Question-and-Answer Resource for the Building Energy Modeling Community
 | 1 | initial version |
Here is a diagnosis of the issue. 2 things are happening:
You don't have a Ground temperature object, so it defaults to 18oC and your floor (face 0) has undesired heat conduction.
The really cold sky during february is making it have lots of heat loss, that's what offsets the ground heat transfer and it just "coincidentally" seems like your balance is almost steady state with no heat transfer, when it's actually 2 heat fluxes balancing out.
This can be seen in the surface heat trasnfer variable:
The ground temperature can be controlled with the ground temperature object, here is your .idf with a modification so the ground is at 25 in January and -5 in February: https://drive.google.com/file/d/1_AVOorIATuG4cdsMtUt2kffIWTFEGaa8/view?usp=drive_link
Your problem is that now no surface balances the roof and the zone temperature is lower than the outside air because of the way to cold sky, which I don't know how to manually modify nor do I know if it would simplify things so much that the study would be academically solid or not.
In any approach that you decide, I wish you luck in your simulations, PMP.
| | 2 | No.2 Revision |
Here is a diagnosis of the issue. 2 things are happening:
You don't have a Ground temperature object, so it defaults to 18oC and your floor (face 0) has undesired heat conduction.
The really cold sky during february is making it have lots of heat loss, that's what offsets the ground heat transfer and it just "coincidentally" seems like your balance is almost steady state with no heat transfer, when it's actually 2 heat fluxes balancing out.
This can be seen in the surface heat trasnfer transfer variable:
The ground temperature can be controlled with the ground temperature object, here is your .idf with a modification so the ground is at 25 in January and -5 in February: https://drive.google.com/file/d/1_AVOorIATuG4cdsMtUt2kffIWTFEGaa8/view?usp=drive_link
Your problem is that now no surface balances the roof and the zone temperature is lower than the outside air because of the way to cold sky, which I don't know how to manually modify nor do I know if it would simplify things so much that the study would be academically solid or not.
In any approach that you decide, I wish you luck in your simulations, PMP.
