Thank you for your feedback. Why this big case, because I was trying to study the increase of temperature of the solid body through hot gas entering through vent. But, even with 800°C hot air, I could only obtain 100°C on the surfaces of the solid. So, we wanted to check the convection for both 1D and 3D heat transfer model. Therefore, my professor wanted to check Conjugate Heat Transfer with a validation case. For this current case, we have results that can be compared to.
Initially, we could not apply boundary condition (like no slip) on the interface
that connects solid and fluid domain (since the split for parallel processors are aligned with the interface,. i.e., boundary condition on the connecting face of the mesh domain). This was not possible in FDS6. In FDS7, it works as far as i tested.
I understand that HT3D model cannot be placed on the exterior domain. Is it also not possible to place exactly at the abutting face of two mesh domains?