[Avni]

Hi everyone,
I'm trying to do an analysis for high shear rotor-stator mixer for master thesis.
I use 2 material for mixing , silicon oil and water. I have silicon oil properties such as viscosity and density. But my problem is silicon oil goes after just 1 circulation in rotor it's viscosity changing. So here is some question that I want to learn thanks for help for now...

1- I know viscosity models (power law especially).I have k and n values for viscosity models and I can define max and min viscosity for my problem but I'm confusing select multiphase model, in the first time when we setup fluids there is strong interface between fluids but after some circulation in rotor and hits stator they are mixing each other. I want to see strain rate,and shear between rotor and stator gap.(I use VOF model but still I'm not sure)

2- I started analysis with VOF model because firstly we have strongt interface and also I want to analysis just after 1 revolution so I select this..

Boundary Conditions ; siliconoil inlet, waterinlet , outlet

Siliconoil inlet : volume f = 1 , water volume f=0 , velocity 0.8 m/s and
Turbulent intensity: %5 , Turbulent Viscosity Ratio=%10

Water inlet : volume f=1 , siliconoil volume f=0 , velocity 2.5 m m/s and
same turbulent specifics..

Outlet : Atmospheric Pressure and default for turbulence settings

I use PISO for scheme and Prestofor pressure discretization also first order turbulent kinetic energy and dissipation rate , second order upwind for momentum. I use time step which make my courant number less than 0.25
after some iterations turbulent viscosity limited to viscosity ratio notice come and analysis goes divergence .

I initialize system and also patch with water and no siliconoil with beginning... My mesh is not perfect but I don't think mesh is the problem.