Learning Forum

[dmr011]

Hi,

Here is a picture of the vertical velocity field after 28 time steps, with each step being 0.00025 seconds. The upper portion is gas phase and the lower portion is a liquid mixture that is primarily water. The geometry is cylindrical except for the channel on the right side where there is a flat wall. The interior geometry is seperated into two regions of fluid that can be easily identified in the attached picture. 

For patching, I patch the volume fraction of each species in the mixture for the liquid then patch the volume fraction of water as 1 as the last species. The gas phase is simply one component and also patched as a volume fraction of 1. 

All boundary conditions are set to zero flux. The only boundary conditions with motion are the inner cylinder which is rotating at 41.88 rad/s about the central axis. I have also tried without the rotation and it gives the same issue. I am also setting electric potential boundary conditions at the flat wall on the right (1V) and the central third of the inner cylinder that is submersed (-1.2V). However, I also get this issue when I set both potentials to zero. There are supporting ion concentrations of 0.1M in the mixture. I also don't have any thermal effects activated. 

I am using the volume of fluid multiphase model. I have also attached a screenshot of those settings. 

The problem does seem to go away when i deactivate the electric potential model. I am trying to model electrochemical reaction in this aqueous system though, so the potential is going to be necessary. 

Any ideas?