[SOLVED]FLIP Timescale Has No Effect?

[Atom]

Hi All,

 

I have a static flip tank and I have introduced motion via an animated pulse using the Velocity Impulse Force. After I keyframe the force back to 0.0 I then animate the TimeScale of the FLIP Solver from 1.0 to 0.25. I want to see the fluid move in slow motion after the initial velocity pulse. Changing the timescale, however, seems to have no effect on the particles already in motion.

 

How do I make the FLIP solver Timescale affect particles already in motion?

 

I am attaching my setup if you have time to take a look.

 

Thanks

ap_FLIP_time_scale_issue.hipnc

Edited March 6, 2015 by Atom

[Atom]

I actually solved this one and put together a short tutorial on how I did it here.

[LaszloFX]

Awesome info! Thanks for sharing.

[John Svensson]

Hi

Has anyone played around with a animated time scale on the flip solver recently?

I'm on Houdini 15.5 and I've run into some problems with this. For me everything works by default when I animate the time scale on the flip solver. I take it from 1 on frame 20 to 0.05 on frame 30, and after a while I start to get some weird results in some areas that should be pretty static.

Seems to have something to do with velocity building up over time on certain points.

I've tried to follow Atoms Vimeo video, but first of the flip solver has changed some from version 13. And when I look at the rest of the nodes on that level, many more of them also has a time scale parameter. It's expression linked in some cases here and there, some with Update Always and some not at all. Feel like I don't know at all what I'm doing there.

Is the time scale on the flip solver suppose to work with animation? Is there another way to get the same effect without doing any retime post sim?

Thanks

/ John