Border Collisions

– Controls which sides of the domain will allow smoke “through” the domain, making it disappear without influencing the rest of the simulation.

Open: Smoke disappears when it hits any side of the domain.

Collide All: Smoke collides with all sides of the domain.

Vertically Open: Smoke disappears when it hits the top or bottom of the domain, but collides with the walls.

Blender Smoke Border Collision