flickering geometry: how to solve this problem?

[cecofuli]

Hi,
We are going to make a simple animation. We are testing Phoenix FD (DEMO) to see f it's be useful.
We have to fill the object with a "dense foam" (it's a saddle motorcycle).
With the settings you are able to see in the screenshot, the animation isn't so bad.
The limit of 2M particles int' s problem 1.6 M are enough. Also, I change the step per frame = 4 and viscosity.
But the geometry has a strange flicker, especially on left part of the geometry.
This area is completely filled with liquid, but it continues to shake.
I would like to know if there is some parameters like "when the particles are slower that x, stop to move" or something like that.
Thanks you.

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[Svetlin.Nikolov]

Hey,

Would it help if you enable Mesh Smooth from the Rendering rollout? You could also make sure to export the liquid particles and try the 'Use liquid particles' option for the mesh smoothing too.

Cheers!

[cecofuli]

Hi Nikolov. Thanks for the fast support. The problem is not how to smooth the geometry. I used Mesh Smooth = 2, plus add a Relax modifier. This improves the bit of animation, and the problem is that the particles are still moving.
When particles filled up the left part of geometry, they should stop to move at all. Only in this situation, the animation will be flickering free.
I mean, when the particles reach a "minimum speed limit", they should stop move.
Is there some parameter like that? Or, maybe, are there some parameters that can improve this behavior?
PS: I turned ON Use liquid particles, but nothing happens. Do I much to change something =) (EDIT= I have to change Smoothness up to 3 to see something) Sorry, but I'm very new to Phoenix ^_^

[Svetlin.Nikolov]

Hm, if nothing happens, does changing the particle radius affect it? The thing is that currently Phoenix meshes particles by converting them to a grid and then meshing that grid, so with a very low resolution the voxels will switch between states and the surface will jitter. This is why with a demo version the best you can do is to try and smooth the mesh instead of increasing the sim resolution. However, if you can verify that the particles are still moving by turning off the mesh preview and enabling the particle preview for the liquid system, then you could try to damp their movement using a force - e.g. the Phoenix Plain Force has a drag parameter that will suppress the liquid's movement. You could use this and eventually animate the range of the plain force in time in order to gradually freeze the parts of the simulation that have already filled the shape.

[cecofuli]

Nikolov, the Phoenix Plain Force can be a good idea =) I will try to understand how to use it and I will tell you

Yes, the particles are still moving. Very, very small. But it's enough to change the mesh topology and flicker the final mesh

About the liquid particles, I solved by changing Smoothness up to 3 ^_^