[Chrissi]

Hey everybody,

at the moment I´m playing around with the ImmersedBoundary Implementation in foam-extend 3.2. The first case I try to solve is a 2d cylinder at low reynolds number (40). As reference i take some literature and another case calculated with simpleFoam.


I´ve already done the simulations and my results match very good (simple look at Paraview, max.pressure, max.velocity etc.). The simulations are converging.

But when i look on the forces, the results of my simpleFoam simulation and my simpleIbFoam simulation are completely different.

So my questions are:

1. Is there something I have to take care when calculating forces with the Immersed Boundary Implementation? I don´t know much about the exact mathematical description, so perhaps I´ve forgotten an important point.
2. How are lift and drag coefficients calculated with IB? I didnt´t find a function for this and calculated them by hand. They didn´t match the correct results.


Thanks a lot for your help.

[GrpOne123]

i use pimpleDyMIbFoam calculate the forceCoeffs,and the force coefficient oscillates severely .Did you solve this problem？How did you fix it？