Smoke constrained by objects I have a smoke emitter that is under a rocket (but not touching anything). It emits smoke, but the smoke just sits there in a bubble. It doesn't flow. If I move the emitter away from the collision objects, it works fine. It's like the smoke won't get within a meter of any collision object, and this is a threshold that I can't seem to edit. Any ideas?
Have you checked the boundaries of the Smoke Domain?

The Smoke Domain is a cube that determines the limits of the simulation of the smoke. It cannot escape it. The cube can be resized and it's shape changed, of course.

Here's the relevant page from the Blender Manual for 2.79.