FEAP User Forum

FEAP => FEAPpv => Topic started by: Michael on June 06, 2019, 07:32:38 AM

Title: Does FEAPpv simultaneously solve coupled pde systems?
Post by: Michael on June 06, 2019, 07:32:38 AM

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

Title: Re: Does FEAPpv simultaneously solve coupled pde systems?
Post by: Prof. S. Govindjee on June 06, 2019, 07:42:53 AM

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

Title: Re: Does FEAPpv simultaneously solve coupled pde systems?
Post by: Michael on June 06, 2019, 07:46:30 AM

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

Regards,
M

Title: Re: Does FEAPpv simultaneously solve coupled pde systems?
Post by: Prof. R.L. Taylor on June 06, 2019, 09:28:46 AM

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.