Adaptive Grid not adapting to small and fast moving source objects

[gregvfx]

I am working on explosions, with small debris flying fast and I can't get the adaptive grid to expand to match the positions of the small debris...
If the grid is as big as the debris it is taking forever to simulate, even with a very coarse definition...
should I do multiple grid for debris? it seams impossible to manage, as I have quite a lot of small debris.

is there any tutorial out there that is going beyond the simple sphere exploding?

[gregvfx]

Also, how the source modifiers work?
For example, I want my discharge value to be multiplied by the velocity, so that if the source stops moving, it also stops discharging, or discharge a lot less
In the help it is said it is modulating, but is it multiplying or adding or what?

[gregvfx]

The Extra margin seems to help the adaptive grid working fine now...

[georgi.zhekov]

Hello,

In order to make the adaptive grid more sensitive you can lower the threshold and if the fluid is moving too fast you can adjust the extra margin values as you have found out.

As for the discharge modifiers you can use the Speed option (so whenever the object is moving it will start emitting).

I have made you an example scene how this works.

[gregvfx]

I am using a mesher of a Pflow and I have a feeling that the speed isn't evaluated...

[georgi.zhekov]

Yes, looks like we need to improve how it works with Pflow. Thanks for catching that.

[gregvfx]

workaround: I use the Pflow as a source and it seems to work
I get little puffs though even with 8 steps per frame which is making the sim very slow

[georgi.zhekov]

You can try and animate down to zero the motion velocity and the particle size of the source so you can avoid the puffs.