@Eero, I think this might be showing the thermal storage of the wall. That would explain the ‘reversed’ thermal profile. Adiabatic walls aren’t actually zero-flux barriers. In the EP engine the outside surface of the adiabatic surface is defined by the same surface, but mirrored. The mirroring is what creates, in net, zero heat transmission (as there is no temperature difference at the line of symmetry to result in heat transfer). This allows the adiabatic surface to model the thermal mass effects of the construction.
That being said, I’m not sure if the Surface Energy Gain/Loss result metric tracks this phenomena.
A couple of things to check to verify this:
- The cumulative sum of the heat gain/loss for that surface should be approximately zero after a yearly simulation (gain/loss should cancel out).
- Changing the specific heat capacity of the adiabatic surface should result in higher absorption/release.
Maybe try that?
Also what’s the (normalized) magnitude of the energy gains/losses for one of your non-adiabatic surface, with this one?