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kkpal April 21, 2013 11:13

Does laminar mean DNS?
HI everyone!
I'm doing flow around cylinder at Re=100, and I chose laminar as the RASModel in RASproperties file. Dose it mean the simulation is running in Direct numerical simulation?

Lieven April 21, 2013 17:11

That is indeed what it means, pretty cool he ;-).

But note that if the flow is turbulent, a very fine mesh is required to get an accurate result. This is in fact already the case for you (you can check the discussion on the flow regimes at ). So to get accurate results for the Re = 100, you should:
* run in 3D
* do a transient simulation
* perform a grid sensitivity study (to find the required number of cells)

If any of the above is not achievable, you should keep Re < 40 in which case the flow should be laminar so that a 2D, steady state, crude mesh simulation should be acceptable (if it is an infinite cylinder). Note however that even in this case turbulent structures might appear due to numerical inaccuracies.



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