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cristobal May 4, 2011 20:27

wall functions and boundary conditions in OF 1.7.1
Hi everyone,
I am running a case of flow past an airfoil using simleFoam and the kOmegaSST turbulence model. I have a y+ of less than 1 everywhere. When I use wall functions it runs ok, but it doesn't quite reach the free stream value of k that I specified in the boundary conditions. When I use the FixedValue condition at the wall, the boundary layer gets way too thick. I am not sure what the value of omega should be at the wall, in theory it should be 0, because k=0, but when I specify that value the solver crashes. I tried a very small but non-zero value and it runs, but with the BL grows too thick.
I am not sure if using wall functions is justified if y+ is less than 1, can anyone give me some advice?


The King May 5, 2011 10:50

Wall functions
For turbulance, there are two methods close to the wall. Wall functions for y+ > 30 or integrating to the wall. See

Good luck!

romant May 6, 2011 04:10

if you wanna run this case in low Re approach, consider the following link it will give you the right boundary conditions and some suggestions on how to use the OpenFOAM kOmegaSST model in a low Re (y+<1)

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