[siw]

Hi,

I need some help in understanding some points about the Favre averaged Navier-Stokes equations which I've come across whilst doing the derivation from the instantaneous Navier-Stokes equations.

The references that I've been using are listed below but there seems to be issues that are not explained in them.

1. http://www.cfd-online.com/Wiki/Favre...okes_equations
2. Jonas Larsson's Ph.D. Thesis.
3. Turbulence Modeling in CFD by Wilcox (textbook).
4. Computational Fluid Mechanics & Heat Transfer by Tannehill et. al. (textbook).

I don't know how to write equations here so I have attached a Word file with them in where I've tried to follow the equations as posted on the cfd-online wiki page.

To make my queries easier to understand I have written them in the appropriate places next to the equations in the Word 2007 file. I had to zip the file because I could not upload a .docx file type.

Also, if only the velocity and thermal variables are Favre averaged and the density and pressure are Reynolds averaged then why are the viscous stress and heat flux terms not Favre averaged? These are based on velocity and temperature derivatives so surely they should be.

I'd would be really grateful if anyone could take a look at my file and help with the questions because I've gone as far as I can by trying myself.

Thanks.

[siw]

Can anyone help with this? Thanks.

[cincin1234]

hello, have you done reynolds stress deduction?

[usv001]

Hello everyone,

I have added some identities in the word doc that will help clear up most of the problems mentioned in the post.

Cheers.