consultancy work it is the responsibility of the user to ensure that the results are valid Standard CfSH Buildtype Residential Kitchen Project Name Zone Metric Achieved i 2 f Average Daylight Factor Percentage area with Skyview Credits achieved 2of2 Figure 39 LiVi Compliance panel Glare analysis differs from other LiVi analyses in that once the Calculation button of the simulation node is pressed no visualisation options appear in the VI Display Panel Instead grey scale fish eye images from the point of view of the Blender camera are created with coloured areas showing glare risk These images are saved in the project directory with the name glare frame_number hdr and also registered within Blender s image database and can therefore be viewed by opening up a Blender UV Image editor window LiVi also writes out the glare metrics calculated from the image on the right hand side of the image along with the data and time specified in the LiVi Basic node Dr Ryan
53. red then in the Blender material panel in Vi Suite Material tab there is an drop down menu called Material type Within this menu the option Calculate Shadow sensor should be selected An analysis will then plot on this sensing geometry a grey scale col ouration signifying how often that point receives dir ect sunlight when the sun is above the horizon for the specified simulation period The year period for the simulation is set within the Shadow Study node with the start month and end month options The period of each day to be simulated is set with the start hour and end hour options The Interval option sets the hourly time step for the simulation A value of 1 will do a calculation once per hour and a value of 0 25 will do one every 15 minutes The Animation option allows either a static analysis or one based on a geometry animation If Static is selected then results are valid for the current selected frame If Animated is selected results will be generated for each frame of the created animation Static EPW GBR_London Figure 32 Shadow Study node set up Dr Ryan Southall 24 School of Art Design Media VI Suite v0 3 In the 3D properties panel section 4 2 the VI Suite Display tab will present a shadow study display button and once this is pressed will also show options relevant to the shadow study The display panel options are shown in figure 33 The options in the display panel are o VI
54. rom https github com NREL EnergyPlus releases The default installation location should be chosen which the VI Suite assumes is in C EnergyPlusV8 4 0 Dr Ryan Southall 4 School of Art Design amp Media VI Suite v0 3 2 Installation From http arts brighton ac uk projects vi suite downloads download the VI Suite Python scripts zip file Inside the zip file is a folder called vi suite which should be moved to the C Users user name Application Data Blender Foundation Blender blender_version scripts addons folder created earlier As of Blender 2 76 Numpy is included within Blender s inbuilt Python installation Installing matplotlib for plotting capabilities is however a little complicated The best way appears to be to download a Python 3 4 environment like Anaconda and moving the required matplotlib components PySide dateutil six sip PyQt4 and pyparsing to the relevant folder in the blender folderV2 76Npython directory If matplotlib still does not work try typing import matplotlib pyplot as pit in Blender s Python command window Any error message should say which Python library is missing There is a bug in the interaction between Blender and matplotlib which causes Blender to crash if a png file is saved from a matplotlib window Save a pdf or svg file instead 2 3 Linux VI Suite has been tested on a 64bit Arch Linux installation First install Blender which is available though most Linux distributions package management sy
55. s within the wind rose node control the type of wind rose plot to create and the start and end months of the date range to plot Two types of histogram and three types of contour plot are avail able Examples of a histogram and contour plot are shown in figure 31 Once the button to create a wind rose is pressed a wind rose object is created at the centre of the scene This object like any Blender object can be moved scaled and re sized as desired Each time the wind rose button is pressed a new object is created When a wind rose object has been created one option will be exposed in the VI Suite Display tab section 4 2 of the 3D view properties panel Le gend This turns on the legend in the top left of the 3D view that relates wind rose colour to wind speed This legend will apply to the last wind rose object cre ated Figure 31 Histogram and contour wind roses EPW GBR_London Create Wind Rose Figure 30 Wind Rose node set up 5 3 Shadow Study The shadow study node also requires a VI Location node to provide latitude and longitude co ordinates so either an EPW file or manual entry can supply this data A typical node set up is shown in figure 32 A shadow study analysis requires sensing geo metry to be specified This geometry is specified via its material designation Once a Blender object has a material associated with it and this material can only be associated with specific faces of an ob ject if desi
