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Suitable for window shading simulation? Ecotect replacement needed!

asked 2019-03-26 05:30:17 -0500

anonymous user


I am totally new to Radiance and trying to figure out wether or not this can become our tool.

We use Ecotect for building simulation to get a shading percentage for each window for each minute throughout an entire year.

Ecotect has been retired, so we are looking for an alternative -- so far without success.

I understand that Radiance is a rather sophisticated tool, but nevertheless I would like to know if we could use it for the described purpose.

Thanks for any answers!

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answered 2019-05-31 11:45:38 -0500

Samuel de Vries's avatar

updated 2019-05-31 11:49:33 -0500

I would say that Radiance is too 'sophisticated' for what you want to achieve here. It has quite a steep learning curve. If I understand correctly you want to obtain the fraction of a window's surface area that is exposed to direct solar radiation.

Some tools/methods with which you can obtain this:

  • Ladybug (plug-in to Rhino/Grasshopper or Revit). The sunpath/sun expore components.
  • EnergyPlus. Request the 'Surface Outside Face Sunlit Fraction' output for a particular surface.
  • With Radiance this actually becomes a bit more complicated. I would recommend the two phase method (Daysim). You would have to setup a grid of points across the window. Measure Irradiance/illuminance and count fraction of points exposed. You either have to use a self defined illum/Irrad threshold above which you consider the point exposed to direct sunlight. Alternatively you could request only the direct radiation and count points > 0.
  • Climate consultant can also give you some idea of shading by obstructions and shading elements. Not as an exact fraction of for each minute though. The input is extremely easy though.
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Asked: 2019-03-26 05:30:17 -0500

Seen: 236 times

Last updated: May 31 '19