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Finding/calculating values for Site:GroundTemperature:BuildingSurface

asked 2015-07-21 08:33:31 -0500

FrontierAssoc104 gravatar image

updated 2015-07-23 13:00:33 -0500

I am using DOE Reference Building files (.idf), but modifying them with information from Representative City data from another state (Las Vegas -> El Paso). One part of replacing the weather data is the Site:GroundTemperature:BuildingSurface information. I cannot find this in the .stat, .epw, or .ddy files from El Paso. Is this a calculated value, and if so, how is it calculated?

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answered 2015-07-21 11:56:06 -0500

updated 2015-07-21 12:00:15 -0500

A quick answer from the documentation suggests using 2°C lower than the average internal temperature for commercial buildings in the US. Be aware that this is not appropriate for smaller buildings such as residential due to the dominance of edge effects.

The link above also points you to the Auxiliary Programs documentation about ground heat transfer, which introduces how to use the Slab program for calculating the correct values.

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I am having a little trouble with the Slab program. First, I can't find anywhere an example of the GroundHeatTransfer:Slab:Control object and what it should look like. I see in the input-output reference that it needs: Field:Name and Field:Run Slab Preprocessor, but I'm not sure what the format looks like. Additionally, I am wondering where the Slab objects and GroundHeatTransfer:Slab:Control object are positioned in the IDF file. Do they necessarily need to be placed in a specific place (before or after any object)?

FrontierAssoc104 gravatar image FrontierAssoc104  ( 2015-07-23 09:56:21 -0500 )edit

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Asked: 2015-07-21 08:33:31 -0500

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Last updated: Jul 21 '15