Hi

I'm trying to model a porous fin in fluent. For free convection I need to investigate the effect of Darcy number on heat transfer. How can I relate the Da for example 10^-3 to the Porous zone in cell boundary condition part in fluent. There is formula for Darcy number " Da=K/(d)^2" that K is the permeability (m^2) and d  is the characteristic length.I'v read in another question that for 2D case the inertial resistance=0 and viscous resistance=1/K. Is that true ?? if it is what's the characteristic length for my case??

Regards.