Species Transport Model

Sam

Hi I had a question: When solving for species transport model: I allow the flow field to converge and after the converged flow field is obtained i turn on the species transport option.

I had one confusion : When i turn off the flow equation in Solve-control Panel Does it solve pure diffusion problem or does it take average velocity from the converged flow field. I mean to say by turning off flow Does it solve 1. { del C/del t + D grad 2 C = 0 } equation. Or does it solve 2. { del C/del t +mu * grad C + D grad 2 C = 0 }

Would be great if you could help me solve my confusion.

Bye