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Coupling Darcy's law with Navier-Stokes equation - convergence problem
Posted 2014年12月11日 GMT-5 17:02 Fluid & Heat Version 5.0, Version 5.2 3 Replies
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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
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
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3 Replies Last Post 2016年1月20日 GMT-5 01:37
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Posted:
10 years ago
Can you send your model to liruixjtu@163.com ?
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Posted:
9 years ago
Hello Maximillian
Have you found a solution to your problem?
Have you found a solution to your problem?
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Posted:
9 years ago
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