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Invention For Revolution In Transport Industry
"Sam Wormley" wrote in message ... [snipped] Excellent reply! raz |
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Invention For Revolution In Transport Industry
In sci.physics, Edward Green
wrote on 2 Aug 2003 23:18:39 -0700 : The Ghost In The Machine wrote in message ... In sci.physics, Abhi wrote on 2 Aug 2003 10:26:10 -0700 : I am Abhijit Patil, 33 serving as an Assistant with LIC of India. I have a Physics theory and based on this theory I believe, I have invention, a basic device like wheel, which can revolutionize entire transport industry on planet earth. This invention is about keeping things stationary in air by a mechanism so that these things do not fall on earth. This means, using aerodynamics and propellants, we can build vehicles to go from one place to another ... So far, so good: as in, airplane, rocket, balloon, helicopter, ultralight, air cushion vehicle, and all other variants on flying machines! Question is, why do you believe you have thought of some revolutionary method for keeping stuff airborne, never before known to man? All methods rely on differential air pressure, most further rely on reactive forces with moving air: the field is well explored. ghost in reply recovers result that name of game in low power flight is to move as much air as slowly as possible If we move 10 kg of air per second downward at .981 m/s using a wider fan, we can reduce that power expenditure to 4.811805 W. I suspect 5W is well below a turning point where we have begun burning more power in friction than in reactive thrust. And has anyone ever spoken to you about significant digits? ;-) Not significantly. :-) But you're right; I could be a little more consistent at it. ... Gossamer Albatross ... The general shape of which, as well as the bird it's name after, makes the point about moving a lot of air slowly ... big wings, slow plane, low power. That is if one wants to use as little power as possible -- which is not always the objective. For example, fighter planes which skimp on the power will probably get shot down... :-) The problem with this approach, as well as eventual dominance of friction, is incompatibility with personal transport: even if modern material permitted it, it doesn't exactly solve tranportation problems in congested areas for everybody to unfold their 30m wingspan ultralight and sail away on a song. True. (Ideally, the air would be taken from the sides of the car, not the top, and directed downward through 90 angle tubes. The reasons for this should be fairly obvious; the moving air will exert a downward pressure on the car. I'm not sure it's obvious, or even correct! Aerodynamic lift is one of those things it's possible to make about ten passes at, feel you've learned something every time, and _really_ have a handle on it this time ... and then find yourself without a clear grok of some simple sounding issue, like the one you just propose. Lift is not something we are well pre-programed to intuit -- presumably because we are not birds. There is that. I'll admit it gets weird at times, but one pass that may result in unexpected results is that the inrush of air going down is accelerated *before* the fans, but some of it deflects off, reducing the pressure on top. The pressure at the bottom increases since we're pushing air that way, and we may get a little more lift than intended -- especially if the car is near enough to the ground to allow the downwward air to bounce back up, increasing pressure still more. To do it fully right would require some sort of finite element simulator which among other things understands fluid flow. I'll have to find one... :-) A cunningly-employed kg of gasoline would generate 45 MJ and might keep me up there for a day, given a big enough and light enough fan that can move 1 metric tonne of air a second at 1 m/s or so. At least several hours anyway -- I'm picturing an ultra-light powered glider with a small motor. That would work reasonably well, yes. :-) -- #191, It's still legal to go .sigless. |
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Invention For Revolution In Transport Industry
Didn't the Yippies try this with the Pentagon in the sixties? Like, they
tried to levitate it? Don't know if they were particularly successful. |
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Invention For Revolution In Transport Industry
The Ghost In The Machine wrote in message ...
.... ... Gossamer Albatross ... The general shape of which, as well as the bird it's name after, makes the point about moving a lot of air slowly ... big wings, slow plane, low power. That is if one wants to use as little power as possible -- which is not always the objective. For example, fighter planes which skimp on the power will probably get shot down... :-) Yes, certainly. I assumed we were both considering the problem of flying with as little power as possible, to start a revolution in transport industry: that was before I realized the proposed invention was to fly with _no_ power, and I don't mean ballooning, either. .... (Ideally, the air would be taken from the sides of the car, not the top, and directed downward through 90 angle tubes. The reasons for this should be fairly obvious; the moving air will exert a downward pressure on the car. I'm not sure it's obvious, or even correct! Aerodynamic lift is one of those things it's possible to make about ten passes at, feel you've learned something every time, and _really_ have a handle on it this time ... and then find yourself without a clear grok of some simple sounding issue, like the one you just propose. Lift is not something we are well pre-programed to intuit -- presumably because we are not birds. There is that. I'll admit it gets weird at times, but one pass that may result in unexpected results is that the inrush of air going down is accelerated *before* the fans, but some of it deflects off, reducing the pressure on top. The pressure at the bottom increases since we're pushing air that way, and we may get a little more lift than intended -- especially if the car is near enough to the ground to allow the downwward air to bounce back up, increasing pressure still more. The last thing you are talking of is called "ground effect". The rest of your oracle is hard to interpret. :-) A closely related question I _have_ contemplated is the feasibility of a "suck hoverer". A suck-hoverer is a hypothetical machine which achieves lift solely by reducing over-pressure, but does not accelerate a plume of air beneath it, nor increase under-pressure (geometric sense of "under" and "over" here). Off the cuff, the smarty pants answer is "conservation of momentum says no". The answer is correct, but IMHO, the given reason insufficient. I liked that. I am a Dionysian, like Lester Zick ... I just like to think I'm usually a _correct_ Dionysian. ;-) |
