[shock77]

Hi,


I am using the kOmegaSSTDES turbulence model with rhoCentralFoam. I am questioning my boundary conditios for k, nut and omega. Since my mesh is coarse near walls, I am using wall functions:


k: type kqRWallFunction; value 1e-10;

omega: type omegaWallFunction; value 1e2;

nut: type nutkWallFunction; value uniform 0;




Still, nut and k become quite large near walls and are nowhere close to 0, like it should actually be atleast for nut, since the kqRWallFunction is basically a zeroGradient BC. Nut is always bigger than nu. I have read in a paper (http://www.tfd.chalmers.se/~hani/kur...DES-Report.pdf) that they have used a fine grid near the wall (y+ below 11) and used fixedValue with (1e-10) k and nut (0). This was for openfoam2.x.x. Actually I am modeling supersonic jet steam and I am interested in the shear layer of the jet. The walls are actually not of interest, but I have to apply the right boundary conditions to them.



So my question is are wall functions implemented in the DES model and why do I get those large values for k and nut at the walls?