[TRNSYS-users] Problem with View-Factor Matrix and detailed radiation mode

Dear Trnsys-Users,

I try to model a double-skin facade on Trnsys, using Trnsys3d, the multiple nodes feature and Contam.

The double-skin facade is a 1.2-meter wide and 2.8-meter high zone that is split vertically in four 0.7-meter high zones separated by virtual surfaces that are not imported in TRNBuild. I have imported the SketchUp model into Trnbuild. I have moved the nodes of the double-skin façade into one single zone.

I have set the radiation modes to “detailed model” (for beam, diffuse and longwave radiation) only in zones where I want to perform detailed radiation calculation. So I think I’m all set to generate the view-factor matrix file but TRNBuild doesn’t calculate it: I don’t get any error when I click on Generate < Generate View-Factor Matrix but there is no matrices in the *.vfm file that is generated (only zones ID numbers and names, and a 0 below each line – see attached file: it looks like detailed radiation mode is not selected in any zone).

I use Trnsys 17.00.0019, Trnsys3d version 1.0.5.2 and TRNBuild 2.0.167.

I’m sure I’ve done something wrong but I can’t find my mistake in the user-guide or in the trnsys-users archives.

Does someone know how I could generate proper view-factor matrices?

I’m also facing the same problem with the shading matrix. I defined a shading group in Trnsys3d but it seems like TRNBuild ignore it when calculating the *.shm file: “No window is shaded. Therefore no shading matrix file *.SHM is written!” (even if I’m pretty sure several windows are shaded).

I tried to compare my *.bui file to the *.bui file in the 3D_Building example folder. I noticed that there is a missing part in my *.b17 file in the section _EXTENSION_BuildingGeometry _. Indeed the _EXTENSION_BuildingGeometry_END_ statement comes right after the description of the vertices. There is no part with description of vertices used by each wall of each zone like in the example file:

zone EG_GB

wall 1 1 2 3 4

wall 2 5 6 7 8

[…]

I also noticed that when I try to update the Trnsys3d file to go back in SketchUp, description of surfaces comes with description of zones only for virtual surfaces so that when I open the updated Trnsys3d file in SketchUp, only virtual surfaces are drawn.

I think these two comments might help solving the problem.

Any idea would help,

Thank you,

Damien.

Attached: *.idf, *_b17.idf, *.b17, *.vfm, *_shd.log, *_updated.idf