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blinds.xml has negative thickness

asked 2017-02-07 13:53:20 -0600

Determinant gravatar image

updated 2017-02-07 17:00:33 -0600

The default InteriorShade for OS Radiance, blinds.xml has a negative thickness when imported into WINDOW7.4. Should I be concerned about results in OS Radiance?

These blinds seem to have been generated very similarly to the procedure outlined here:

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answered 2017-02-07 16:44:02 -0600

updated 2017-02-07 16:50:48 -0600

I never import BSDF XMLs into WINDOW, but I did follow the guidance in that document you reference to create blinds.xml, and it was created for Radiance -- specifically, for the Radiance daylighting workflow in the Radiance measure.

So, no (you should not be concerned).

For sanity testing of BSDFs I recommend using BSDF Viewer or the bsdf2rad debugging tool to visualize the distributions. This tutorial includes some examples of using these tools, and this hilariously irreverent blog post summarizes the Radiance BSDFs in OpenStudio.

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Yes, I had looked and it looked good to me on BSDFViewer but wondered if maybe thickness played some weird behind-the-scenes role. Thanks for reassuring me of their validity. I'll probably email LBNL now and see if maybe they need to take a look at their end.

Determinant gravatar imageDeterminant ( 2017-02-08 19:59:35 -0600 )edit

Thickness is used in WINDOW for thermal calculations, so it should not affect Radiance modeling. However, if you want to calculate SHGC or U-factor in WINDOW, then you should edit xml file and put proper thickness.

curcija gravatar imagecurcija ( 2017-02-09 09:55:19 -0600 )edit

I don't need thermal calcs for what I'm doing so it seems I'm good. However, WINDOW seems to calculate thickness and not use the <thickness> tag in the XML. I tried that and WINDOW kept coming up with the same negative thickness.

Determinant gravatar imageDeterminant ( 2017-02-09 14:51:40 -0600 )edit

Thanks for pointing this out. Can you send the copy of XML file, so that we can look into this? Thanks.

curcija gravatar imagecurcija ( 2017-02-09 16:09:23 -0600 )edit

Where do I send it to?

Determinant gravatar imageDeterminant ( 2017-02-09 17:01:05 -0600 )edit

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Asked: 2017-02-07 13:53:20 -0600

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Last updated: Feb 07 '17