56. stem Run Blender and select Save Startup File from the file menu to create a Blender configuration directory at home user name config blender blender_version where user name is your user name and blender_version is the Blender version number 2 76 at the time of writing Create within this directory a scripts folder and within this an addons folder The is available as a zip file from the VI Suite website at http arts brighton ac uk projects vi suite downloads Inside the zip file is a folder called vi suite This folder should be moved to the home user name config blender blender version scripts addons folder created earlier Download Radiance from https github com NREL Radiance releases or from the host package man agement system and install to the default folder The VI Suite assumes that Radiance is installed in the usr loc al radiance or usr share radiance folder A recent version of Radiance 5 0 or above is required Download and install EnergyPlus v8 4 from https github com NREL EnergyPlus releases The default installation location should be chosen which the VI Suite assumes is in usr local EnergyPlus 8 4 0 As of Blender version 2 76 Numpy is included with the Blender release but in general it is easier to install Python numpy matplotlib and the Python modules sip six dateutil pyparsing and PyQt4 via the distribution s package management system and removing the usr share blender 2 76 python folder to force Ble
57. surface nodes then specify the wind pressure coefficient values for these angles for particular surfaces 4 7 7 The EnVi WPC Array node The WPC Array node attaches to the EnVi Control node via the Control node s WPC Array socket node and specifies the angles of the wind from North that wind pressure coefficient values are specified for in the EnVi External nodes 4 7 8 The EnVi Schedule node Dr Ryan Southall 20 School of Art Design amp Media VI Suite v0 3 The EnVi Schedule node can be found in the Add Sched ule nodes menu in the EnVi Network node tree A sched ule node creates an EnergyPlus schedule which is used to control an inputs time dependence e g when windows are open All EnVi schedules basically operate over defined peri ods of a year for defined days within that period and defined hours of those days The node options reflect the spe cification of these three layers of time data The node is initially red and will only become the default colour when the options below are given valid values The options are 4 The Vi Suite Interface Figure 25 EnVi Surface flow node o End day 1 sets the end day of the first schedule s year period This defaults to 365 the last day of the year o Fors sets the day types valid day types are Alldays Weekdays Weekends Monday Tuesday Wednes day Thursday Friday Saturday Sunday and AllOtherDays for the above year period in a space separated list
58. tton A video showing activation and set up of the VI Suite can be found at http blogs brighton ac uk visuite 2015 10 22 vi suite v0 3 tutorial 1 activation Dr Ryan Southall 7 School of Art Design Media VI Suite v0 3 4 The Vi Suite Interface VI Suite Add node menu node trees Active node tree JE View Select Add Node Area select menu EnVi network Node tree node trees selector Figure 4 Blender node editor menus Blender nodes can be scripted with Blender s Python scripting back end and this allows some user feedback features to be implemented Nodes in general will be red if o The node contains a operator button which has not yet been pressed o The options selected within the node are different to the selected options when the operator button was last pressed o The options selected within the node are invalid within the context of the other nodes the node is con nected to The node colour will revert to the general Blender theme colour if none of the above conditions are true and the node in it s current state is valid as a simulation component Links between nodes are also scripted so that only valid links can be made If a link is attempted between two node sockets the link will immediately disappear if the connection is not valid Sockets are generally col oured to show which one can be connected red to red yellow to yellow etc In addition to the VI Suite nodes visualisation options when relevant beco
59. w 2 de go wd 27 5314 Photon Mapping III 28 529 RIVER 6 we che oe ewe ee EERE Ree oe eo ee Sas ars 29 Bo IMVLENSIST ANIOS x ddr ow RU ee oe eS SOS xu wd xo EAE CEES ES 31 5 5 1 EnVi construction specification 31 5 5 2 EnVigeometry conversion usu oe Ro X etiki eae a X Peed Eo 32 5 5 3 Storing EnVi custom constructions uuum os soo y sagas O9 ROO OA AR wx 32 554 EnVIZDDespecHICallON 2 2443 mc emo emo EORR Rmo Ro a Es 32 555 EnVinetwork creation uu 9 4 593 EGRE ROSE RS RS EHS E PS 33 5 5 6 BuVischedule specification uos usos 58 bak 399 33 3 3 93 x Sow ox Eo orem RED 33 B BASED IUE x23 945 9 93 43 5 99 A SS EN PASEOS AM PRESSES sw s 33 1 ADONG eME cse ox abe Cox ione io SERS mia oot TRO Red ox ERLE de y 34 Dr Ryan Southall 2 School of Art Design amp Media VI Suite v0 3 1 Introduction 1 Introduction The VI Suite is an open source add on to the 3D modelling and animation package Blender that provides a set of tools for the analysis of environmental factors within and around buildings It uses Blender s node system figure 1 to provide a user interface that allows quick and custom analyses to be created As of VI Suite version 0 3 nodes exist for GIS height map import sun path analysis wind rose display shadow studies lighting metric prediction thermal performance prediction and advanced airflow network creation The lighting and energy analyses are achieved with the two ma
