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Implicit ddt and Courant Number

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Old   February 9, 2010, 13:17
Default Implicit ddt and Courant Number
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Aleksey Rukhlenko
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Hello, colleagues.
Please, help me with the following problem.
I'm solving transport equations (convection + diffusion) for some species using Euler implicit representation of time derivative term (fvm::ddt in solver code and Euler scheme fvSchemes). Such implicit scheme must be unconditionally stable. Why anything crashes if Courant number > 1? I mean iterative process in solving discretized equations diverges.
And please, tell me, is there in OpenFOAM of method to solve Navier-Stokes equations for laminar flow, which lets to set Courant number > 1?

Best regards, Aleksey.
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Old   February 12, 2010, 04:41
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Vojtech Betak
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Hi Aleksey,

try to use solver pimpleFoam. It's stable for Co > 1.

Vojta
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