How to modelize a free surface?
 

I would like to modelize a free surface. In a tank, two cylinders rotate contrarotatively. We put a very viscous oil in the tank and for a threshold rotation speed , the free surface is deformed and there is a singularity called "cusp". I want some help to modelize this 2D problem. Thank you Marc Legendre

Re: How to modelize a free surface?
 

Hello,

you should model this with the VOF (volume of fluid) model. It's in the multiphase panel. Choose oil to be the first phase and air to be the second.

Is this really a 2D problem? Is it an axisymmetric problem (axisymmetric swirl)?

good luck,

Laika, still orbiting

Re: How to modelize a free surface?
 

Thanks for your answer. This method doesn't work... My main problem is that the interface disappairs: after the simulation, their is air in the oil... What can I do? Thanks

Re: How to modelize a free surface?
 

turn on gravity and set the correct values.

In your solution controls, choose 'body force weighted' in combination with the PISO-scheme for pressure-velocity coupling. Set all the underrelaxations equal to one.

good luck,

Laika, still orbiting