Modelling of the turbulence for aeronautics
 

Hello,

I'm a French student. I have a project to do for my studies. I have to search which are the models used for turbulence modeling in aeronautics applications and particularly for the wing plane profil conception.

I have to find the Mathematic developpement and the reason why the model is a good model.

I found information about RSM but I didn't find why it's a good model for aeronautic. My teacher talk me about k - omega model but I didn't find anything with the use of this model in aeronautic.

My principal problem is to find "why the model is a good model for aeronautics applications ?"

If somebody thinks he can help me, do not hesitate, I take every information.

Sorry for my poor English level.

Thank you in advance.

Pierre

Re: Modelling of the turbulence for aeronautics
 

The Spalart-Allmaras model has been developed at Boeing

Re: Modelling of the turbulence for aeronautics
 

The most popular turbulence models are Spalart-Almaras, k-epsilon, k-omega and SST. SST (shear stress transport) is a combination of k-epsilon and k-omega and is in my opinion the best model for a wide range of applications. Spalart's model is very good for airfoil and wing flows. A literature search on any of these models should provide you with more information than you can possibly use.

Re: Modelling of the turbulence for aeronautics
 

Get hold of the Wilcox book, "Turbulence Modelling for CFD". Describes them all very well both at a mathematical and physical level. However, Joe gave a pretty decent round-up of the best models. It's good to know that Wilcox's latest revision of the k-w model performs very well for a variety of wall-bounded flows, whereas the k-e model performs better in free-shear flows (rotating flows in the freestream ie vortical flows). Hence, the combination of SST being so popular. Take a look at the book (or even the wiki page here of each model) and try and get a better understanding of the transport equations and what they entail.

Re: Modelling of the turbulence for aeronautics
 

Hi,

SST in itself has nothing to see with "the combination of ke and kw".

Blending the ke and kw is the Baseline model of menter, similar to others with a cross-diffusion term, which is added to avoid any far-field boundary conditions influence on the BL.

The SST modification is linked to the realisability principle, or in other words, to limit the eddy viscosity levels with more or less links with the Bradshaw hypothesis within the boundary layer. Like other similar realisability "limiters" (Durbin, Moore & Moore, Kourta, etc.), you can apply it to any widely used turbulence model (ke, kl, kw, etc.).

Regards

Re: Modelling of the turbulence for aeronautics
 

Thank you very much for all this responses.

I found a lot of information on this site and in others about SST Model. I wish I did a good job for my project. Praise in the merits of case, I learnt a lot thanks to tracks that you gave me and that I deepened.

Thank you

Re: Modelling of the turbulence for aeronautics
 

Here is a paper by Menter (not the original paper) from the NASA website. Have a read for yourself.

http://ntrs.nasa.gov/search.jsp?R=327267&id=2&qs=N%3D4294765664