Air and Water VOF model, Error??
 

I am simulating an empty tank filled with water (water inlet is at bottom of the tank, air outlet at top) using a VOF model. Although I turned on the gravity and body force options, the results show that the air and water are mixed together rather having a clear interface with water at the bottom and air at the top. Who can tell me what's the problem? Thank you in advance.

Re: Air and Water VOF model, Error??
 

What type of VOF you are using ? Fluent offers 4 type, right ?? DC

Re: Air and Water VOF model, Error??
 

Thank you. There are three types of discretization schemes for Volume of Fluid (VOF) offered by Fluent. I tried Implicit and Geo-Restruct. The problem persists. Looking forward for your advise.

Re: Air and Water VOF model, Error??
 

Use Geo-Restruct and also use VOF under relaxation 0.5. Try to use gradient of VOF after few time steps. You should be fine.

DC

Re: Air and Water VOF model, Error??
 

Thank you for your quick reply. For Fluent 6.0, there is no under relaxation factor with Geo-Restruct. What do you mean by "gradient of VOF". Looking forward for your reply.

Re: Air and Water VOF model, Error??
 

Try to adapt the grid based on the gradient of volume fraction of one phase.