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Old   April 8, 2010, 11:32
Default convergence limits
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Domenico
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Dear all,

I'm working to simulate a fan on CFX and after the numerical simulation I saw that the residual level doesn't go down below E-3, E-4. Then I want to know which parameter I can play on, in order to achieve a residual level around E-5, E-6.

Kind regards

Domenico di Cugno
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Old   April 8, 2010, 11:40
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Ciro Cannavacciuolo
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if you are simulating a steady run, you can reduce the timestep value.

if you are simulating a unsteady run, you have two possibilities:

a) reduce the dt

b) increase the number of the sub-iterations at every timestep
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Old   April 8, 2010, 18:13
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Glenn Horrocks
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Again, this question has been asked a million times - please refer to the FAQ

http://www.cfd-online.com/Wiki/Ansys...gence_criteria
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