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Strange spikes in my 2nd Order Solutions

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Old   April 21, 2009, 14:13
Default Strange spikes in my 2nd Order Solutions
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Daniel Harlacher
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Hi all,

I have trouble with the second order schemes for the convective part at high reynolds numbers.

I am running a 2D cylinder at Re 27400 with a RAS turbulence model (kE or RNG) and get a solution like the one shown in the picture I linked:



The coefficients are calculated with the common controlDict entries and the plot is made with a simple gnuplot command. As you can see the solution is "decorated" with random spikes(these can be huge ~100000).

I am using the "Gauss linear" for the convective term.

Anyone any ideas?
-harly
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Old   April 22, 2009, 11:51
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lin
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Hua Zen
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Hi,Daniel

I could not answer your question.I recently also do some numerical analysis of the cylinder flow at hight Re number.I remember once I have tried a case similiar to yours.2*10^5,but get a differenct result.Could you share the files?I would like to do a comparative analysis of this case.
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Old   April 22, 2009, 20:13
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Daniel Harlacher
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Sure,

it will take me a day or two, to come back to you, but just post your email address and I will send you the file.

- harly
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