Workshop 03: SquareOne Ecotect

back to Digital Detailing: Fall 2007

Ecotect Workshop

We will use ECOTECT to quickly and easily visualize a variety of environmental data. Its graphical approach is more suited to basic testing and early design development - rather than a validation strategy for finished buildings.
From the SquareOne website: ECOTECT is the most user friendly and fully featured building performance analysis and design tool on the market today. It combines an interactive building design interface and 3D modeller with a wide range of environmental analysis tools for a detailed assessment of solar, thermal, lighting, shadows & shading design, energy & building regulations, acoustics, air flow, cost & resource performance of buildings at any scale. ...and even more importantly, it has been written and developed by designers for designers, to be as useful at concept stage as it is during final design development.
Download the demo here: Ecotect Trial

Importing NYC weather data into Ecotect. This includes temperature, prevailing winds and rainfall data

Solar Exposure

It can do solar exposure and shading studies. Here are the steps:

• Establish Geometry
• Import weather data file...
  • Under Model select Date/Time/Location
  • Click load climate data and select new york new york
  • Allow ecotect to change the global position to match climate file
• Go to Calculate and click Sun Path Diagram
• Select a surface from your geometry. All data displayed will be relevant to this surface. You should notice that certain parts of the graph are shadowed.
• Select Calculate Shading... and make sure Overshadowing Percentage is selected under Displayed data and press OK
• For help on understanding stereographic projection in ecotect see this site: http://squ1.org/wiki/Sun-Path_Diagram
• For help on understanding shadowing diagrams in ecotect see this site: http://squ1.org/wiki/Sun-Path/Overshadowing

Adjusting the analysis grid to our object extents

Lighting Analysis

It can do lighting analysis. Here are the steps:

• Establish geometry
• To fit the analysis grid to your geometry...
  • Select all of your geometry
  • Under the analysis grid tab, select fit to selected objects and fit grid extents in all axis - you should see your analysis grid (if its turned on) fitted to the extents of your geometry. It should only display a 2-dimensional representation.
• To adjust analysis grid density...
  • the density of your analysis grid will determine both the fineness and accuracy of your simulation.
  • select grid management under the analysis grid tab...
  • under management type in the number of cells for each axis (x,y and z)

Running an outdoor lighting analysis at medium quality

• Run caculation with proper settings
  • Now that we have setup the grid properly, we can run the simulation. At the bottom of the tab, make sure lighting levels is toggled and click perform calculation
  • In the dialogue box that opens up, select Full-daylighting Analysis under Calculation settings and make sure Full 3D Grid Calculation is toggled. You may want to set the precision to low or medium to allow the calculation to run faster.
• To re-adjust the analysis range...
  • Change Minimum under Grid data & scale to 0 and Maximum to 100
• To adjust the sectional view of the analysis grid...
  • See Grid Data & Scale... and adjust the offset
  • Note that you can adjust the section plane by changing the axis

Readjusting the display range for our analysis

• To adjust how our data is displayed...
  • See the Grid Settings at the top of the tab and try toggling the Show values in 3D or Show contour lines

Acoustic Analysis

It can do acoustic analysis. Here is some interesting reading on the characteristics of sound and how we perceive sound in our environment, as well as a guide to decibels - link. Here are the steps to setting up an acoustic simulation:

• Establish interior model. Acoustic simulation assumes an interior condition. If youre speaker object is not contained within some geometric volume, it will not cast rays in a uniform fashion.
• To create a speaker object...
  • In the Draw menu select Sound Source
  • Place your speaker object in the XY plane with the first click. To have it face upward, keep your mouse on the same spot, hold down the CTRL key and move your mouse, then click.
  • To change the volume of the speaker, select the speaker and go to the Material Assignments tab to the right, and double click the speaker object that shows up in the tab. Change the Sound Level(dB) to the desired number in the model view properties tab, and press Apply Changes

Changing the animation step for an acoustic particle simulation

• To setup a ray calculation...
  • Go to the particles tab to the far right. Under Generate Rays select Spherical random and max out the azimuth and altitude.
  • Select Generate Rays
  • Depending on how many rays you have allowed for and how many bounces, you will wait either a short or long time for ecotect to perform the simulation. More than 10 bounces is probably unnecessary and more than 10000 rays is probably excessive.
• Under display settings, change to Animated particles - you can now use the animation menu to stop and start the animation.
  • You might want to adjust the time-step of the animation. Do this by typing a smaller number in the frame step increment box.

Prevailing wind diagram in ecotect

Prevailing Wind Diagrams

It can show prevailing wind data and other weather metrics. Here are the steps:

• Import weather data file...
  • Under Model select Date/Time/Location
  • Click load climate data and select new york new york
  • Allow ecotect to change the global position to match climate file
• To show prevailing wind diagrams for the given location...
  • Go to the Calculate menu and select Prevailing Winds
  • Select a desired time period (optional) and make sure Display data is set to Wind Frequency (note that it is also possible to display other weather data, including temperature, humidity and rainfall) - press OK

Creating an emitter from our line object

CFD in Maya

CFD, or Computational Fluid Dynamics, is a rapidly evolving science. At present, Ecotect does not properly integrate with existing CFD tools, which are mostly command-line 3rd party programs developed by research institutes. Maya gives us the best access in terms of a usable GUI as well as easy geometry setup. For our purposes (both visualization and working) 2D fluid simulation to create a wind-tunnel effect will be most helpful. Find an example file here (Right click and Save link as...)

Modeling the Simulation

Setting up the geometry and particle emitters/containers.

• To create a fluid container...
  • Under the Dynamics workspace, in the Fluid Effects menu select Create 2D Container
• Draw a line & make it emit
  • Switch to the front view by accessing the menu directly above your viewport... View... Pre-defined bookmarks... front
  • Draw a 1-degree curve by going to the create menu, and selecting the options box next to EP Curve Tool - make sure 1 degree is selected, then click in your viewport (holding shift to make a straight line on the second click)
  • Select the line, add the fluid container to the selection (shift-click), and goto the Fluid Effects menu... Add/Edit Contents... Emit from Object

Setting the fluid boundary to be permeable to achieve a wind tunnel effect

• To add objects to the simulation...
  • In the Create menu... Polygon Primitives... Cube
  • Use the mouse to draw the extents of your polycube.
  • Select your polyCube, add the fluid container to the selection (shift-select) and goto the Fluid Effects menu... Make Collide

Visualization and Accuracy

Now that our simulation objects + geometry are setup, we can focus on both the fidelity and the appearance of the output.

• To allow air to escape the container...
  • Select your fluid shape and go to the attribute editor (ctrl-a) - At the top of the editor under the Container Properties, see Boundary X and change the options box from Both Sides to None - do this for Boundary Y as well.

Displaying CFD simulation vector data

• To change the fineness of the simulation...
  • Again in the attribute editor of the fluid shape, increase the Resolution from 40 x 40 to 60 x 60 (note this will slow down the simulation as it will increase the number of calculation drastically)
• To see the raw vector information...
  • Again in the attribute editor of the fluid shape, go down to the Display options and toggle on velocity draw
• To extract the vector information as a series of lines...
  • Copy the contents of this script (highlight and ctrl-c) Extract Vectors from Fluid
  • Open the script editor by clicking the lower-right-most button in Maya
  • Paste the script into the script editor, highlight it and press ctrl-enter with the fluid shape selected. It should prompt you for a scale. Try .25 first - if your lines are too long, decrease. Too short, increase.

tutorial posted by --Proxyarch 13:12, 15 October 2007 (MST)