[whiz]

Hi, all,
I am trying to program a UDF code to simulate the radiation heat transfer in porous media.
The recommended anisotropic phase function in porous media is:
f=8/(3PI)*(sin (theta) - theta * cos (theta) )

Can somebody tell me how to use this phase function in my UDF?
BTW, I am now using Rosseland model and P1 model.

In FLUENT, only the "linear anisotropic phase function" is supported, so if it is impossible to use the above recommended function, how to approximate this function to a "linear anisotropic phase function"? I mean how to decide the parameter C in the "linear anisotropic phase function" of P1 model in FLUENT software?

Thanks a lot!