Smoke collision with fast moving self emitting object (car)

[AlSk]

Hi everybody,

 

I'm simulating smoke emitted by a fast moving car and I've encountered problems with collisions. The smoke just gets erased when the car rotates and doesn't make any evasive movement.

 

The collisions I tried were done by sourcing a collision and collisionvel field, but the behaviour isn't right.

 

I've also tried everything I've come across in the forum, but probably I've missed something:

• Higher/Lower collisionvel.
• PCG Projection
• More Substeps (Up to 9)
• Higher voxel density.
• Correct Collisions on/off

 

Maybe I have to generate the air flow manually?

 

I'd be thankful of any help or ideas.

 

A preview and the files are attached if you want to take a look.

car_steamUC_post_v0002.mp4

car_steamUC_post_v0002.zip

[evanrudefx]

I just used a collision source sop paired with static object dop and it seems to work fine. I didn't even add substeps or anything. You can see in this photo the smoke flows around the collision.

car_steamUC_post_v0002_fix.hip

Edited September 27, 2019 by ejr32123

[AlSk]

Thank you, Evan for your fast reply.

To see the effect a little bit better, I've rotated the car to land on both front fenders. I think it still cut a lot of the density.

Actually my first approach was to keep the car in place and to build a wind around it. In that setup the smoke did actually flow around quite nicely. The major backdraw was that it didn't slow down and felt like wind tunnel.