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Removing convex shape

Message 1 of 3
181 Views, 2 Replies

Removing convex shape

Hello, I have a falling liquid but I want it to fall straight down. Bifrost always wants to put a convex shaped like a drip. I have changed the viscosity from 0 to 1000 and even made the animation much slower and the gravity .01 but it always thins out in the center.  Anyone know how to fix this?  Thanks.   -Derryl


Screen Shot 2022-06-10 at 4.39.48 PM.jpg

Message 2 of 3
in reply to: Parmenides



The tapering happens naturally because of acceleration. Even with the low gravity, the acceleration adds up especially over a longer animation. At higher speeds, the liquid covers a longer distance per unit of time so it must be thinner to preserve volume.


You can set gravity to 0 and use a motion field to make the liquid move instead. Set the direction to -Y and the magnitude as desired, and clamp the min and max speeds to the same value so that the speed is constant. You can also set viscosity back to 0 because it won't have an effect in this case and just causes unnecessary computation (viscosity is resistance to shear, and there won't be any shearing if everything is moving at the same speed).


I hope that helps,


Grahame Fuller
Learning Content Developer
Message 3 of 3
in reply to: Parmenides

I ended up translating the emitter up and filling a tube as a collider. Your method would probably have worked better. Thanks. 

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