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Old   August 25, 2003, 23:41
Default Help!!!
  #1
Miko
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Hi all! If the momentum source added in subdomain is very sensible to the velocity, such as the momentum is equal to "c*velocity", and the coefficient "c" is quite large, what should do to set to make CFX solver to converge?
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Old   August 27, 2003, 15:23
Default Re: Help!!!
  #2
Robin
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Miko,

Add a momentum source coefficient equal to "c", the solver will use this to linearize the equations. Also, if 'c' is positive, the solver will blow up on you. When multiplying by velocity, you should only use negative (resistive) coefficients.

Regards, Robin
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Old   August 27, 2003, 20:44
Default Re: Help!!!
  #3
Miko
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Dear Robin,

Thank you very much! You are really a good people! I think my problem can't be solved by setting a linear resistibility, for the momemtum sources at different direction are different. For instance, x-component is 0, but y-component and z-component are both c*velocity. So how to deal with it?

Best regards!

Miko
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Old   August 28, 2003, 15:42
Default Re: Help!!!
  #4
Robin
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There is only one entry for the source coefficient, use whichever c is largest.

Robin
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Old   August 29, 2003, 03:00
Default Re: Help!!!
  #5
Miko
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Hi Robin,

I think I can try! Thank you!

Best regards!

Miko
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