Modelling a solar simulator in Fluent

Ben

Hi

Does anybody has some experience with modelling natural day lighting (or a solar simulator) in Fluent? I'm studying the air flow around external solar shading systems (2D simulations - infinite facade)

My approach is the following one: I simulate the solar irradiance as an external beam through a semi-transparent medium. This is possible because I'm using the Discretes Ordinates model. But then the difficulties start: I think all radiation is transmitted diffusively, because changeing the beam direction (X,Y,Z) doesn't alter the result. If I reduce the diffuse ratio to zero (I guessed this would transmit all radiation specularly), no radiation is heating up my glass facade and shading systems.

Does anybody has any suggestions on how to simulate solar lighting or a short-wave radiation source in Fluent ?

Thanks for helping me out. Ben