Smoke collision and smoke cache

Hello, I have two questions.

  1. Is there any way to decrease the collision distance between smoke and mesh?

  2. Why is the smoke cache option in the smoke domain grey?

Thank you guys need your help for a project.

  1. Why is the smoke cache option in the smoke domain grey?

Sounds like you haven’t saved your blend file.

thank you, what about question 1?

Smoke doesn’t even touch the mesh, it collides before it.