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Old   September 25, 2017, 06:50
Default Convergence Question
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Jepp S
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Dear Colleagues,

I am simulating a wind turbine, and my model is kw SST.

Screenshot here is the scaled residuals. Can you please help me judged if this reached convergence?

Thank you very much in advance!
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File Type: jpg Scaled Residual.jpg (130.5 KB, 32 views)
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Old   September 25, 2017, 07:44
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I think that something is wrong with your model or some transient behavior is going on because after 85k iterations this should be converged and it is clearly not, if something it looks like diverging or repeating.

This is CFX forum, there is a seperate one for fluent.
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Old   September 25, 2017, 08:01
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Jepp S
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Thank you very much for replying to my post. Attached here is the screenshot of the Lift and Moment Coefficient of the Airfoil. I think this is the trend expected for this simulation.

By "something is wrong is my model", is this mean that Transient SST, Realizable SST I will try? I tried both of them and the trend of scaled residual is almost the same, the residuals are going up and down. Or something is wrong with mesh?

Thank you very much in advance again for helping me.
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File Type: jpg Lift of Airfoil 1.jpg (42.3 KB, 23 views)
File Type: jpg Moment of Airfoil 1.jpg (41.0 KB, 20 views)
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Old   September 25, 2017, 09:20
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Also, attached here is the mass imbalance
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Old   October 3, 2017, 19:44
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Glenn Horrocks
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ghorrocks is just really niceghorrocks is just really niceghorrocks is just really niceghorrocks is just really nice
I have moved this post to the fluent forum. In future please post on the correct forum.
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Old   October 4, 2017, 01:12
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hi my friend, I am facing the same problem as yours
I am simulating VAWT using K-w SST model. and I am also getting strange results
since we have the same problem, would you mind if we contacted together using WhatsApp in order to help each others to finish this project.
we can exchange our experience and information at any time of the day.
if you agree please email me to m_elgadari@yahoo.com

Regards
Elgadari
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