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Invention For Revolution In Transport Industry
In sci.physics, Edward Green
wrote on 3 Aug 2003 17:56:29 -0700 : The Ghost In The Machine wrote in message ... ... ... Gossamer Albatross ... The general shape of which, as well as the bird it's name after, makes the point about moving a lot of air slowly ... big wings, slow plane, low power. That is if one wants to use as little power as possible -- which is not always the objective. For example, fighter planes which skimp on the power will probably get shot down... :-) Yes, certainly. I assumed we were both considering the problem of flying with as little power as possible, to start a revolution in transport industry: that was before I realized the proposed invention was to fly with _no_ power, and I don't mean ballooning, either. Yeah, well, ballooning is about the only way one can fly with no power. I'm not even sure electrostatics would work, mostly because if one throws a charged item into the air (say it has a negative charge) the negative charges in the Earth are repulsed, leaving what is essentially a positive charge. If one reverses the polarity the Earth's negative charges are attracted. Either way, the downward force appears to increase. At least with ballooning (assuming a lighter-than-air gas such as helium) one can compensate for the gravity without using energy. ... (Ideally, the air would be taken from the sides of the car, not the top, and directed downward through 90 angle tubes. The reasons for this should be fairly obvious; the moving air will exert a downward pressure on the car. I'm not sure it's obvious, or even correct! Aerodynamic lift is one of those things it's possible to make about ten passes at, feel you've learned something every time, and _really_ have a handle on it this time ... and then find yourself without a clear grok of some simple sounding issue, like the one you just propose. Lift is not something we are well pre-programed to intuit -- presumably because we are not birds. There is that. I'll admit it gets weird at times, but one pass that may result in unexpected results is that the inrush of air going down is accelerated *before* the fans, but some of it deflects off, reducing the pressure on top. The pressure at the bottom increases since we're pushing air that way, and we may get a little more lift than intended -- especially if the car is near enough to the ground to allow the downwward air to bounce back up, increasing pressure still more. The last thing you are talking of is called "ground effect". The rest of your oracle is hard to interpret. :-) Hmm...my verbiage does seem to be a bit on the confusing side, upon rereading. The idea was generally that the fans on a hypothetical "flying square" are dragging air from the top; this air, together with other air, will probably blow over the top of the "flying square", pushing it down. Or maybe not; I don't know offhand. Of course the air accelerated through the fan allows the "flying square" to stay up, as the air is given enough momentum to compensate for the "flying square"'s apparent violation of gravity. Otherwise the item would simply fall 4.905 m in 1 second to the ground (the value was to make the power computations relatively simple). A closely related question I _have_ contemplated is the feasibility of a "suck hoverer". A suck-hoverer is a hypothetical machine which achieves lift solely by reducing over-pressure, but does not accelerate a plume of air beneath it, nor increase under-pressure (geometric sense of "under" and "over" here). There is/was NASA (?) research on poking holes in an airplane wing and connecting them to a pump, to improve its characteristics. Unfortunately I forget the precise details. This looks like a variant of suck-hovering, although it doesn't appear to completely lift the wing, just get rid of some of the less desirable characteristics thereof. (Whatever they are. :-) ) Off the cuff, the smarty pants answer is "conservation of momentum says no". The answer is correct, but IMHO, the given reason insufficient. I liked that. I am a Dionysian, like Lester Zick ... I just like to think I'm usually a _correct_ Dionysian. ;-) The main problem with reducing pressure is that Nature, at least in atmosphere, abhors a vacuum.... :-) -- #191, It's still legal to go .sigless. |
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Invention For Revolution In Transport Industry
"Abhi" wrote in message m... Now the following message is being sent to people related to manufacturer in transport industry like Atlas, Hercules, Hero etc. The world will never be the same again.... Dear Sir, I am Abhijit Patil, 33 serving as an Assistant with LIC of India. I have a Physics theory and based on this theory I believe, I have invention, a basic device like wheel, which can revolutionize entire transport industry on planet earth. Well, if nothing else, I'm sure the E-mail screeners at Altlas, Hercules, Hero, etc. will welcome the slight variation on the "Nigerian business opportunity" messages that occupy the majority of their time. -Eric |
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Invention For Revolution In Transport Industry
Abhi wrote: Now the following message is being sent to people related to manufacturer in transport industry like Atlas, Hercules, Hero etc. The world will never be the same again.... Dear Sir, I am Abhijit Patil, 33 serving as an Assistant with LIC of India. I have a Physics theory and based on this theory I believe, I have invention, a basic device like wheel, which can revolutionize entire transport industry on planet earth. This invention is about keeping things stationary in air by a mechanism so that these things do not fall on earth. This means, using aerodynamics and propellants, we can build vehicles to go from one place to another faster and cheaper which ordinary man can afford. I think that Wilbur and Orville beat you to it by about 100 years. John Anderson |
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