automatic combustion?

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Shrimphead
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Tue Jan 31, 2006 10:34 pm

i was thinking about pulse jets recently, and I made a connection between them and a combustion. Some pulse jets use injected propane as a fuel. So I was wondering if it would be possible for somebody to build a relatively small pulse jet, hook up a spring-mag with some really lubed up ammo and make an automatic combustion out of it. They would need a stand for the pulse jet to keep it from flying around (since it would be way too hot too hold!) Does anybody think that it's possible? I admit that it's a pretty crazy idea.
K40T1C
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Wed Feb 01, 2006 12:21 am

theoretically you could make it work but it would be extremley hard... also, I'm not sure if youve evert seen a pulse jet firing in real life, but they are EXTREMLEY loud and can be heard for miles... cops might not like that
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Shrimphead
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Wed Feb 01, 2006 12:24 am

ya I was just thinking and i realized that it was very unlikely, but I thought it would be really awesome if somebody could get it to work. I haven't actually seen a pulse jet in real life, but I do understand how loud they are and all that. I was just like "what the heck I'll see what they think"
K40T1C
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Wed Feb 01, 2006 1:08 am

also pulse jets can't operate at low speeds, because the force of the air pushes back the valve and opens it but if your not moving it would remain closed... if somehow u could pull it off though it would be very cool
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Rambo
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Wed Feb 01, 2006 1:11 am

Can some body tell me how to make a pulse jet with chaep materials from home?I have an experiance with solid fuel rockets.
K40T1C
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Wed Feb 01, 2006 1:27 am

UM... it is really complicated to try and explain how to make pulse jets, I can try to explain to u the simple theory behind them but building them is hard... they constintley need adjustment, they become extremley hot and loud, and there is no teal use for them other than bragging rights... if your still interested ill give u a couple of pointers to some sites ive found useful

a nice illustration of how hot they7 get... no that is not clear plastic... it is solid iron
Image

this website is made by a guy who has built many pulse jets and has pulsejet power boats... go karts... everything
http://www.aardvark.co.nz/pjet/howtheywork.shtml
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Brian the brain
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Wed Feb 01, 2006 5:06 am

Rambo made something that comes close...A pulse jet doesn't need a continueos spark and it suckes in it's air...but I think rambo was well on his way.
A guy called Nxi made a pneumatic engine..I think this could be driven off the barrel's excaust on Rambo's auto in turn driving a small compressor wich could provide the air intake...
In short a jet...
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Rambo
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Wed Feb 01, 2006 8:40 am

I know all of thise sites, I tried to make one but it don't want to start.Does the presure jet works on the principle of the torch?
K40T1C
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Wed Feb 01, 2006 11:52 am

I dont know very much about pressure jets... i really only know about pulse jets... and Brian... a pulse jet should never need a continous spark.... and after a while it doesnt need a spark at all...
this is because gases are elastic...when the explosion happens it shoots gas out the exahust... however it shoots to much out and it sucks some of it back in... it also sucks in new air through the front and add fuel... when the hot exhaust meets with the volatile fuel-air mixture... the cycles starts over again
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Brian the brain
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Fri Feb 03, 2006 1:24 am

I know how it works K40T1C...Read my post before you comment...sigh...
Don't call me Brian if you can't call me brain....
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dragon finder
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Sat Feb 04, 2006 3:07 pm

shriphead i have this book on how to make a reed pulse jet but it is almost high level experiance i would say medium. but the plans are simple and affective all that might me requred is a lathe and a drill press. http://www.windspire.com/jetpower/
this is where i got the plans.

p.s. free helicopter plans with order no licence needed falls under ultra-light catagory
:wink: :wink:
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