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Coupling Darcy's law with Navier-Stokes equation - convergence problem

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Dear Comsol-Community,

in the hope that someone of this great community might help me, I will try to explain my current problems with coupling Darcy's law and laminar flow. Basically I want to study the flow between an air-hockey table and a levitating glider. The flow in the porous air-hockey table is assumed to satisfy Darcy's law, while the laminar flow in the gap between the air-hockey table and the levitating disk is described by the Navier-Stokes equation. Both on the inlet and the outlet the pressure is described. So much for theory.
I have worked through the Darcy-Brinkmann-NS tutorial and tried to do the same in 3D. So far I'm able to couple Darcy and NS in twodimensional problems, but as soon as I try to do the same in 3D it doesn't work. In order to figure out the root of the problem I have created a simplified model. However no matter what I do it won't work. The nonlinear iterations take much more time than in 2D and the solver fails to get any solution. I have changed settings, solver, mesh, boundary conditions without any success. What am I doing wrong. I suppose there is something wrong with the coupling between Darcy and NS, but I can't figure out the problem.
For those of you, who are interested I have attached the simplified model. Please have a look at it and see what I mean. Any advices how to achieve convergence and improve convergence speed are greatly appreciated.

Thank you in advance.
Best regards,
Maximilian


3 Replies Last Post 2016年1月20日 GMT-5 01:37

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Posted: 10 years ago 2014年12月12日 GMT-5 08:56
Can you send your model to liruixjtu@163.com ?
Can you send your model to liruixjtu@163.com ?

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Posted: 9 years ago 2015年10月28日 GMT-4 03:03
Hello Maximillian

Have you found a solution to your problem?
Hello Maximillian Have you found a solution to your problem?

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Posted: 9 years ago 2016年1月20日 GMT-5 01:37
hi my dear . now i am facing the similar problem . so i sincerely know how you dealt with your questions .thank you best wishes to you
hi my dear . now i am facing the similar problem . so i sincerely know how you dealt with your questions .thank you best wishes to you

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