Wind Tunnel Visual Effects

Development Rendering
1

So, I happen to see this video on youtube showing some cars in a wind tunnel. The smoke blowing over the cars looks pretty cool and it got me wondering how one would go about creating this effect. I can think of various applications were an effect like this would be neat, not just for cars in wind tunnels.

I’m not a particle expert, but I’ve played with UE4 particles some what and I doubt this sort of effect would be possible out of the box as it seems like the particles would need to be affected by the shape of the object they are moving over, which implies some sort of physics. I know NVidia have their Flex system that may or may not be useful for this (not sure, never used it), but Flex isn’t very cross platform from what I understand and requires and NVidia card right?

Anyway, can anyone think of a way to create such an effect in UE4? Maybe particles aren’t the best thing for this?

2

It could probabely work with particles and vector fields that are created in an external application like houdini. I have successfully exported and used vector fields from houdini with this tool.

3

A vector field is precomputed (baked in) isn’t it? I was thinking of a way that would allow any mesh to be put in front of a stream of particles and have the particles sort of “flow” over the surface of that mesh, i.e. calculating the path on the fly rather than precomputing a path to follow.

4

You could go with making proper grid-based fluid simulation, thought it might be somewhat expensive.