Fluid Force Operator Help

[spewdog]

Hey all, 

Just curious if anyone would know why the top of this block does not fall fast as soon as the fluid force hits the bottom. The veronoi fragments are bound together, but after they break, I expect the tower to fall down, but as you can see in the video, it just slowly lowers. I've been trying to figure it out for ages and just cannot fix it. 

I'm using Phoenix 3.14
TyFlow v16059
Fluid's velocity is being outputted

Any help would be greatly appreciated, cheers!

[shadowkiller]

Looks like you're missing gravity. Try adding a force operator and set gravity in there.

[spewdog]

Looks like you're missing gravity. Try adding a force operator and set gravity in there.

Cheers for the suggestion

PhysX uses gravity by default so adding another just adds to the effect. However I have narrowed down the issue a little, still can't solve it though haha. It seems that if an object is inside the Phoenix grid, it follows the fluid particles, but if it is in "open air" it slows. I put a box above the grid, it falls with gravity all good, but as soon as it goes inside the grid, it comes to a slow.

[d4rk3lf]

Well, it kind of makes sense, because fluid force is affecting the PhysX dynamics (if not - overwrites them) 

Why don't you try and setup 2 Tyflow systems? 
One is driven by fluid force, and they could be small spheres (set PhysX kinematic on them), and the other is the wall with Regular PhysX. 
Try using trigger PhysX collision (inter particle), or maybe just test by time. 
Or you can even make 2 Tyflows... 

I don't have time to test it now, but I will definitely try something like this myself.

[shadowkiller]

What do you have your fluid force set to? Add, blend or replace?

You can also add mass to your physics pieces and then enable the relative to mass option in the fluid operator. That should allow you to adjust how much influence the fluid force has, based on the mass of the object.

[spewdog]

Well, it kind of makes sense, because fluid force is affecting the PhysX dynamics (if not - overwrites them) 

Why don't you try and setup 2 Tyflow systems? 
One is driven by fluid force, and they could be small spheres (set PhysX kinematic on them), and the other is the wall with Regular PhysX. 
Try using trigger PhysX collision (inter particle), or maybe just test by time. 
Or you can even make 2 Tyflows... 

I don't have time to test it now, but I will definitely try something like this myself.

Cheers! Yeah I have experimented with this method before, it does work effectively, I added a vid of how it turns out. I found it works better not setting the particles to kinematic as they just smash everything they hit at 100%. However just normal settings they seem to behave more like 50 - 80%, but that's probably the size and frequency of the particles too.

shadowkiller

What do you have your fluid force set to? Add, blend or replace?

You can also add mass to your physics pieces and then enable the relative to mass option in the fluid operator. That should allow you to adjust how much influence the fluid force has, based on the mass of the object.

I was using Replace. Cheers, I switched to Add and got some better results, however I had to drop the influence to 10% and it's still a bit frantic, any lower and it takes to long for the block to react. I fiddled with the mass influence too and still could not find a good result. Guess as a short term I can use the Fluid Birth method, but was hoping to skip the extra sim step.

Thanks both for your help.

[d4rk3lf]

Hey I really like how that Fluid_Birth_Method turned out. 
Now, you could experiment with more complex fracture, or complete new scene (for example, house being destroyed by water wave   ).

[spewdog]

Hey I really like how that Fluid_Birth_Method turned out. 
Now, you could experiment with more complex fracture, or complete new scene (for example, house being destroyed by water wave   ).

Haha, that's actually exactly what I'm doing