CFD Online Discussion Forums

CFD Online Discussion Forums (
-   FLUENT (
-   -   mass diffusivity (

saghir July 7, 2006 10:27

mass diffusivity

while running a FLUENT simulation i am getting the following message: warning check material properties : invalid (zero)diffusivity in each iteration. i use kinetic theory for mass diffusivity.

what would be the problem.

thanks in advance

Ryan July 10, 2006 13:19

Re: mass diffusivity
Hi Saghir,

I had that problem too. Read up on what kinetic theory actually does. Somehow the results of that are giving a result of zero for one of your materials. Try just guessing a value to see if the program runs that way...if it doesn't, then there's a different problem.

Cheers, Ryan

saghir July 17, 2006 07:01

Re: mass diffusivity
Hello,Thanks for your help the program runs that way with a constant value of diffusivity . I use kinetic theory method because I do not know a formula to calculate the humid air-water diffusivity.

All times are GMT -4. The time now is 13:22.