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

Revision history [back]

click to hide/show revision 1
initial version

Window heat transfer

Hello all,

I already looked at previous questions but I still can not find an answer:

For a simple energy plus model, a room with one southside two pane glass window ( no frame, no divider, etc...)just glass:

(Surface Window Heat Loss Energy) is not equal to (Window Inside Face Net Surface Thermal Radiation Heat Gain Energy) and (Window Inside Face Convection Heat Gain Energy).

The calculation is for 1 am, so there is no solar radiation. There is no light and internal heat, so heat loss through inside window face should be only by convection and radiation. The difference is small but I wonder what cause this difference.

(Surface Window Heat Loss Energy) is a little higher than the sum of (Window Inside Face Net Surface Thermal Radiation Heat Gain Energy) and (Window Inside Face Convection Heat Gain Energy). This is also the same for single glass window, Why?

Thank you,

Window heat transfer

Hello all,

I already looked at previous questions but I still can not find an answer:

For a simple energy plus model, a room with one southside two pane glass window ( no frame, no divider, etc...)just glass:

(Surface Window Heat Loss Energy) is not equal to (Window Inside Face Net Surface Thermal Radiation Heat Gain Energy) and (Window Inside Face Convection Heat Gain Energy).

The calculation is for 1 am, so there is no solar radiation. There is no light and internal heat, so heat loss through inside window face should be only by convection and radiation. The difference is small but I wonder what cause this difference.

(Surface Window Heat Loss Energy) is a little higher than the sum of (Window Inside Face Net Surface Thermal Radiation Heat Gain Energy) and (Window Inside Face Convection Heat Gain Energy). This is also the same for single glass window, Why?

Thank you,