Firiing tank

[Svetlin.Nikolov]

Hey all, just a quick evening test:

Simulation time: 30 mins, Render time 2h 15 mins, Xeon E5-2670.
10M cells, Unit scale = 0.02 meters, Symmetric Conservation, Q=50, Multi-pass advection, SPF=3.0, Vorticity xV = 0.5, Cooling = 0.2, Smoke dissipation = 0.05, Randomize Amount = 0.5, the rest are defaults. Default render settings too, except for External scatter boost = 0.8. The shell object velocity multiplier is 4.0. Gun discharge is 100K for 1 frame, Shell discharge is 30K to 0 in 4 frames. Ground smoke is brushed and has temperature of 270 to make it heavy (below 300).

[Paul Oblomov]

You can try to enhance ur sim
http://forums.chaosgroup.com/showthr...ool-explosions

[Svetlin.Nikolov]

Oh sure

[jstrob]

Really cool and fast result!! bravo Svetlin!

[jstrob]

Hi Svetlin. just trying to do something similar with a tank firing and at first try I don't get that fireball and huge drag for the ground smoke with PehonxFD 3. I tries to follow your settings.

For the velocity at 4 did you put it in the object properties or the source? I tried with both but still not there yet.

And when you say you used scale at 0é02, you mean your model is at right world scale and you use a 0.02 scale in the phoenix settings?

If you have to the scene around i would like to try it please.

thanks.

[jstrob]

Never mind, I got it. I just made the gun source (a cylinder inside the gun near the opening) inject volume (instead of a surface force with poly id 1) and also lower the canon a bit and play witht he shell outgoing velocity.

[Svetlin.Nikolov]

Hey,

If you want a better shockwave and one part of the simulation to affect more strongly the rest of the container, you need to use Direct Symmetric conservation (we definitely have to rename those to more humane names) and a very high quality - 50+, or even 100. Otherwise, your setup seems spot on

tank_firing.zip

Cheers!

[flipbook]

Nice work Strob!

[jstrob]

Thank svetlin. I can't show more for now but I finally simulated and rendered a cool tank shot. And now I need to launch some missiles so you can guess i'm in some kind of virtual war!

I am trying to create a shot like this at 1:41 (really nice missile launch ref by the way!)

But I have trouble getting the smoke to be projected far enough behind the missile on the few first frames. I tried with inject volume and surface force by increasing the outgoing velocity. But when I increase it too much it explodes instead of going fartgher back. should I use an external force instead?

[jstrob]

I just tried the plain force and it seems to do the trick!

[jstrob]

Why is the pain force limited to 254? finally it doesn't push far enough I will try playing with the scene scale in the phoenix dinamic settings instead.

[Svetlin.Nikolov]

Huh, seems like that's 100 inches in cm. Was supposed to be 10000, but for now you should be able to set it by script via the "strength" param. Also, as an alternative I would suggest using high outgoing velocity in surface force mode with a high number of steps per frame, because it's a fast sim and it would need those anyway.

Please share how it goes Cheers!

[jstrob]

Ok thanks good to know about the Plain force limit.

I'm using inject force and it seems ok for now. I will show you when it's published by the end of december.

[jstrob]

Hi svetlin, Is there a way to make the smoke affect the zdetph correctly? In the zdetph pass the smoke is just white.

[Ivaylo Katev]

in geometry mode it should work, but keep in mind that transparent objects do not have clear z value, because the object behind them are also visible. but if the smoke is dense enough, in geometry mode it should produce clear z pass