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Converge issue on steady state pump

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Old   August 17, 2012, 11:32
Default Converge issue on steady state pump
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Elena Cortin
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I have a mesh of a pump that has Boundary layers on the parts : blade, hub, shroud. it has periodic walls and inlet/outlet.

The BL mesh has elements with aspect ratio of 20000 and a number of jacobian with 0.42 the smaller.

I try to run this pump on CFX and the solver can not converge at the timestep of 1/ω, I am using SST as turbolence model.

If i apply timestep at 1e-9 the solver converge but the results are really bad.

Do you think that might be the mesh that creates the issue? or i have to check something else?
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Old   August 18, 2012, 07:35
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Glenn Horrocks
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An aspect ratio of 20000 is pretty bad, even in a boundary layer mesh. I agree with you, I suspect you have inadequate mesh quality.
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