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How does EnergyPlus differentiate between inside and outside walls?

asked 2022-11-02 04:23:10 -0500

Tillski's avatar

updated 2022-11-02 20:39:20 -0500

Hey everyone, I'm pretty new to E+ so this might be a pretty basic question:

Can anyone explain to me, how EnergyPlus differentiates between inside and outside walls? For example if I want to simulate an office room that is part of a larger building, that has three inside walls and one wall facing outside (with an window).

As the temperature "on the other side of the wall" affects the wall temperature a lot and therefore also the temperature in the room I'm simulating I'm sure there is a way to include this.

Thanks a lot in advance!

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answered 2022-11-07 02:26:40 -0500

As Denis said, generally.

For your specific application, which is modeling one room as part of a larger building, the easiest is to put one wall as Outdoors and the 3 "inside" walls as Adiabatic. This will negate the heat transfer from these wall. This assumption is fine only if you think you have similar temperatures on both sides of the inside walls (eg: it's another office/room with the same thermostat setpoint on the other side).

If you have different conditions, you can use a SurfaceProperty:OtherSideCoefficients for example to set a specific temperature / temperature equation on the other side, but this is slightly more complicated.

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Hey Julien, hey Denis,

thanks a lot for your responses! That answers my question perfectly!

I think Outdoors and Adiabatic works great for my purpose.

All the best, Till

Tillski's avatar Tillski  ( 2022-11-09 05:07:27 -0500 )edit

Please remember to mark an answer as Accepted (green check mark below the up/down vote buttons) so the thread is marked as resolved. Thanks!

Julien Marrec's avatar Julien Marrec  ( 2022-11-16 20:00:44 -0500 )edit

answered 2022-11-04 13:56:15 -0500

Outside Boundary Condition field ("Outdoors" vs "Surface") of detailed Building:Surfaces.

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Asked: 2022-11-02 04:23:10 -0500

Seen: 178 times

Last updated: Nov 17 '22