Learning Forum

[Navsing]

Hi,

I'm simulating droplet impaction upon a structured surface. I have modelled only a quarter of the domain to reduce simulation time.

I tried to patch a droplet at the symmetry plane using region cell registry, however the mesh at the interface of the droplet appears to be distorted compared to the rest of the domain.

This problem is affecting my results and cannot seem to solve this issue. Any help would be appreciated.

Thanks.

[Rob]

If you put an iso-surface through the domain about halfway up the droplet how does the mesh look? Patch can't alter the mesh, but I also don't know how you've built it.

[Navsing]

Here is what it looks like. I used mesh adaption to refine the mesh in the bottom half and top half as two seperate regions.

[Navsing]

Sorry for the posts. Wouldn't show up on my side

[Rob]

Don't worry, the site's not loading well this side either. I'll do some tidying.
Other than not knowing how you've got a hex surface mesh & core with a tet layer that looks fine. The distortion on the droplet is mesh related, and shouldn't be anything to worry about. In Fluent when you patch VOF use the smoothing options (bottom left of the patch panel).

[Navsing]

Thats fine. I think I've solved the issue. I used hex core meshing instead of hex dominant which gave me that tet layer. And will do.

[Rob]

Don't use hex-dominant method. It's for Mechanical and the mesh quality is generally awful. Hex-core or poly-hexcore (Fluent Meshing) are usually pretty good, but for VOF I tend to use pure poly mesh to avoid any jumps in cell size at the free surface.