Using Phoenix to simulate a gas cloud

[Ivaylo Katev]

everything seems right, attach the scene to see what's wrong

[magarlick]

Ok, scene attached. Thanks a lot.

[Svetlozar Draganov]

Here is one example without script:
https://www.dropbox.com/s/f8fxfgv1by...lackhole04.max

A cylindrical objects is animated and used as additional source objects with activated temperature=1, smoke=1 and velocity=0.25

[Ivaylo Katev]

well, i found the following mistakes:
- you are using the source intended for the black hole, this source is negative, it does not produce matted, but eats it create your own source with positive discharge
- the interaction list is set to exclude by default
- the cylinder must be rotated in order to produce a jet in the simulator's plane
so, follow this:
- open the original scene
- create a new source
- set discharge=50, temperature=1,smoke=1, polygon id=1
- create cylinder and rotate it so that the top of the cylinder to be toward the desired velocity of the cloud
- select the cylinder in the source

[magarlick]

ok, thanks, I now have got it working. Sorry for my mistakes! The trouble now is that it looks nothing like your original simulation. The jet comes out in a continuous stream. So I animated it so that the source discharge goes to 0 after ten frames, but still some stuff comes out of the source after frame 10, in a thinner stream.

Also the flow is smooth and lacks the vorticity of your original model, even though I have kept the vorticity at 0.1, your initial value.

Scene attached so you can see what I mean.

[magarlick]

Thank you. I would like to see this file but unfortunately I can't open it. Max just gives me a file error: 'open failed'. I am using Max 2013 on a PC.

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Added later: Sorry, I was trying to open the file in an older version of Max, which I thought I had uninstalled. It works now.

[Ivaylo Katev]

well, this issue is well known, the sources with zero discharge still produce liquid, smoke and whatever, because the diffusion.
to avoid this, animate the temperature to reach zero one frame before the discharge reaches zero, or just move the geometry after its work is done.
about the vorticity, when you simulate liquids the vorticity is switched off. however the simulation is 2d, tat allows very big resolution of the grid, just keep your advection to be multipass, and the vorticity will appear.