Question-and-Answer Resource for the Building Energy Modeling Community
Get started with the Help page
Ask Your Question

adiabatic as an outside boundary condition

asked 2016-04-19 13:01:08 -0600

updated 2016-04-19 13:01:56 -0600

I know this is a basic question but I am really curious to know when outside boundary condition of a surface is adiabatic? what does it mean? Thanks in advance for any answer.

edit retag flag offensive close merge delete

1 Answer

Sort by ยป oldest newest most voted

answered 2016-04-19 13:06:17 -0600

updated 2016-04-19 13:07:26 -0600

It means that no heat transfer will occur for this surface, at ALL.

It won't lose or gain any heat to the outside, will not receive any solar gains.

Case where you could use this is it you are modeling only part of a building for example. If you are not modeling an adjacent zone, then you would set the surface as being adiabatic.

Note that the thermal mass of this surface will still be taken into account.

edit flag offensive delete link more


Thanks Julien, May I know that adiabatic wall could have window?

4Designer's avatar 4Designer  ( 2016-04-19 13:30:12 -0600 )edit

You can't have any windows in a base surface with an adiabatic boundary condition. If you do, the windows will be removed prior to simulation. If you have a specific use case where you need that, you can mimic the adiabatic condition by making a super insulated wall that is nearly perfect.

David Goldwasser's avatar David Goldwasser  ( 2016-04-19 14:27:17 -0600 )edit

@David Goldwasser, Thanks for your informative response.

4Designer's avatar 4Designer  ( 2016-04-20 00:53:11 -0600 )edit

@David Goldwasser, I am using the measure Set Exterior Walls and Floors to Adiabatic1. I just want to confirm that the only difference between this measure and Set Exterior Walls and Floors to Adiabatic is the inclusion and exclusion list for the surfaces.

sashadf1's avatar sashadf1  ( 2021-04-06 10:18:46 -0600 )edit

@sashadfi, I assume you are using an old copy of the Set Exterior Walls and Floors to Adiabatic measures?

This measure has a bool to include walls for each cardinal direction, and also has bools for Roof, exterior exposed flors, and ground exposed floors. In addition to those bools, there is a string argument for inclusion list, and another string argument for exclusion list. This allows you to customize behavior for specific surfaces and models.

David Goldwasser's avatar David Goldwasser  ( 2021-04-06 14:15:50 -0600 )edit

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer


Question Tools


Asked: 2016-04-19 13:01:08 -0600

Seen: 1,030 times

Last updated: Apr 19 '16