[JakeB]

Hi all,

I am attempting to perform a ship hull resistance analysis using open channel multiphase flow. My project supervisor believes that the streamlines in the air region are incorrect, and as such believes the whole simulation is incorrect. I have attached images of the streamlines, as well as the volume fraction and isosurface images extracted from CFD-Post.

I am using pressure inlet and outlet boundary conditions with a set free surface level, with an inlet velocity specified at 1m/s (gravity enabled). I am not generating any waves. For this simulation I patched the volume fraction of water into its specific region, and have tested the simulation again using open channel initialisation protocols with the same effects. I am using the default k-omega turbulence model. This is a steady state simulation, but I am not opposed to trying a transient simulation.

I am just looking for verification into whether the movement of air is abnormal, as my supervisor believes, or if this is typical VOF open channel air flow.

issue.jpg
main keel closeup.jpg
main keel vel.jpg
veloicty streamline.jpg
water.jpg

Thanks,
Jake.