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Few cells with high Courant

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Old   February 26, 2017, 13:32
Default Few cells with high Courant
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Hi,

during the computation I've found that one or two cells produces a very high Courant number in comparison with the neighbour cells. It may be 100 or even more times higher.

So the question is: does anybody know what to do with such cells or how this problem can be overcame ?

Thanks
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Old   February 26, 2017, 14:28
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You have the highest Co numbers at regions with a high velocity of the fluid through small cells. If this region is not of special interest for you: Make them larger. If it the area you are interested it: Accept the Co number and its implications.
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Die der Hauptbewegung überlagerte Schwankungsbewegung ist in ihren Einzelheiten so hoffnungslos kompliziert, daß ihre theoretische Berechnung aussichtslos erscheint. (Hermann Schlichting, 1950)
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Old   February 26, 2017, 14:41
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It is clear.

But the problem is that I have a small cells before/after/around the problematic cells but Courant is the neighbouring cells is much less the in these particular 2-3 cells
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Old   February 27, 2017, 00:13
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May you post a graphic or at least sketch of your problem / mesh?
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