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-   -   Boussinesq eddy viscosity assumption (http://www.cfd-online.com/Forums/main/85103-boussinesq-eddy-viscosity-assumption.html)

siw February 17, 2011 10:25

Boussinesq eddy viscosity assumption
 
Hi,

The Boussinesq eddy viscosity assumption is given at:

http://www.cfd-online.com/Wiki/Bouss...ity_assumption

where the Reynolds stress tensor contains the fluctuating components of the velocity components when they are Reynolds decomposed (http://www.cfd-online.com/Wiki/Reynolds_averaging).

My questions are:

1. Are the terms on the Right-Hand Side of the equation the instantaneous velocity, density and kinetic energy?

2. Would the eddy viscosity assumption be different if the Reynolds stress tensor contained fluctuating components of the velocity components when they are Favre decomposed (http://www.cfd-online.com/Wiki/Favre_averaging)?

I cannot find these answers anywhere.

Thanks

pavitran February 17, 2011 10:58

Hi
 
  1. They are average values not instantaneous.
  2. I guess the eddy viscosity assumption may not be different when the are favre decomposed.

siw February 17, 2011 13:30

Thanks for the reply.

Please can anyone explain the case for question 2?


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