So I was taking a few shots of some pulsejet plume vorticies and got some interesting results.
One looks kind of like a goat sitting, licking its back.
The other one looks a lot like an angel with hands extended.
Ink blot shapes aside, they are a good visual representation of what happens behind an engine each cycle, and why augmenters work, and why they are shaped the way they are.
A little trick you can do to design a very well optimized augmenter is to fill the engine with a large charge of propane and air, and take a long exposure picture of the path the exhaust plume takes. You can see the vortex shape and path quite clearly, and its shape will literally help you define a perfect custom augmenter, no math, no generalized formulas. It will also give you a good idea of where the augmenter needs to go. Nice being able to see things that would otherwise be invisible eh?
The best way to do it is to do a number of shots, and super-impose them in a photo program, so you can average the results.
The front geometry and the expansion point are important, but the length of the expansion can vary depending on how big and heavy you want it to be. Even though the generalized augmenter formula dont perfectly apply to all engines, you can certainly see the correlation between plume, and augmenter design.
The two short fat plumes are from 8" long straight tubes, simple fireball launchers, the next from a chinese valveless.
Over fueling the duct does not really provide any more bang than the normal operational size charge, but it does fill the vorticies with burning gas for us to see.
Design a better augmenter.. No generic formulas needed.
Moderator: Mike Everman
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Re: Design a better augmenter.. No generic formulas needed.
Those are really pretty 'filamentary' pics or 'spider webs', Eric.
I'll have to see if I can do that on Linux.
I'll have to see if I can do that on Linux.
Last edited by WebPilot on Tue Mar 23, 2010 7:42 pm, edited 1 time in total.
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Re: Design a better augmenter.. No generic formulas needed.
Hi Eric
Actually I saw Jane Mansfield in the second photo
Viv
Actually I saw Jane Mansfield in the second photo
Viv
"Sometimes the lies you tell are less frightening than the loneliness you might feel if you stopped telling them" Brock Clarke
Viv's blog
Monsieur le commentaire
Viv's blog
Monsieur le commentaire
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Re: Design a better augmenter.. No generic formulas needed.
Nice wallpapers
Ray Lockwood tried it in a water tank.
Than is the way how you did it way clearer
Ray Lockwood tried it in a water tank.
Than is the way how you did it way clearer
...It's better to generate heat efficiently, than recover it efficiently...
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Re: Design a better augmenter.. No generic formulas needed.
Neet!
In the second one, I see a badger making an unsuccessful grab at a piece of toast.
This is very nice work, thanks for sharing!
In the second one, I see a badger making an unsuccessful grab at a piece of toast.
This is very nice work, thanks for sharing!
Mike Often wrong, never unsure.
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Re: Design a better augmenter.. No generic formulas needed.
Wow that's really cool. Thank you for that.
Wonder if I can capture a pic. of flame behind the tiny little things I am currently fiddling with....
Wonder if I can capture a pic. of flame behind the tiny little things I am currently fiddling with....
In the process of moving, from the glorified phone booth we had to the house we have.
No real time to work on jets, more space, no time.
Life still complicated.
No real time to work on jets, more space, no time.
Life still complicated.
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