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Karman vortex streets on a turbulent flow with k-eps model ?

Posted: Fri Jun 08, 2012 1:46 pm
by nicolas
Hi all !

Is there any way to find Karman vortex streets on a turbulent flow around a cylinder with the standard k-epsilon turbulence model ?

For my investigation, I used a domain which consists in a rectangular box (1.25 x 0.3 x 1 m) with a cylinder (D = 0.05 m) and boundary conditions as follows :
- smooth wall conditions for the upper and lower side of the box as well as for the cylinder
- a symmetric condition for the left and right side of the box
- a constant inlet velocity with a normal direction to the inlet. U_inlet ( ~ 0.9 m/s) is computed in order to obtain a Reynolds number around 34000.
- turbulent kinetic energy : k ~ 2.55 10^-4 m^2/s^2
- turbulent dissipation rate : eps ~ 1.92 10^-4 m^2/s^3
For the physical properties of the fluid , I use a density of 1000 kg/m^3 and a viscosity of 0.00129 Pa.s.
... but without any success !

Moreover, I tried to use a rough wall condition for the cylinder instead of the smooth one, and it works great...

Any help would be greatly appreciated

Best regards,

Nicolas