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Turbulence Production Based on the Curl of the Velocity Field

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Old   April 4, 2008, 06:22
Default Hi to all of you I hope you
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ngj
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Niels Gjoel Jacobsen
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Hi to all of you

I hope you are having a nice Friday morning.

I have been reading an article called "Simulation of Breaking Waves in the Surf Zone using a Navier-Stokes Solver". by S. Mayer and P.A. Madsen from ICCE 2000, pp. 928.

The part in that article which interest me the most is the linear stability analysis of k-omega model under non-breaking waves. As these are described by potential theory no turbulence should be generated. It is shown that the nature of the production term in this turbulence model actually extracts energy from the organized motion and produces turbulence. This is due to the production term being based on the mean strain rate of the velocity field.

What is suggested in the article is called an 'ad-hoc' solution, namely replace the known production term with a term which is proportional with the curl of the velocity field. They show numerically that no turbulence is generated under the non-breaking waves using this approach.

My question is, if any of your has been reading any articles/books/poster or anything using this approach. This would be very interesting to all who is modeling waves with a turbulence model. It should be noticed that I do not know if this non-physical production happens in the k-epsilon models, but as the production term is the same I would suspect that one could carry out the same stability analysis and come to a similar result.

Best regards and have a nice weekend,

Niels
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