60. w component between the two zones If only one socket is connected to an EnVi zone node the surface flow is as sumed to sit on the external boundary of the zone and control airflow between the zone and the outside air If Input is se lected for the WPC type in the EnVi Control network node an EnVi External node must then be connected to the other socket to represent outside conditions Options in this node include Figure 26 EnVi Surface flow node o Type the type of flow component effective leakage area ELA or crack o Subsequent options control the parameters of the selected component type Refer to the EnergyPlus input output reference file for further details Dr Ryan Southall 21 School of Art Design amp Media VI Suite v0 3 4 The Vi Suite Interface 4 7 10 The EnVi Sub surface Flow node The EnVi Sub surface Flow node creates a flow component within an opening building construction such as a window or door It contains two input sockets Node 1 and Node 2 and two output sockets Node 1 and Node 2 All of these sockets are for connection to the sub surface flow sockets of EnVi Zone nodes If a node socket on one side of the node is connected the similarly named socket on the other side of the node will dis appear This makes node connections within the node tree more flexible If both Node 1 socket and Node 2 socket are connected to two EnVi zones the subsurface flow is assumed to control airflow b
61. y ifa Heating limit has been set that limits capacity this maximum capacity value is set here o Thermostat level sets the thermostat temperature for the zone this thermostat set point can be sched uled by attaching a schedule see section 5 5 6 node to the HSchedule input socket These same options are presented for the cooling section with the thermostat cooling temperature schedule set by a schedule node connected to the CSchedule node The Outdoor air section allows the specification of how much of the incoming heating air is drawn from outside If Outdoor air is set none the heating air is purely recirculated The overall scheduling of the HVAC system can be set with a schedule node attached to the Schedule input socket The node also contains three schedule input sockets Schedule for setting the availability of the heating cooling system HSchedule for setting the heating thermostat schedule and CSchedule for setting the cooling thermostat schedule Dr Ryan Southall 18 School of Art Design amp Media VI Suite v0 3 4 The Vi Suite Interface 4 7 3 The EnVi Occupancy node The EnVi Occupancy node sets the level and timing of occupancy for the zone represented by the connected EnVi Zone node An example of such a connection is shown in figure 22 Figure 22 EnVi Occupancy specification The occupancy node contains options for the level of occupancy the metabolic rate work efficiency and clothing level
62. y period to be plotted o Chart type Line Scatter for line or scatter plots and bar for bar charts o Frequency Hourly daily monthly results plotting 4 4 Specific Analysis Nodes Analysis nodes can be found in the Add Analysis nodes menu in the VI Suite node tree Analysis nodes initiate actual calculations Some analysis nodes need to be part of a larger node set up for example LiVi and EnVi simulation nodes whereas others represent a complete analysis for example wind rose and shadow study nodes These standalone analysis nodes are described here 4 4 1 The Vi Wind Rose node The VI Wind Rose node takes wind data from an EPW weather file and creates a wind rose plot The VI Wind Rose node has one input Location in socket that connects to a VI location node Location out socket As EPW data is required EPW must be selected as a source of information in the VI Location node connected to the Location in socket Once a valid Location in socket connection has been made a drop down menu spe cifying the type of wind rose to plot two types of histogram and three types of contour plot are currently available two numer ical input fields to specify the start and end month for the wind rose data and one Export button are exposed Upon pressing the Export buttons a new wind rose object is created within the Blender scene which can be scaled moved or rotated as de sired Wind rose specific display options are also rev
63. ype CBDM Allows calculation of lighting and radiation exposure daylight availability useful daylight illumin ance and hourly radiation Lux levels options defines the lighting benchmark levels o Source options defines the type of climate data used to create the sky context o HDR Exports an HDR panorama of the sky If valid socket input connections have been made an Export button will appear at the bottom of the node Clicking this will export the context to Radiance format and stores it within the node 4 5 3 TheLiVi Simulation node The LiVi Simulation node figure 16 calls the rtrace compon ent of Radiance to calculate the chosen metric on the sensing geometry This node also shows the current range of frames for which a Radiance simulation will be conducted It has two in put sockets Context in which accepts connections from an other node s Context out socket and Geometry in for con nection to the Geometry out socket of a LiVi Geometry node Once valid socket connections have been made the node options are exposed The Accuracy menu controls the simula tion accuracy with more accurate values leading to longer simu lation times The options presented in this menu depend on the type of analysis being conducted a LiVi Basic analysis presents Low Medium High and Custom options LiVi Compli ance and CBDM analyses give rise to Initial Final and Cus tom options A Custom selecti

VI-Suite v0.3 Manual - University of Brighton Faculty of Arts

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