Gas simulation (in a vacuum)

In my current project I would like to have cold gas thrusters and a rocket engine. These would be in the vacuum of space so the smoke wont look right for it. I’ve tried volumetric shaders, particles, and smoke but I can’t seem to find a solution. Any suggestions on how to go about this?

Here are some general examples. Is there a way to make these aerodynamic effects or clouds?

For the clouds there is this tutorial:

The other effects I would consider indeed more challenging. Although you actually might get something usable with the smoke sim. Hints:

  • if you set temp diff to zero, you won’t get rising smoke, appearing like there is zero gravity
  • setting initial velocity on the flow object would likely be a must, to get this kind of ‘high-speed’ appearance
  • for this particular look vorticity should be in the lower range, I guess (I’m not familiar with supersonic fluids, and it certainly isn’t physically correct what the smoke sim does for this, but it might not matter)

Faking everything with procedural textures for the volume shaders sounds promising, too (at least for this still image). It’s not completely trivial, so probably only an option with some experience with procedurals.

In that image it looks like there is volumetric clouds and tail of rocket is some “cylinder” with emission shader that lights those clouds. There can be also some two dimensional density map to control cloud heights in location where rocket was launched.

If you want to animate this, I recommend using particle emitter to tail of rocket where particles have initial velocity same as your rocket engine gas exhaust speed, and set those particles to be as smoke emitters and set temperatures and smoke to be flame that cools down to water steam. Wing vapor and supersonic effects you need to build separately.

Real limitation is the scale and smoke domain size. You should not use 1 unit -> 1 meter. Instead use scale 1 unit -> 1 km, set smoke domain height up to 10 units (10 km) and move it as rocket moves, so you get 10km tail of flame and water steam.

This kind of result should be possible: https://www.youtube.com/watch?v=kNOhNLk0mRQ

When I looked video more carefully, exhaust gases are less than 1km. So 1km x 1km x 1km box behind rocket should be fine and that kind of shape should make that launch cloud when particle stream is hitting ground.