[MarioM]

Dear Foamers

I have to simulate two-phase flow (liquid-liquid and air-liquid) in small gaps of about 10 - 20 um thickness. Due to the geometry, I need a fine mesh with cell sizes in the micron range. I further have to apply pressure differences in the range of severel 100 bar, so that the resulting velocities are in the range of 1 m/s to 50 m/s, depending on the specific model.

With this setting, I have to use very small timesteps below microseconds. However, the desired simulation time is in the range of seconds. The multiphaseEulerFoam seems to become unstable using Courant numbers greater than one. Thus, my simulations take really long time, making prototyping and testing almost impossible. Parallelization doesn't help here of course.

Therefore, I'd like to ask if there's a common strategy or specific solver settings to overcome the Co restriction or to speed up the simulation in general.

Thanks in advance.
Mario