Does FEAPpv simultaneously solve coupled pde systems?

[Michael]

Hi there,

I want to know whether the FEAPpv could simultaneously solve the coupled nonlinear PDEs? I'm working on modeling the thermally induced moisture flow in the unsaturated soil. Currently, only pressure and temperature were considered. Please check the attached picture showing the coupled fluid and heat equations. This problem is a highly nonlinear problem because the coefficients are relating to each other.

Could the FEAPpv deal with it? Are there any other examples I could try and any suggestions are pretty welcome? Thank you very much!

Regards,
Michael

[Prof. S. Govindjee]

yes you can solve this type of problem in FEAPpv.  To do so you will need to write a user element.

[Michael]

Thank your replies Professor Govindjee. That's great! Could you show me some examples relevant to this type of problem?

Regards,
M

[Prof. R.L. Taylor]

If these are two scalar fields, you would assign \phi to dof=1 and T to dof=2.  Code the residuals and tangents -- it is just like any two dof problem (e.g., plane strain) except in your case you have two physics.  Both can use a backward Euler time integrator.