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#1
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| DOE is considering a grant request for a gasoline generator prototype which could operate at about 97% efficiency. Currently the best they can do is about 65%, the rest is lost as heat. It's really very simple and low tech. It is basically an airplane gasoline motor fitted with a sliding-vane turbine on the intake, which would take advantage of the air flow created by sea level atmospheric pressure. Since this would be an airplane engine whose performance is supposed to peak at high altitudes, or at low atmospheric pressures (airplane engine manufacturers do this by simply using a specially grinded camshaft), and since my generator is supposed to work at sea level, at standard atmospheric pressure, the air flow restriction caused by the intake turbine would work to its advantage. The extra power would come from a generator attached to the intake sliding-vane turbine. -- Laurent |
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#3
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| >The requestor should be interned in guantanamo bay. Or the local loonie bin. Quent |
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#4
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| Ian Stirling wrote: Heat loss is the biggest issue, no? Could they line the cylinder walls, piston top, and valves with some sort of bakelite to keep the heat in the chamber? That would help, wouldn't it? Also, don't they lose energy in unspent gasses? Can't they put in 3 or 4 spark plugs per cylinder to make sure they burn every last drop of fuel mixture? -- ____________________________ Pear pimples for hairy fishnuts? |
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#5
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| Opus Penguin wrote: I think he was referring to the maximum efficiency out of any engine, which is (Thot-Tcold)/Thot. If you take the cold bath to be the typical environment - about 300K - then you would need an operating temperature of at least 10,000K to get 97% efficiency, even if you could somehow get a perfect Carnot cycle. I think the typical combustion energy of gasoline is around 2000K, so this sounds like a stretch. -E |
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#6
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| In article <9e32c.55898$[Only registered users see links. ].prodigy.com> , Opus Penguin <OpusPenguin@BloomCounty.nospam> wrote: The Carnot efficiency of a heat engine is (T_hot - T_cold)/T_hot. That's a theoretical maximum efficiency. You could line cylinder walls, recirculate and reheat, add spark plugs, put turbines in the exhaust, and anything else you want, and you won't beat Carnot. An engine that reaches 97% of Carnot efficiency would at least be believable. -- "The average person, during a single day, deposits in his or her underwear an amount of fecal bacteria equal to the weight of a quarter of a peanut." -- Dr. Robert Buckman, Human Wildlife, p119. |
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#7
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#8
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| "Greg Neill" <[Only registered users see links. ]> wrote in message news:Td42c.100805$[Only registered users see links. ] ... the energy make Rolls Royce are adressing converting this lost heat to power [Only registered users see links. ] Which if it works would increase the efficiency of the total system SR |
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#9
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| Laurent wrote: Hey stooopid - Second Law vs. source and sink temps for a heat engine. You are a liar, an imbecile, or a crook. Do not think of each category as being exclusive of the others. -- Uncle Al [Only registered users see links. ] [Only registered users see links. ] (Do something naughty to physics) |
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#10
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| "EjP" <[Only registered users see links. ].bad> wrote in message news:c2ag5t$r0v$[Only registered users see links. ].gov... <snip> Correct. To this I would like to add that Edison, in his search for filaments for his incandescent lamp, needed to find a material that could maintain structural integrity (i.e. it would not melt) at the highest temperature possible - because emissivity (brightness) increases rapidly with temperature (to the fourth power as I recall) and spectral characteristics of light are ideal for humans at 6000K. The best he could do was with tungsten, which melts at about 3683K. This would limit the efficiency of a real-world internal combustion engine to a little over 92%. Each percentage point gain in efficiency costs more than the previous one. Tom Davidson Richmond, VA |
| Tags |
| 97% , efficiency , gasoline , generator , rating |
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