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Luchete80 July 17, 2012 07:34

Fvm Solution Oscillations
 
Hi all!
I'm writing a fvm code for incompressible flow following the Blazek's book (like the freeCFD solver):
- stationary flow
- coupled solver
- colocated arrangement
- dummy cells
- gauss gradients for cell centers
- averaged gradient w/ some correction for viscous fluxes
- Piecewise linear velocity reconstruction for left and right state, simply with gradient at center and the distance to the wall (up=grad x r)
I began w/ an upwind which simply averages the left and right state.

I realize that the solucion oscillates in velocities and pressures.
I was wondering if this scheme needs is a correction like the Rhie-Chow for colocated arrangements, or if the left and right scheme w/ the gradients used simply accounts for this correction (According to Blazek's book, the correction scheme used for the gradient walls prevents oscillations).
I was checking out freeCFD code and i did'n find out a correction like this.

Can anybody help me out?
Thanks to all!
Sorry my poor english!!


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