Inside surface temperature appear high and cannot explain


The simulation is a typical floor of a multi-storey office building in tropical climate. The air-conditioned rooms are at corners and sides of the square floor plan, and the center is a collaboration space without air-con. The collab space is connected to outdoors to allow natural ventilation.
I’m studying the thermal comfort of the collab space by HB adaptive comfort recipe.
I noticed the radiant temperature in the space is high, so I ran a full OS simulation and found out the inside surface temperatures are high. In particular, I can’t explain why the internal windows are so hot.
The room temperature looks ok. The collab is about 30degC, the AC space 1 is 24degC.

The inside surface temperature of the window between collab and AC space 1, for example, is above 32degC. I was expecting it to be between 24 and 30 degC.

Another thing I can’t explain is the difference between the AC 1 and AC 6:

Thank you.
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I have some guesses for what the cause could be, although my interpretation of exterior/interior and surface types of your model may be off since I’m going off the screenshots.

I think this is likely due to the reflected solar radiation from the exterior collab window, and maybe some long-wave radiation from the surrounding walls. One way to confirm this is to check the correlation between the exterior collab window and the interior AC space window temperatures (i.e. plot both of them over the course of a day and see how closely they match).

This likely follows partially from the first condition. If we assume the reflected solar is quite high, then AC 1 may actually be getting higher solar radiation relative to AC 6’s smaller exterior window. On top of that, AC 6 has a larger volume to surface ratio, which would play a large role in reducing peak temperatures relative to AC 1.