Thermal Map question -- non-convex srf and schedule

Hi, everyone, I'm quite new to HB and I was trying to get a thermal comfort map following Chris's code, But there are two main questions.

A. The E+ simulation get a warning: there are non-convex srf. I have modeled all zones as cubes and not sure why it is still considered as non-convex. I have looked through several posts and it seems like this error will effect the surface temperature simulation which would be not accurate for thermal comfort. But I don't know how to find those surfaces and rebuild the model (some posts mentioned to split the non-convex zone, anyone can give an example about how to do that?)

B.After hours not figuring out the previous problem, I was thinking about running the thermal map to see how serious the error would effect. And there's come another problem. I set a summer day and Before sunset the result seems reasonable, however after 6 pm, the indoor temperature keeps over 38 C ( I used weather file of San Antonio). It seems like my cooling system doesn't work. And I have no clue how to check them out.

Thanks.

Qinheng

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Permalink Reply by Qinheng on March 18, 2016 at 7:33pm

And another attachment about the thermal result, after 6pm it's super hot.

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heatingcoolingSystem.PNG, 39 KB

Permalink Reply by Mostapha Sadeghipour Roudsari on March 19, 2016 at 7:59am

A. Wall surfaces after the split are non-convex. You need to split them more to create convex surfaces.

Permalink Reply by Abraham Yezioro on March 19, 2016 at 9:45am

If you see you floors/ceilings you can see that they are convex. If you want to get rid of this warning you should split also the floors.

-A.

Permalink Reply by Chris Mackey on March 19, 2016 at 2:59pm

Qinheng,

The thermal map is a really detailed, time-consuming analysis that you usually don't want to dive into until you have already understood/debugged your energy model on a coarse zone-by-zone level. I would really recommend watching the full youtube tutorial series on the EnergyPlus workflow before jumping to the thermal maps:

https://www.youtube.com/playlist?list=PLruLh1AdY-SgW4uDtNSMLeiUmA8Y...

The series will also show you how to set up your geometry as multi-zone with air walls, which you will have to do in order to get the "non-convex" error to go away.

Hope this helps,

-Chris

Permalink Reply by Qinheng on March 20, 2016 at 3:27pm

Hello, Chris,

I have watched through the series before, thank you again for this amazing tutorial. After Mostapha's advise the non-convex error has solved. I think now I need to dig deeper about the shcedule and load.

Thanks for your help

-Qinheng

Permalink Reply by Qinheng on March 19, 2016 at 4:18pm

Hi, Mostapha.

Thanks a lot. After split all these surfaces the simulation works fine. And for the second question, when I turned on the 'Ideal air load system' at create HB zone component, the result became reasonable, so I think I might have missed some settings when I turned it off and set my own HVAC system. Do you or anyone else would be so kind to share an example file or advises about how to set up one's own HVAC system (or is that feasible)? Or should I just use the ideal air system and use the set HBzone load and schedule components to customize it?

Thank you!

-Qinheng

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