I have been solving a steady state internal electronicscooling problem using 2007 floworks 64 bit windows version.

Is there supposed to be a SOLAR radiation check box under generalsettings > radiation?

I ran a few analysis with radiation, environmental radiation on.Specified solar opening radiative surfaces, but the radiation fluxis always zero. The online manual says
" Select solar radiation check box to enable directional radiationfrom ambient space..." But I could not find the check box.

Also played with default wall radiative surface condition: Nonradiative and wall to ambient. Nothing moved the needle.

Thanks in advance for any help, tips and tricks.

SadatSolidworksFlow Simulation