When Flow is set to Collision on the plane, how come there's a space between the smoke and the plane collision? If I move the plane higher up, it doesn't seem to have that gap.
The gap is equal to one voxel size, so to decrease the gap you'll need to increase the resolution divisions. Moving it down and back up does seem to remove the gap in real time, but if you play back the animation again the gap will re-appear. A workaround is to bake the simulation and move the collision object to the right spot. Not optimal, but that's just the way it works at the moment.
