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Kapelan

How to achieve correct expansion of gas after a shot

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I am trying to make a tank canon shot. The shot has to be fast with fast expansion of the gases. I set up velocity along positive X to have directional shot. In the Pyro Solver, I set Timescale = 10, Gas released about 150 in the first 5 frames with fast decreasing up to 15 by the frame 10. Then I tweaked some additional values and kind of achieved the dynamic that I wanted but I don't like one thing. At the beginning of the first 7 frames gases start to expand in all directions and then move along X axis.

Some reference images. As you can see, the flame and the gas smoke is always in front of the canon.

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You can see my result here https://streamable.com/k38dq

 

Looking at the real reference images and videos of tank's shots, you may notice that the entire amount of gases always move forward and never (partially) backwards.

So I am trying to achieve the same result: to have a cone or torus like expansion of gases in the beginning with fast advance forward of the gas.

How to get rid of this bubble like expansion and to achieve the correct behavior of the gas? I've been trying to obtain the correct result for about 2 months and still got no luck.

 

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you might wanna try to fake the expansion with a squashed-sphere shaped divergence field in front of the muzzle. Did that recently and although not 100% happy it kinda worked for my purpose

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13 hours ago, 3dome said:

you might wanna try to fake the expansion with a squashed-sphere shaped divergence field in front of the muzzle. Did that recently and although not 100% happy it kinda worked for my purpose

I did that. I used semi sphere, torus, cylinder with velocity oriented strictly along positive X axis. Each time flames and gases expand in all directions including negative X. Exception is when Timescale  and Gas released have low values and velocity has big value. In this case I get just a long stream of flames without adequate divergence.

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