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Residuals not dropping in simpleFOAM.

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Old   April 26, 2018, 02:48
Default Residuals not dropping in simpleFOAM.
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Manideep Reddy
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Dear Foamers,

I am trying to simulate external flow over a geometry of an airship using simpleFoam solver and found that the residuals are not dropping at all after few iterations. So, I stopped the solver to see the pressure field. I found that the flow is not symmetric and pressure drag is more than five time that expected. Can anyone please explain why is this happening..?
Is this because I am using steady state solver for flows with unsteady phenomenon involved or other reason.

Thanks in advance.


TThanks in advance.
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Old   April 26, 2018, 03:09
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Uwe Pilz
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Depending on your Re number you may get an oscillatory solution. I recommend to use a transient solver like pimple- or pisoFoam. You see more directly where the problems of your models are.
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