Hi to everyone,
I am studying cavitation simulation using OpenFOAM interphasechangeFoam solver. It is turbulent flow. Therefore, someone could tell me that how can I stabilize the flow field before activating the phase change model.
Another question is that it is transient model, so how can I be sure that calculation converges at every time step?
Thanks in advance.
You can check convergence in OpenFOAM by plotting the residuals with GNUPLOT. For each time step the residuals should go down and then for the next time step the residuals will jump and start to go down again.
Hi to Dear Andreas and Christian
First, Thank you so much for your kind replies.
Dear Andreas: That was exactly what i want to do. First, let me explain What i tried:
1. First, i just ignored the phase change until the flow fields fully developed. I checked residuals exactly how Christian explained (using pyfoam via GNUPLOT)
2. And then, run the case with the phase change. As you can see at the attachment, my nozzle type is very simple because it is experimental type nozzle. Therefore, it is already known where the cavitation take place. Truely speaking, still i am not satisfied from the obtained results.
I would like to confirm your advice again. Could you tell me that you mean time step 1e-15 with minus? or without minus 1e15? If it is with minus, what is the advantage to treat the simulation with such a small time step? And, you also adviced to set the pressure maxIter=1000 during steady-state or transient simulation?
Thank you in advance.
Baris
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