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April 12, 2005, 12:02 |
underrelaxation_factors??
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#1 |
Guest
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hello! please is there a way to understand when should we change the values of the default underelaxation factors in fluent, especially, concerning "species factors???"
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April 12, 2005, 15:21 |
Re: underrelaxation_factors??
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#2 |
Guest
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This is quite tricky and if you go through this forum and check earlier posts, you will definitely find some good pointers.
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April 14, 2005, 11:36 |
Re: underrelaxation_factors??
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#3 |
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Do you want to solve fpr species transport with or without reaction/s? -usually under-relax only when solution is unstable in initial iterations. -never under-relax heavily. under-relaxation of species should be at the max 0.8. -if you have to under-relax heavily, try: ---------check set-up of problem (most important). ---------try step-wise solution. ---------try coupled solver in that order. use coupled solver in case you have a high speed flow. default URFs usually need not be changed.
Regards, Swarup. |
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