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Microwave beamed power
Has anybody investigated the use of microwave beamed power as a way of
eliminating the first stage of a rocket? To put it more precisely to assist a rocket by beaming microwaves to it and to use these microwaves to heat the air as it goes through a ramjet like engine. Higher up where there is no air it could heat pure hydrogen that is expelled from a tank. This would be like a solid core nuclear rocket engine but would not have any radiation nor shielding issues. I am pretty sure that large amounts of microwaves can be cheaply made with vacuum tubes and beamed up by a ground based power station. I also know they can be received by antennas and converted to DC power by diodes, but this would not be the best way in this case. We would have to heat the hydrogen somehow using the incoming microwaves. Perhaps some kind of microwave absorbing tubes could be used that can also stand high temperatures. Like some kind of ceramic coated refractory metal. Any thoughts are appreciated. Z |
#2
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zoltan wrote:
Has anybody investigated the use of microwave beamed power as a way of eliminating the first stage of a rocket? [...] You want to look to the work of Liek Myrabo. He's done too much to summarize easily in one posting, but he has looked at a large number of laser and microwave externally powered rockets and ramjets of various types. A number of his more advanced concepts are thought by other experts either to not work, or be so speculative as to functionally be science fiction. However, he also has done test flights of more nearterm practical stuff such as pulsed laser / air propelled craft using a large USAF IR laser, which amount to essentially all the actual flight test experience to date with externally powered rockets in an atmsophere. Other experts in similar areas include Jordin Kare, who is focused on laser propulsion. -george william herbert |
#3
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wrote:
[...]while producing gigawatts economically is well understood, it costs over a dollar a watt[...] It does? Then how to account for this 40 kW generator for US$13k (which comes to ~US$0.33/watt): http://www.elitegenerators.com/40qumo50.html Or these (one of which comes to ~US$0.15/watt): http://www.electricgeneratorstore.com/sppa.html Granted, a natural gas gigawatt electric power plant may indeed cost ~US$1, but clearly it doesn't have to if it isn't intended to link into a utility power grid and meet all the other requirements of said grid connection. |
#4
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Perhaps the Isp of existing LH-Lox engines could be boosted by simply
irradiating them from behind with a microwave beam. The nozzle could act as a focusing and receiving device and the water vapor in the exhaust would absorb some beam energy further improving the Isp of the rocket. The exhaust temperature could exceed conventional limitations because the center would be heated much more then the walls. Who cares what the energy costs? Zoltan |
#5
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Hydrogen is a great fuel, and so are hydrocarbons.
Gaseous hydrogen and gaseous oxygen can be entrained in a spongelike hydrocarbon aerogel and create a mixture less dense than air! By controlling the relative ratio of hydrogen and hydrocarbon gel density can be controlled over a wide range. So, imagine a very long pipe that is equipped to manufacture aerogels that entrain gaseous hydrogen/oxygen mixtures. Imagine too the pipe varies the density of the aerogel/propellant string so that the string comes to rest at various altitudes - causing the string to trace out a synergic boost curve optimal to attain LEO. Now, we create a boost vehicle with a ramjet annulus. It boosts off the launch pad achieves supersonic flight and flies into the end of the string. The vehicle ingests the aerogel propellant string - detonates it - and derives thrust from it - tracking the string as it rises. In the end we have a single stage vehicle attain orbit. Once the first vehicle is on orbit, another string can be released and rise to its given altitude - so every 15 minutes or so, we can launch another payload into space by this technique. http://www.aiaa.org/content.cfm?page...ort&gID=52 00 http://www.aiaa.org/content.cfm?page...aper&gID=21706 http://www.aiaa.org/content.cfm?page...97&g ID=23768 This is one way. Another is to use laser energy to to ablate propellant from a solid block of plastic, and then use laser energy again to detonate that plastic into CO2 and H2O - creating a controlled blast of thrust. By creating millions of points of thrust across a surface any sort of lifting and control force can be applied to that surface. http://www.aiaa.org/content.cfm?pageid=406 This is another way |
#6
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So, imagine a very long pipe that is equipped to manufacture aerogels that entrain gaseous hydrogen/oxygen mixtures. Boy, you had better hope you don't get a electrostatic discharge inside that string, or it's going to go off like a super-sized length of primacord. :-) Imagine too the pipe varies the density of the aerogel/propellant string so that the string comes to rest at various altitudes - causing the string to trace out a synergic boost curve optimal to attain LEO. Now, we create a boost vehicle with a ramjet annulus. It boosts off the launch pad achieves supersonic flight and flies into the end of the string. The vehicle ingests the aerogel propellant string - detonates it - and derives thrust from it - tracking the string as it rises. That's somewhat similar to this idea: http://www.desertsecrets.com/i.chemtrail1.jpg http://www.desertsecrets.com/5,224,663.txt A real problem would be that the propellent string could be distorted by high altitude winds into a shape that the aircraft ingesting it would have a difficult time following. Here's what happened to the smoke trail from a Minuteman missile in fairly short order due to winds at altitude: http://www.freqofnature.com/photos/mmiii/P9192028.jpg That's from this page BTW: http://www.freqofnature.com/photos/mmiii/ Pat |
#7
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In article . com,
"William Mook" wrote: Gaseous hydrogen and gaseous oxygen can be entrained in a spongelike hydrocarbon aerogel and create a mixture less dense than air! And here I've been giving my kids helium balloons that last only a week or two. Where can I get some of this lighter-than-air aerogel? ,------------------------------------------------------------------. | Joseph J. Strout Check out the Mac Web Directory: | | http://www.macwebdir.com | `------------------------------------------------------------------' |
#8
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zoltan wrote:
Has anybody investiassuminguse of microwave beamed powkineticca way of eliminating the first stage of a rocket? The Powers are just HUGE. One SSME, assuming 100% energy conversion to kinetic energy of the exhaust is about 5GW . Thats 15 GW for the space shuttle. In practice you will need a lot more than this. This is Massive. Producting that kinda power in microwaves has only been done on paper and the reality is that its unlikely to scale up as nicely as you mite like. Bottom line. Chemical rockets are not as bad as you mite think. Greg |
#9
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Pat Flannery wrote:
Here's what happened to the smoke trail from a Minuteman missile in fairly short order due to winds at altitude: http://www.freqofnature.com/photos/mmiii/P9192028.jpg That's from this page BTW: http://www.freqofnature.com/photos/mmiii/ That is some pretty fireworks show. Some pretty expensive fireworks show. |
#10
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Joe Strout wrote: In article . com, "William Mook" wrote: Gaseous hydrogen and gaseous oxygen can be entrained in a spongelike hydrocarbon aerogel and create a mixture less dense than air! And here I've been giving my kids helium balloons that last only a week or two. Where can I get some of this lighter-than-air aerogel? ,------------------------------------------------------------------. | Joseph J. Strout Check out the Mac Web Directory: | | http://www.macwebdir.com | `------------------------------------------------------------------' lighter-than-air aerogel? sounds like a good material to build aircraft from but it could become a very difficult to clean up form of litter. I wonder how pieces of it might affect jet engines or how it might feel on a windy day to have to dodge chunks of the stuff. Ken |
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