thermal simulation of complex fenestration in energyplus

asked 2020-10-29 06:18:29 -0500

muin's avatar

updated 2020-10-29 13:20:10 -0500

i want to do energy simulation of a single room with a vacuum glazing using energyplus. the BSDF file of vacuum glazing is generated using LBNL window 7.7.10 software. after energyplus simulation when I check the envelope summary from HTML file, the U-value (5.288W/m2-K) of the glazing is much higher than the Window simulation result (2.38 W/m2-K). as a result, the energy consumption also higher even than a double clear IGU. could anyone please explain the reason? why the U-value of complex glazing is changed in energyplus simulation?

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Did you export the idf code from WINDOW? Are you just looking at glazing u-values, not considering frame? Are perhaps the u-values that are high without the air films? The results in WINDOW should be with air films.

Jean Marais's avatar Jean Marais  ( 2020-11-04 04:18:10 -0500 )edit

What do you mean by idf code? I have generated the idf file from window software to use it in energyplus. I compare the air-conditioning load of both double clear IGU and vacuum glazing unit. And it was found that air conditioning load is higher for VGU. Whereas, u-valu of VGU is lower than the IGU.

muin's avatar muin  ( 2020-11-04 05:27:53 -0500 )edit

What do your SHGCs look like? Check it in the Exterior Fenestration section of the html

Jean Marais's avatar Jean Marais  ( 2020-11-04 06:03:51 -0500 )edit

Heating energy? Cooling energy? Is your building with high internal gain? too many infos are missing to give you help

Ag's avatar Ag  ( 2020-12-14 16:36:54 -0500 )edit