Greg, I can't really imagine it from the description. Do you have a sketch?Greg O'Bryant wrote:This is exactly what I intend to do with my pipewood( first I have to get it running). Not that much thrust, but a proof of concept project. I want to use an internal valvless pulsejet to create heat and presure waves. The pipewood is going to be inside of a larger valved duct with the tail pipe pionted toward the valves and the pipewood intake just outside of the tailpipe of the larger duct. My plan is to tune this larger duct to the pipewood. This way when the pipewood runs the larger duct will ingest more air and force it along the length of the hot pipewood until it gets to the CC which will act like a nozle for the larger duct adding heat and thrust. If----this works it should use the radient heat given off of the pulse jet to make more thrust add mass to the exhuast and quite the engine a bit.
Rocket belts and such
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Re: re: Rocket belts and such
Re: re: Rocket belts and such
http://www.technologie-entwicklung.de/G ... opter.htmlBruno Ogorelec wrote:Mark, I can't find it either...
Experience speaks more then hypothesizing ever can. More-so in chemistry.
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re: Rocket belts and such
Yes, Tom -- this is it! Thanks a lot. A flabbergasting device.
Re: re: Rocket belts and such
The original Bell Rocketbelt could fly for 13 seconds.Bruno Ogorelec wrote:Isn't the duration of thrust for a rocket simply too short? The peroxide apparatus of the original flying belt could keep a man up for a few minutes.
Today flights of 25-30 seconds are possible.
Cita
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Re: re: Rocket belts and such
Thankyou very very much Tom. Truly awesome work by the builderTom wrote:http://www.technologie-entwicklung.de/G ... opter.htmlBruno Ogorelec wrote:Mark, I can't find it either...
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re: Rocket belts and such
Bruno;
Here is a rough draft
My idea is to get as much air as possible to be forced over the hot cc while under pressure from the pulse of the pipewood. I can see that ingesting fresh air may be a problem so a side port engine like Mike's Chinese may work better. I know that finding out what pipe lengths with help it ressonate is going to be a challenge, but I am willing to try. Also if the valvles can be kept cool enough I don't see why they couldn't be made from other materials like silicone fender washers that should last a longer time. I don't know if the pulse jet can be developed too much farther, but there is no reason why you shouldn't be able to get more thrust out of them whith a little help. Any way it may be a while until I get back to working on it. Yesterday I got mild carbonmonoxide piosening from it. You know the story I was in the garage(big no no) thought I was OK right next to the open door with a breez coming in but it still wasn't enough ventilation. So just a little caution for the rest of you don't make an ass out of yourself like I did. I guess I was lucky that I never got it to sustain on it's own or I might not be here right now!
Here is a rough draft
My idea is to get as much air as possible to be forced over the hot cc while under pressure from the pulse of the pipewood. I can see that ingesting fresh air may be a problem so a side port engine like Mike's Chinese may work better. I know that finding out what pipe lengths with help it ressonate is going to be a challenge, but I am willing to try. Also if the valvles can be kept cool enough I don't see why they couldn't be made from other materials like silicone fender washers that should last a longer time. I don't know if the pulse jet can be developed too much farther, but there is no reason why you shouldn't be able to get more thrust out of them whith a little help. Any way it may be a while until I get back to working on it. Yesterday I got mild carbonmonoxide piosening from it. You know the story I was in the garage(big no no) thought I was OK right next to the open door with a breez coming in but it still wasn't enough ventilation. So just a little caution for the rest of you don't make an ass out of yourself like I did. I guess I was lucky that I never got it to sustain on it's own or I might not be here right now!
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Re: re: Rocket belts and such
The site contains a lot of other fun stuff, like the bangbox ignition device, or the microturbine, which hasn't been updated in a long time i'm sad to say...Bruno Ogorelec wrote:Yes, Tom -- this is it! Thanks a lot. A flabbergasting device.
It's funny. I always forget to bookmark that site, yet I always remember how to find it - "bangbox" on google.
Tom
Experience speaks more then hypothesizing ever can. More-so in chemistry.
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re: Rocket belts and such
An interesting site for rocket belf flying fans. Doesn't say much but the videos are very entertaining:
http://www.jetpackinternational.com/videos.html
http://www.jetpackinternational.com/videos.html
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re: Rocket belts and such
Wow Bruno those vids are are the sh@# ! Kind of hard to beleive I keep looking for the cable that he isn't hooked to!
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Well, it almost certainly isn't a hoax, as the flights are mostly very modest -- much less ambitious than those documented with older peroxide rocket belts.Greg O'Bryant wrote:Wow Bruno those vids are are the sh@# ! Kind of hard to beleive I keep looking for the cable that he isn't hooked to!
Also, the guy is cross-linked and referenced by other rocket belt builders. I presume his competitors would try to debunk him if he were a fake.
But, modest as the flights are, they are very cool indeed. The guy makes it look so easy...
Damn, I must move forward with my pulsejet belt. Whenever I see someone flying I get this strong urge to get up and make another step.
But, personal flying with some kind of a rotor above the head or below the feet is probably a more practical proposition.
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re: Rocket belts and such
While I still dream of personal flight with a Pjet, I have little hope that it will work. Doing it with raw thrust is out, you couldn't stand to be near such a thing. Doing it with a driven turbine or hero style maybe, and that's the path I'm on. Someone posted an estimate of 1 horsepower per pound of thrust if done right, so there's a shred of hope there. Throw some wings in there, then we're talking a much easier(ha!) project.
Mike Often wrong, never unsure.
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Re: re: Rocket belts and such
Man, you have to have a lot of confidence in your gear to do that. Very cool, indeed. Thanks, again, Bruno!Bruno Ogorelec wrote:Well, it almost certainly isn't a hoax, as the flights are mostly very modest -- much less ambitious than those documented with older peroxide rocket belts.Greg O'Bryant wrote:Wow Bruno those vids are are the sh@# ! Kind of hard to beleive I keep looking for the cable that he isn't hooked to!
Also, the guy is cross-linked and referenced by other rocket belt builders. I presume his competitors would try to debunk him if he were a fake.
But, modest as the flights are, they are very cool indeed. The guy makes it look so easy...
L Cottrill
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Re: re: Rocket belts and such
Right. No argument from me there. But, dreams don't die easily. I can still see this thing in my mind, roaring away.Mike Everman wrote:While I still dream of personal flight with a Pjet, I have little hope that it will work. Doing it with raw thrust is out, you couldn't stand to be near such a thing. Doing it with a driven turbine or hero style maybe, and that's the path I'm on. Someone posted an estimate of 1 horsepower per pound of thrust if done right, so there's a shred of hope there. Throw some wings in there, then we're talking a much easier(ha!) project.
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re: Rocket belts and such
Roaring is right, make you crap your pants!
Nice drawing, though!
Nice drawing, though!
Mike Often wrong, never unsure.
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Re: re: Rocket belts and such
Even worse...............Mike Everman wrote:Roaring is right, make you crap your pants!
Nice drawing, though!
The motors are likely to go into antiphase sync (alternating); the result would be, the poor pilot would be slammed alternately from each side by the pressure wave, at the cyclic rate of the motors.
Bruno, would it be possible to extend the exhaust ends of the motors downward on each side to some extent, to try and alleviate this? Not so wide overall, but deeper vertically.
Bill H.
Acoustic Propulsion Concepts
".......some day soon we'll be flying airplanes powered by pulsejets."
Acoustic Propulsion Concepts
".......some day soon we'll be flying airplanes powered by pulsejets."