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pvc January 1, 2007 21:25

Turbulence vocabulary
 
Hi everyone and happy new year,

I have a simple question today, which is :

Is there any major difference between the entities Reynolds Stress Tensor (RST), Reynolds Stress Model (RSM) and Differential Stress model (DSM)?

My feeling is that authors use numerous names but are talking about the same approach (using a differential equation for each term of the Reynolds Stress tensor). Since nobody until now confimed me that, I post here this.

Regards

pvc

opaque January 2, 2007 08:03

Re: Turbulence vocabulary
 
Dear pvc,

They are and they are not..

Reynolds Stress Tensor is the "thing".

Reynolds Stress Model is how you compute the "thing" or RST. For example, the Boussinesq hypothesis allows you to compute RST from the solution of two turbulence scales (k-epsilon, k-omega, k-kL).

Differential Stress Model, is another model of how to compute the RST. This one is based on the solution of a differential transport equation for the RST. Careful that the equation must be treated as a tensor, and not single scalar components. This will save you a lot of trouble when dealing with symmetry planes, and periodic boundaries.

what RST, RSM and DSM have in common is that you are talking about turbulence modeling, and you are trying to find your way to come up with a meaningful result.

Opaque.


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