[legendyxg]

Hi everyone. In my program, I need to add the following term into the source term of the UDS, i.e. source = ▽(D▽c), where c is a UDS in my case. Could anyone tell me how to write this term in UDF? I know we can get the gradient of a UDS through C_UDSI_G(c,t,i), but how to get the divergence of the gradient of a UDS?

Thanks very much.

[msaeedsadeghi]

You can store divergence of c into another UDS, then divergence of this new UDS. So easy.

[legendyxg]

Thank u very much Saeed!