Hi, I wonder what those are?

DNS and LES?

Are there any easy references for those?

Thank you~

DNS = Direct Numerical Simulation; LES = Large Eddy Simultion

For DNS you solve exactly the Navier Stokes equations in time and space. That's mean you have to use a grid fine enought to catch all the scales of the turbulence.

For LES, only large eddies are solve and dissipative effect of small scales is usualy modelize throught a viscosity (SGS model = Sub-Grid Scale Model).

You may look to the following article :

P. R. Spalart - 1999 - Strategies for turbulence modelling and simulations Engineering Turbulence Modelling and Experiments 4 - W. Rodi and D. Laurence (Editors) - Elseviers

It gives a good introduction to the different ways use to solve the turbulence problem in CFD. The bibliography of this paper may give you some indication about references you are looking for.

Sylvain

hi there,

check the following link: http://www.ionasoftware.com/gross/fl...urbulence.html

you'll find all the info you need about DNS & LES.

you can also go to Ugo Piomelli's publications website: http://www.glue.umd.edu/~ugo/research/publications.html

you'll be able to download a lot of papers and more about DNS and LES.

Sincerely,

Frederic Felten CFD Lab, UT Arlington. http://utacfdb.uta.edu/

Thank a lot, it is a great help.