fire with 0 gravity

Development Programming & Scripting Blueprint
1

Hi, I want to create a fire occuring inside a spacecraft. Any tips/idea on how I could proceed?

2

Hey @jodebelle! Welcome to the community!

You would think you’d like to get an existing niagara fire or make your own, then just rotate the emitter to match the wall. However, upon a little research, I discovered that would not be the case (see the article below). Gases would intermingle in a 0-gravity environment- hot and cold air would be unaffected by their weights in relation to floor or walls, it would all mix together. The flame itself would be almost spherical, so maybe find or make a good lingering fireball effect to work with and then use a post-process effect to reduce visibility due to the carbon in the air?

Disclaimer: This link is not associated with Unreal Engine, Epic Games, or their partners.

3

@Mind-Brain Thank you very much for your answer! Indeed I saw that fire would appear in a hemispherical shape with microgravity. I am trying to represent a spherical shape without a sphere static mesh which is made of many many triangles and thus slow the thing down. Also, I want to make them “float” in a way to represent microgravity, any idea on how I could do that? And finally, I want to extinguish those fireballs, I have the extinguisher but I don’t know how to create a radius of oxygen to come out of it. If you know anything about this, your help would be greatly appreciated:)

4

Hey again @jodebelle!

So a few things to answer here:

  1. You can give an actor (let’s say BP_Fireball) a Niagara effect to give it that see-throughy plasma effect, and give it a sphere collider instead of using a static mesh.

  2. The floatiness really would depend on how you use them. There are a ton of ways to go about this but it’d be hard to give you an accurate method for your use case as there are just as many use cases as there are ways to achieve this.

  3. As for extinguishing, apparently fire puts itself out in microgravity?! Because the rising heat and plasma allows oxygen to come in from underneath with normal gravity, zero g environments prevent this. Things like stars are different because of just how massive and gravity producing they are.

  4. Not sure what you mean by creating a radius of oxygen… shooting a flame with oxygen in zero g would actually possibly have the opposite effect and make the flame bigger/make it shoot up into the extinguisher.

  5. If you wanted an extinguisher you could do some sort of glue-like substance like in Prey 2017, make a projectile that on collision with flame would destroy the flame and spawn a rocky static mesh on location before deleting the projectile. That’s just an idea though.