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Steady vs transient

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Old   February 27, 2020, 08:42
Default Steady vs transient
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Rohan Iyer
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Can anybody tell me why when I run flow over a cylinder at Re=200 in steady and unsteady cases the results differ?
Or should they not differ?
I am getting less amplitude for lift in case of steady but in unsteady case I'm getting validation from literature
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Old   February 27, 2020, 11:30
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If your Re is based on cylinder diameter, then you are in the transition regime. Flow is not steady, hence, only transient simulation makes sense. In any case, transient results are better than steady-state, provided it has been run for longer than characteristic time.
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Old   February 27, 2020, 22:07
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Quote:
Originally Posted by vinerm View Post
If your Re is based on cylinder diameter, then you are in the transition regime. Flow is not steady, hence, only transient simulation makes sense. In any case, transient results are better than steady-state, provided it has been run for longer than characteristic time.
thanks for the suggestion
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flow across a cylinder, low reynold's number, steady and unsteady state

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