high speed moving source collisions and substeps problem

[-SeB-]

Hi,

I have a little problem with fume fx, I have a car with kind of chimney at the back and this car is moving very fast and produce lot of heavy dark smoke
but I don't find a way to have the smoke following the car nicely and going out of the chimney at the right position.
I always have hole in the smoke or the fuel, on some frame, is outside the chimney.

I have already tried with different scale scene and it doesn't fix the problem.
I also decreased the grid spacing to have better resolution, it doesn't change the problem neither.
I have tried to increase simulation substeps (1 to 50) and max iteration (200 to 400). I think this is already big values and it didn't fix the problem neither.

If someone have an idea !!

Thanks

-SeB-

[Rif]

substeps ( itterations per step ) amount will \ should help you manage and deal with theese fast moving emition \ deflection objects..

share a scene , its always better to test it ..

[-SeB-]

ok here is the scene (simplified) I'm working on

if you try you will see that the fuel is going outside of the chimney at frame 225 when the chimney start to moving.

for this simulation it takes 15 hours to simulate 60 (170 to 230) frames so you can maybe have to decrease some settings.


thanks for your help



-SeB-

[Rif]

heres a fast stab at it ..

10 sec per frame..

With an Extream movement like this , you might wanna think on Scaling the speed of the scene down .. byt half or so , and run the sim in slow mo scene and render every X frame..

just an idea.

So cubic will help you , no need for passing 5 in quality , Strides lower will gain back some details in between steps , Sensitivity of .5 or so should be enought i think , the fire i dont know why its their, cheminys are passing smokes .. and your xyz turbulance streinght is way too high ..

[-SeB-]

I can't open the scene I'm using 3dsmax 9
can you give me your settings so I can take a look
but thanks for your help

-SeB-

[Rif]

no prob..
heres the .fxp ..

ITs really just a first stab at it.. productions are all over me right now so not alot of time..