[Djub]

Hi everybody !

(in fact, this is the continuation of another thread, but with new data. Thus, a new thread ?)

This WE was devoted to the calculation of the wake of a simple rectangular cylinder in an homogeneous flow. My purpose is to "tune" OpenFOAM in order to have a correct behaviour concerning the Von Karman Alley, or Vortex Shedding.


Here are some characteristics of my run:

• Mesh: the side is 3 times refined near the cylinder, up to about a cell of 1 mm

• The SGS model is oneEqEddy with cubeRootVol delta.
• Schemes:
  • Time: CrankNicholson 1/2,
  • Grad et div: Gauss linear (everywhere but grad(U): cellLimited Gauss linear 1, div(phi,U) Gauss linearUpwindV grad(U),
  • Laplacian: Gauss Linear Corrected
  • Interp: linear
  • snGrad: corrected
• Solution: "classical" PCG/DIC tol 1e-6 for p, PBiCG/DILU tol 1e-5 for others
• pisoFoam with 2 correctors and 1 nonOrthoCorrector.
• Cache: grad(U)
• decompound on 8 cores using scotch
• Inlet: uniform u=3.3, k=0.1 and nuSGS=0.1
• Boundary Conditions: kqRWallFunction with default parameters

After some time, the solution seems quasi periodic.
A snap shot (arbitrary phase):

And zoom near the cylinder:


Any advice or comment concerning this run ?

The solution seems OK, but the Strouhal number is completely wrong: I found about 0,18, whereas the Eurocode says 0,06 (three time less!!!). What is that ? What did I make wrong to have so huge error?