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Help: MARS scheme does not converge!

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Old   August 7, 2007, 14:52
Default Help: MARS scheme does not converge!
  #1
Jimmy Fox
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Hi, I am using MARS differencing scheme for UVW-mom (with standard K-e, incompressible, hexa mesh) to simulate oil flows through a spool. The case seems not complicated, but it is difficult to converge. Any sugguestions about it?
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Old   August 7, 2007, 21:01
Default Re: Help: MARS scheme does not converge!
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Kevin
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Reduce the Blending Factor value to around 0.2. This will make it converge faster but still maintain a second order accuracy.

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Old   August 8, 2007, 01:59
Default Re: Help: MARS scheme does not converge!
  #3
matej
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and then try to move the blending back to see if you came to the same solution....
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Old   August 8, 2007, 04:16
Default Re: Help: MARS scheme does not converge!
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Jim
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Does it converge with UD?
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Old   August 8, 2007, 06:06
Default Re: Help: MARS scheme does not converge!
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murash-v
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I think you should try make Blending Factor value greater than 0.6. But it make more time! And try to use double presccision for solver. Does *info file contain any WARNINGS?
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Old   August 8, 2007, 10:06
Default Re: Help: MARS scheme does not converge!
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Jimmy Fox
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Thanks for your suggestion. I am trying the blending factor of 0.2 and will get results soon.
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Old   August 8, 2007, 10:08
Default Re: Help: MARS scheme does not converge!
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Jimmy Fox
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This case converges with UD (also double precision, without any wornings) very fast.
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