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Error extending number of surfaces in ComfortViewFactorAngles

asked 2021-03-03 07:14:57 -0600

rafael.alonso gravatar image

updated 2021-04-02 12:37:10 -0600

Hi all,

I am trying to get the Radiant temperature calculation for a specific point in a zone, for which I am using the Angle Factor MRT option, as described here.

I have created a ComfortViewFactorAngles object, which is linked in the object for People, and input there all my zone surface names and view angles (around 40 pairs). I do this with the text editor.

At first, I couldn´t open the .idf in the idf editor, for which I have amended the Energy+.idd file, to extend the number of allowed fields in the object ComfortViewFactorAngles. It works well now.

The problem comes when I run the simulation, as E+ doesn´t accept this longer list of objects, and reports:

Program Version,EnergyPlus, Version 9.0.1-bb7ca4f0da, YMD=2021.03.03 12:50,
   ** Severe  ** Line: 19334 Index: 1 - Error parsing "ComfortViewFactorAngles". Error in following line.
   ** Severe  ** ~~~ B1WGPartywall26,

The object B1WGPartywall26 is the first surface name after the original number of names in ComfortViewFactorAngles. So it seems E+ does not understand that there are more surface and view angle names than the default.

I have traced this back to the Energy+.schema.epJSON file (I´m not sure if this is the reference file for E+ object structure) and ComfortViewFactorAngles doesn´t seem to be an extensible object there. However, I don´t know if this is the right place to fix it, nor how to do it.

How can I solve this limitation, and have E+ accept more than the default number of surface names and angles for the ComfortViewFactorAngles calculation?

If it helps, the IDD file I´m using is here.

Thanks in advance, Rafael

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answered 2021-03-04 09:21:35 -0600

As of EnergyPlus v8.9, neither the IDD nor the schema file (schema.epJSON) are read at runtime by EnergyPlus. Rather, the schema is embedded into the EnergyPlus binary so you cannot modify either file and expect an effect. Your only option in the near term would be to recompile EnergyPlus from source code. You could also create a GitHub issue requesting that the number of allowed fields in the ComfortViewFactorAngles object be increased for a future EnergyPlus release.

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thanks for the tip, but I´m not sure I would be able to compile E+ myself. I´ll add the request in Github for the future in any case. I´m wondering, has this changed for E+ 9.4?

rafael.alonso gravatar image rafael.alonso  ( 2021-03-04 09:40:22 -0600 )edit

The schema is still embedded into EnergyPlus for v9.4, if that's what you're asking.

shorowit gravatar image shorowit  ( 2021-03-04 09:47:21 -0600 )edit

Ok, that doesnt help either

rafael.alonso gravatar image rafael.alonso  ( 2021-03-04 09:49:42 -0600 )edit

The only other possibility is to simplify your model so that you don't need to extend the number of fields.

shorowit gravatar image shorowit  ( 2021-03-04 10:03:24 -0600 )edit

I think I´ll need to go down this route. It is still strange that this feature is limited to 20 surfaces (or so). Thanks!

rafael.alonso gravatar image rafael.alonso  ( 2021-03-04 10:23:00 -0600 )edit

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Asked: 2021-03-03 07:14:57 -0600

Seen: 54 times

Last updated: Mar 04 '21