Honeybee AFN with Skylight

Hello all,

happy to see the LBT 1.3.0 has been released! I’m interested in the topic about how to simulate air flow network and convection heating transfer of big spaces in honeybee & energyplus. However, there are some problems when I design a model, which contains skylight in energy simulation with AFN. Please refer to the picture below.

I guess, that the roof or skylight aperture can’t be recognized correctly in AFN model, but I don’t know how to solve it. Is there any suggestions from your guys?
Skylight_AFN.gh (80.5 KB)

Ah, I was wondering when an issue like this might be discovered. I knew that the objects we were using for windows with the AFN weren’t made to model perfectly horizontal openings but I though that everything would be alright when the skylights weren’t operable like your model. I guess EnergyPlus is just particularly fussy when it comes to the AFN.

I think I probably get a fix for this case merged into the development version of the plugin today or tomorrow. I should clarify that the EnergyPlus AFN doesn’t currently support operable skylights that are perfectly horizontal since the math around this type of bi-directional flow gets really complex. But I should be able to get your model to simulate without issues since the horizontal skylights are not operable.

Thanks for your quick reply, Chris! Now I understand the temporarily inherent defects of AFN algorithm in Energyplus. However, although I turn off the “operable” option for skylight, the problem still exist.

Could you take few seconds and check it again? Thanks a lot in advance!

Did you miss this part of my response, @YZZhang ? I guess I should have said explicitly “this is a bug that I am going to fix.”

Ops, I might misunderstand your reply. Thanks for your patience!

@YZZhang ,

I just merged a fix into the development version of the plugin:

So your model with the AFN now succeeds.

I also added a check into the AFN component that will give you a warning whenever you have operable horizontal apertures on the exterior.

Leaving the skylights as in-operable ensures that everything is correct.

You can get the fixes on your end now with the “LB Versioner”.

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Thank you very much!