initial fill shrinking + unexpected behaviour

[lukepenry]

I saw somebody else posted about this, but I didn't see a resolve, so i am posting my experience.

I was working on a scene when I encountered this, I then reproduced it in this test file.
Test File: https://www.dropbox.com/scl/fi/7tq78...8gad5epy5&dl=0

The initial fill seems to shrink by half when simulated and then has some explosive behaviour causing the simulation to be constantly the liquid to be thrown all around.
Example: https://www.dropbox.com/scl/fi/aaz5m...jqdmjk5xp&dl=0

If set the steps to 5 then the simulation shrinks less, and the explosive behaviour is minimised, although still present. It starts off light and get worse as the sim goes on.
Example: https://www.dropbox.com/scl/fi/2tc4w...za1cp9azn&dl=0

I have not encountered this issue before as it’s a very simple set up. Hopefully someone can shed some light on this.

Thanks!

[slavina.nikolova]

Hey,

In order to achieve a smoother liquid simulation, you could experiment with the following options:

-> Increase the Scene Scale - When working with small scale water simulations, it's often hard to control the tiny jittering that tends to occur near collision objects without increasing the Steps Per Frame to prohibitively high values. Therefore, it's faster and easier to simply increase the Scene Scale a little. If your scene setup requires lower Scene Scale, you can compensate this by increasing the Steps Per Frame at the expense of increased simulation time.

-> Decrease the The Cell Size - The lower the Cell Size is, the more detailed the simulation will be but the longer it will take to complete.

-> Increase the Steps Per Frame - Higher Steps Per Frame values will result in a smoother liquid at the cost of increased simulation times. In general, you should try to keep this as low as possible without compromising on the quality of your simulation.

To see how the water settles, you will probably need to simulate some additional frames. Please, also note that there is always going to be some movement in the liquid solver.

Here is a tutorial that explains in detail how to setup a scene with Initial Liquid Fill, along with some simulation and render tips - https://docs.chaos.com/display/PHX4M...ith+Containers


Hope this helps!

[lukepenry]

Hi,

I will accept that some jittering can be solved using some of these methods, although none really seem to, but i am still confused by the shrinking liquid, I cannot understand where it is going. The liquid seems to compress and not maintain the height of the of the initial fill object.