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Implicit scheme for incompressible flow problems

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Old   August 10, 2002, 11:00
Default Implicit scheme for incompressible flow problems
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Triton
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I'm solving incomprssible Navier-Stokes equations with artificial compressibilty method. In order to use large pesudo time step, I use implicit scheme to integral in time. The converged solution, where all the dq terms drop to machine zero, is found to be dependent on cfl number. Is this normal? If there are any problems, what could the problems be?
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Old   August 12, 2002, 22:59
Default Re: Implicit scheme for incompressible flow proble
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versi
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Solutions of some schemes such as Macormack, Strang type splitting, really dependent on time step. You will be required to give specific scheme used so that others can answer you.
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Old   August 16, 2002, 08:22
Default Re: Implicit scheme for incompressible flow proble
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j.p.rao pasupuleti
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Old   August 24, 2002, 09:45
Default Re: Implicit scheme for incompressible flow proble
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Andy Froncioni
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The answer is: when you have reduced the time step to the point where your solution no longer changes much, you will have properly modeled your system.

It is vitally important to make sure that your solutions are properly converged in time and in space.

Implicit schemes guarantee stability, not accuracy, in time.
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Old   August 25, 2002, 04:54
Default Re: Implicit scheme for incompressible flow proble
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roro
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what is the problem you are working for?

Maybe the problem is sensitive to disturbence.
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