[Kutti]

hi

I'm more or less new to OpenFoam but I am doing a simulation of a Kaplan hydraulic machine at my University

Right now I'm just working with the guide vanes and my first step is that I wand to do a SteadyState simulation with SimpleFoam

my Mesh (of guide vanes) is ~2,2 Mio nodes. In most cases I am calculating in parallel with 4cpus

Until now I tried a lot of things and read a lot about SimpleFoam problems and Solutions in this Forum but still I get no convergence. Don't know what else to try....

U(mag) at Inlet is about 3 m/s
length of Guide vane is about 20 cm ........just that you get an idea of the case

I tried nearly all combinations of the following settings: (files attached below)

1. U initializations with potentialFOAM
2. No initialization with potentialFoam
3. fvSolution1 with GAMG for p (like Ercoftac centrifugalPump testcase)
4.fvSolution2 with standard settings (from tutorial case)
5.fvSchemes3 with laplacian limited

6. fvSchemes with laplacian corrected (like Standard tutorial case) brings always a divergence after 15 iterations (does anyone know why???)

"Because I am pretty new to CFD I also don't know the difference between Gauss linear limited and Gauss linear corrected for laplacian schemes."

7. Different Relaxation Factors for the fvSolution Standard Settings
a) p0,3 others0,7
b) p0,35 others0,65
c) p0,2 U0,7 k,e0,5 rest0,7

I did always 10.000 Iterations but it never converged....
Sometimes it diverged at about 8000 Iterations
Residuals never go below 0.0001 and in most cases doing waves ;(
Massflow difference between in and out is always ~0

So for about 2 weeks I read a lot of threads in the Forum and tried everythin that came in my mind....So right now I don't know what else to do...

Can someone give me a hint?
Do you need more information? I can provide everything.
Tanks a lot for your help!