Solar radiation model

Min

Experts,

STAR-CD solar radiation model, I'm tired of a solar radiation model setting in STAR-CD. Please help me... First of all, there is no a detail explanation about it in STAR-CD manual. I'd like to caculate temperature distribution when solar shines on a solid surface. Can I get a reasonable result if I make a mesh set just by solid without fluid mesh? Ithink my result just with solid mesh isn't good because (-) temperature show in it. Initial temperature of all domain is 20 C.

Is a special setting need for solar radiation? Is there someting I missed in a setting? Or... Is it impossible to caculate solar radiation which solid model heat up by solar and the heat will conduct to beside solid...

Thank you in advance