Where do I change the "emission rate?" in my smoke trail

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bguchte
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Hi all,

I have a question about Pyro FX, smoke trail shelf tool. I added it to my object and it work very nice. The only thing is that the trail that gets emitted from my object is not continues. It's like every frame it emits smoke from the object but it doesn't have continuity. I don't know how to explain it well. I attached an image to this post were you can see it more clearly. What do I need to do to change this?

Thanks

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Hoduini.png (422.9 KB)

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You don't see continuous emission because of the speed in the .abc file. Your mesh source moves so fast that it produces gaps between frames.

One way to handle fast moving emitters (particles, pyro and fluid) is to remove all translation data and simulate at the origin. You can still supply the source velocity. After the simulation is cached or complete, copy the result to the center point of the moving bounding box of the original source.

This can keep your smoke domain, smaller, and avoid complicated clustering setups.
Edited by Enivob - July 7, 2019 13:41:19

Attachments:
ap_tire_particles_070719.hiplc (1.0 MB)
tire_smoke.gif (1.2 MB)
wheels_2.abc (5.9 MB)

Using Houdini Indie
Ubuntu 18.04 48GB Ryzen 16 core.
nVidia 1070GTX 8BG RAM
bguchte
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Enivob
You don't see continues emission because of the stepping in the .abc file. Your mesh source moves so fast that it produces gaps between frames.

One way to handle fast moving emitters (particles, pyro and fluid) is to remove all translation data and simulate at the origin. You can still supply the source velocity. After the simulation, copy the result to the center point of the moving bounding box of the original source.

This can keep your smoke domain, smaller, and avoid complicated clustering setups.


Oh wow thank you so much for your help! I'm analyzing it node by node now to see what you did. I don't know what you realy mean with copying the simulated result to the original source but this already helps alot thanks
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You can leverage the center point of the bounding box technique to copy a standard particle emitter to the back of the wheels. You'll immediately notice the gap problem, again. To get around this, blast the particles out very fast in the direction of the gap and make their life very short. Then use the Z-axis variation, on the Attributes tab, to spread out the particles, even more to erase the gap.

Once you have particles, you can make smoke that follow the vehicle, in case you need a far away establishing shot. The Dissipation slider, on the pyrosolver can be used to control the smoke length. Turn it up to remove density quicker.
Edited by Enivob - July 7, 2019 12:51:29

Attachments:
ap_tire_particles_070719.hiplc (1.4 MB)
tire_smoke.gif (117.1 KB)

Using Houdini Indie
Ubuntu 18.04 48GB Ryzen 16 core.
nVidia 1070GTX 8BG RAM
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