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convergence in 10 minutes

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Old   March 22, 2017, 05:56
Default convergence in 10 minutes
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sarath
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hi all,
I am a beginer in Ansys, but i have managed to learn bladegen and turbogrid partly. I have created a geometry {heart pump}. The turbogrid shows low error % for the mesh, but on when i tried to check on fluent, the orthogonal quality was only 0.35. The steady statesimulations when run on CFX turbo mode convereged at 100 iterations which took only 10 minutes or so. The mesh has approx 280000 elements. The results are comparable to the ones i need. But the run time confuses me. please suggest the possible reasons behind the short run time. And how can i be sure about the mesh quality, because turbogrid tutorial claims low error statics requirement.

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Old   March 22, 2017, 06:45
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Glenn Horrocks
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The run time is short because CFX is an effective and efficient CFD solver. Or are you suggesting the run time is too short? If so, what makes you think that?

To check if your mesh quality is a problem, then do another mesh with either a much better or a much worse mesh. Redo the simulation and see if it affects the results.
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Old   May 22, 2017, 00:55
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Quote:
Originally Posted by ghorrocks View Post
The run time is short because CFX is an effective and efficient CFD solver. Or are you suggesting the run time is too short? If so, what makes you think that?

To check if your mesh quality is a problem, then do another mesh with either a much better or a much worse mesh. Redo the simulation and see if it affects the results.

@ghorrocks THANKS A LOT FOR THE REPLY, i hadnt set the convergence criteria, after i set it to 10^-6, it took almost 2 hours. I am getting satisfactory results. Just a tip for others, run time largely depends on the geometry. A similar number of mesh for a different geometry took 3 days to converge.
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