Best way to create smoke drifts?

Software Support & Suggestions
1

I’m trying to create a long smoke drift, but the smoke always seems to dissipate too quickly. I’ve been messing about with the decay values in the sim, but not really getting the smoke to hang in the air. Not really looking for fast moving smoke either, so cranking the wind to get longer drifts won’t appear to work. Anyone know the best way to get this effect? Thanks

2

Ok, so I re-sized the container and now that’s a bit closer to what I want. But I’m having a hard time making sense of this container sizing. The voxel size remains constant, so why does just changing the bounds of the simulation container, make such a difference to the overall results?

3

So if you click the “show limits” button in the viewport that will show you your current bounds. The voxel size does indeed remain constant but perhaps the smoke was softly decaying against the edge and you just couldn’t tell that it was the edge of the bounds. Changing the voxel size changes the container size and that allows the smoke to travel farther. If you do change the container size and show your bounds, make sure you move your emitter to the edge in the opposite direction of the wind. Here’s why:

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The red box is the original location of the emitter, and the green box would be where the smoke could go if the wind were blowing to the right (it is in this case). On the left side it would be completely empty and wasted space for your bounds. Thus you move the emitter all the way to the left to ensure you’re maximizing your space usage.

4

Thanks Nick - that’s helpful! :+1:

5

Ok, so got what I wanted, but Embergen is crashing everytime I try to export to VDB’s. Where do I need to send bug reports, files and steps to recreate?

Thanks

6

Don’t worry - think I just found the right place!