[Olivier Huet]

Dear all,

I try to simulate with OpenFOAM the impact of a droplet on a smooth and solid surface but I’m currently facing a problem… The rim behaviour during the spreading phase is not uniform and depends on the flow direction:
- Along the axes (red circle in the screenshot “RimIssue.PNG”): the flow is “cut” before forming some “fingers”.
- Diagonal (green circle in the screenshot “RimIssue.PNG”): the liquid forms some nice “fingers”.

The rim behaviour should be uniform but I don’t know why it is not the case in my simulation. I tried different courant numbers (0.4, 0.25, 0.2, 0.01) but it doesn’t resolve the problem.

You can have a closer look at the rim with “AlongAxes.PNG” and “AlongDiagonal.PNG” screenshots (bottom view). And you can see the dynamic with the gif “Drop-alpha-0_5.gif” (top view).

Here are the parameters of my simulation:
- Version: OpenFOAM v 4.1
- Application: interDyMFoam
- Boundaries:
o Wall: type: constantAlphaContactAngle; theta0: 120; limit: gradient; value: uniform 0;
o Atmosphere: type: inletOutlet; inletValue: uniform 0; value: uniform 0;
- Drop: diameter: 500 µm; initial velocity: 10 m/s, centered, the initial distance between the centre of the drop and the wall is 300 µm
- Mesh
o Dynamic: 4 levels of refinement for 0.001< alpha < 0.999
o Block: cubic shape, Height = 1500 µm, Width = 4000 µm
o hex (0 1 2 3 4 5 6 7) (80 30 80) simpleGrading (1 1 1)
- MaxCo=0.2
- Two phases: air/water

I hope you will help me to find what’s wrong.

Let me know if you need any more details.

Cheers,

Olivier.