Simulating droplet deformation inside flowing plastic
 

Hello,

I am trying to simulate a drop deforming inside a flowing plastic and I have been having some issues. Instead of a continuous flow as seen in the image (3phase.JPG), I would like to see how droplets deform along the center of the channel.

Here are the steps that I follow.

1. I am using the VOF model with Explicit formulation. The flow is laminar. There are 3 phases. I create three materials: Air, Oil and Plastic with different properties. I go to phases and set air to be the primary and the other two are secondary phases.

2. Since I only care about the phase interaction between the oil and plastic, I setup surface tension there.

3. I used the Non-Iterative Time Advancement with Fractional Step but the solution did not converge. So I changed it to SIMPLE.

4. Now, I create regions for plastic and oil (OilandPlasticRegions.JPG). I Initialize and patch the regions. Now if I set the VF of plastic and oil to be 1, it gives me an error (Error.JPG). Should I just set it to be 0.5 each?

5. Contours of the volumes after patching are attached as well. The VF for air does not make sense to me since air is not supposed to be present in the inlet cylindrical area i.e. the green section (images attached). This can be eradicated by giving VF as 1 for plastic, but doing that I am not sure if I can set the VF for oil as 1.

6. After running the simulation, I do not see anything at all. The solution converges pretty early and the model remains how it was before. I do not see the flow of the plastic or the drop deforming inside the plastic.

What am I doing wrong here? How will I be able to correct this?