Containing fire within an object

[AlFong]

Hi,

Does anyone know how to put a fire inside a hollow object (like a tube) and make sure the fire/smoke doesn't show outside the object? I don't want to scale the bounding box, because I want the smoke to be able to fill a larger area after it exits the object.

I've attached a picture showing what I'm trying to do. Picture the tube as a trash can, and I'm trying to constrain the fire inside the trash can until it comes out the top. I don't think I can do it just by scaling the fire source because the final object won't be straight up and down, it will be curved.

[AdZanetti]

I think i can answer that one, seems pretty easy.

there are several ways to fix your problems, i'd say it's rather simple.

1 - add an object in your sim that allows the fire to be constrained, so it collides at the root, that is if you are going to look within the fire. It will slightly slow down your sim to have collision but it will work and it will look accurate.

2 - COnstrain the fire and smoke emission within a void src helper, it will make sure you do not create fire and smoke anywhere outside the void src area. It will be fast but less accurate as it will not allow your smoke to be created nor visible out that predefined area, you will need to tweak it's size to make sure your smoke and fire fit in there.

3 - if you do not need to look into the fire (within the container), then reduce the height of your emitter, turn off the radial velocity and keep only the directional velocity on, and it will popo out fire and smoke only at the top of your container pointing up.

Noob's sample attached, there are other ways, but this should fix your problem.

[ATTACHMENT NOT FOUND]

Cheers,

A.

[AlFong]

Thank you, that's extremely helpful! The sample file is great for illustrating the differences among the three approaches. None of them is quite working the way I want yet, but it's definitely given me something to play around with.