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Old   June 25, 2012, 00:12
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Sijal Ahmed Memon (turboenginner@gmail.com)
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Thats secret behind success of eddy viscosity turbulence models for many types of engineering flows to find out mean engineering quantities. Thanks.
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Old   June 25, 2012, 00:21
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Once the equation are averaged over time and space (ensemble average, please correct me, if it wrong). then I find two situations very interesting.

1. We are trying to find out the fluctuating components through RSM model. In this case it is only giving you only the RSM values of them instead of true turbulence. Well I admit that RANS only model the large eddies.

2. Running the unsteady simulation to find out the transient solution from the averaged qualities.

I also find it out it very confusing situation that when we make the Reynolds averaging, we get the NS in terms of mean quantities except Reynolds stresses.
Then to find out these components, we need to express them in terms of mean quantities. Whats the point?

PS. May be I am confusing the concepts. So this may be the good chance that I get corrected by some expert.
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