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Choosing the right timestep

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Old   October 28, 2009, 08:52
Post Choosing the right timestep
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Dennis Rown
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Hello!

I simulate with sonicFoam a tube with different pressures in it and have problems with the timestep. Sometimes with a chosen timestep, simulation lasts about 1 hour before it fails (and the Courand number is over 1). Is there a way to determine, how large the Courand number will get or is there even a possibility to set the maximum Courand number, so that the timestep will vary?
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Old   October 28, 2009, 12:21
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Anton Kidess
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Yes, there is a possibility to specify a maximum Courant number. See how it's implemented in the interFoam solver (http://www.opencfd.co.uk/openfoam/doc/damBreak.html), or also threads in the forum (e.g. Problems with adjustable timestep control and maxCo Number).
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Old   October 29, 2009, 03:58
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Thanks a lot! Like in the post of your link, I also has to add some #include statements into the solver I used (sonicFoam). Now it works great!
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