hi:

I have a problem about the species transport I want to set the species to diffusion in a single direction ,

I try the porous zone,but it just can make the flow to flow in a single direction,it can not make the species to transfer in a single direction

thank you so much

chocheng

I don't think you can have a diffusion co-efficient which is different in different directions. As far as I'm aware all diffusion co-efficients are isotropic. You can't even set the user defined diffusion co-efficient to have different values in the different co-ordinate directions!

Greg