Rocket Exhaust Issue

[hunter_williams]

I'm getting some issues with a rocket exhaust sim. Not sure if it's a bug or I have a setting wrong.

I'm attaching the Maya scene.

I'm using Maya 2024.2, Vray 6.20.02, Phoenix 5.22

https://drive.google.com/file/d/1klx...ew?usp=sharing

[georgi.zhekov]

Hey,

Sorry for the late reply.

I tweaked a few settings here and got something like this.

1 - The particles were moving quite fast and the simulation couldn't keep up. I slowed them down a lot and increased the steps per frame to 2.
2 - The scene scale was a bit small so I increased it 5 times.
3 - The Phoenix Source was emitting way too much fire and smoke - I dialed down the discharge to 5.
4 - In the Phoenix Source I changed the Particle Shape to be set to use a Sphere with a custom size of 2. You can find more about particle emission here - https://docs.chaos.com/display/PHX4M...nfromParticles

Hope this helps!

[hunter_williams]

Georgi. Is the reason for increasing the sim scale to compensate for the small emitter size?

[georgi.zhekov]

The scene scale increase was to give a bit better fluid behavior to the sim - generally rockets would be larger objects (not justa few centimeters, but rather meters) so in order to compensate for the small scale of the emitter I bumped up the scene scale.

This makes the smoke move slower and to expand a bit more.