Unrealistic Flow Pattern For Free Surface Simulation

[Anonymous]

Hi!

Tried to simulate free surface problem of falling a glass of water. A glass of water and water container (that will contain water later) was designed (2D). Glass was given an fixed angular motion to tilt from vertical position at an angle of 120 degree. From results, water was seen falling downwards but the flow pattern was unrealistic. In some places,its showing small amount of water penetrating  the solid glass geometry. Why is this happening?

Help me finding the problems. Support file of that attamped simulation was attached below.

Thanks!

[Jon.Wilde]

Hi,

Bear in mind that we cannot model surface tension/droplets so we may not be able to capture this at all.

We also need an excellent mesh, typically a uniform/manual one is best.

Feel free to share a CFZ file.

Thanks,

Jon

[Anonymous]

Hi!

Thanks for replying. Sorry, i forgot to attach the cfz file in my first post. Support file of that attamped simulation was attached below.
I'm not trying to visualize droplets/surface tension effects but it doesn't need more than 2s (approximate) to empty a glass full of water. But my current setup results showing its not fully empty after passing 5s!!!!
Help me finding the problems.

Thanks!

[apolo_vanderberg]

For a moving solid to "hold" water it must maintain 3-4elements through the thickness of the solid while it moves/rotates.

Look at the Free Surface Results video I did on SimTV as I performed the same analysis of a tilting/rotating glass with water.

Free surface plus motion is very mesh sensitive.

[Anonymous]

Hi!

Thanks for your reply. I watched your vedio in SimTV on Free Surface of a tilting/rotating glass with water, but there were very little information about setting up the Model.

If you could please share the CFZ file  you performed that would be very helpful.

Thanks Again 🙂

[apolo_vanderberg]

I do not have that sharefile as it was something I quickly set up and ran for the purpose of that episode.

The details of the setup.

A mesh refinement region where the moving solid starts and where it would move in to. (Covering the entire path of motion).

This mesh must be tight enough to maintain 2-3elements through the thickness of the solid at all times, otherwise the solid will 'leak'  Free Surace.