Source terms for additional variable transport eqn
 

Dear Friends, I am simulating the flow of liquid crsytals using a continuum model. I am solving multiphase particle model Fluid + Surfactant. I defined 3 additional variables Nx, Ny and Wstar. I am solving transport equations for these additional variables with appropriate source terms. My problem is the following:

For source terms of the transport eqn of additonal variables, I'm using user fortran CEL. These source terms contain the velocity gradient in surfactant phase and gradients of additional variables in surfactant phase.

When I use USER_GETVAR for obtaining either velocity field or additional variables. The solver terminates with error. I am also unable to use User Fortran for extremely simplified cases like assigning a constant term as source(I did that to check if user fortran works for the source terms of transport eqn of addtional variables).

And to my surprise, user fortran didn't work there.

Has anyone faced similar problem??? I'll appreciate any help in this regard. with regards, Nandini Rohilla.