Boundary condition film coefficient

[Mike Sealander]

I just installed 7.4 and started using it.

I created a very simple opaque wall assembly and applied boundary conditions to the inside and outside parallel surfaces. I used the Interior boundary condition for one surface, and got this error: "You need to have at least two non-adiabatic boundary conditions to do a simulation. Check your boundary condition definitions."

It turns out the Interior boundary condition in the library ships with a film coefficient set to zero. If I change the film coefficient (to .25, for instance), I don't get the error message and the program will proceed.

Should all boundary conditions have a non-zero film coefficient?

[Fabrizio Prato]

Hi Mike.
The answer is: yes, all non-adiabatic BC must have non zero film coefficients.
Fabrizio