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Old   June 11, 2008, 15:10
Default Flat residuals?
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Ahmed
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Hi

I am simulating a steady state flow in a box. It is a compressible flow. I am using total pressure at the inlet = 101326 and static pressure at outlet = 101325.

My problem is that my residual become flat after 20 iterations and I do not observe any change in them. How can I achieve convergence in a such case? Thanks in advance for your help.

Ahmed
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Old   June 12, 2008, 10:01
Default Re: Flat residuals?
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Dr. V. Kumar
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1 Pa pressure difference seems to be too low to get the flow go through your domain.
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Old   June 12, 2008, 10:23
Default Re: Flat residuals?
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Ahmed
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Hi Kumar

Unfortunately, thats how things are. Is there a way to achieve convergence for this case.

The corresponding velocity for 1 Pa pressure is about 2 mm s^-1. It should make it to other side. Thank you
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Old   June 12, 2008, 18:30
Default Re: Flat residuals?
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Glenn Horrocks
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http://www.cfd-online.com/Wiki/Ansys...gence_criteria

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Old   June 13, 2008, 05:26
Default Re: Flat residuals?
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Ahmed
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Thank you Glenn. This is very helpful.

Ahmed
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