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Jet Hybrid

Uses a jet engine with an electric motor
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In the 60s, chrysler experimented with small, mechanically linked gas turbine engines to power cars. Probably the biggest reason they decided to trash it was the extremely slow acceleration. Now, gasoline/ electric hybrid cars are being made more fuel efficient and powerful because of torquey and relatively efficient electric motors. Why not create a gas turbine/electric hybrid? the electric motor could launch the car from a standstill and propel it until the turbine gained power. Thermoelectrics would recharge the batteries by using the great amount of heat the turbine produced, and also help to cool it. Also, turbines can run on pretty much any fuel.
acurafan07, Nov 16 2006

Chrysler turbine car http://en.wikipedia...hrysler_Turbine_Car
[jmvw, Nov 17 2006]

Variable Geometry Turbocharger http://en.wikipedia...ometry_turbocharger
[jmvw, Nov 17 2006]

[link]






       There was a propane-powered turbine/electric hybrid around a few years ago, as a one-off test/demo vehicle. It worked pretty well, IIRC, but I'm not googling for it.   

       The jet-engined cars had slow acceleration because the drivers would engage the clutch, then advance the throttle. It has been often pointed out since that they should have advanced the throttle first, then engaged the clutch.
baconbrain, Nov 16 2006
  

       Holy Cow! 60,000 RPM. It looks like the 70's fuel shortages might have also helped to end development on this engine.
Zimmy, Nov 16 2006
  

       Spool up time for a jet is slow so in order to make the cars respons in traffic even close to what we now get you would have to operate the engine at high rpms. Not great for fuel econ.. and the clutch would be fun to design. i know of at least one very large ship that uses just this sort of power plant configuration though. But the response time is only average (for a ship)
Willlie, Nov 16 2006
  

       Thats better! (+)
jhomrighaus, Nov 16 2006
  

       There are modern turbo compressors with variable geometry (such as Garrett VNT - see link). Perhaps the same technology can be used in gas turbines also, so the system could run at more or less constant rpm and even idle at high rpm. You could then use an electric motor or.. CVT to match constant engine speed, but variable output power of the turbine to varying road speed.
jmvw, Nov 16 2006
  

       To accelerate the vehicle more quickly, you simply depress the throttle pedal for a few seconds before you release the brake pedal.
BJS, Nov 17 2006
  

       Are we talking about a jet engine, generating thrust, or a gas turbine engine, connected to a gearbox?
Texticle, Nov 17 2006
  

       The Chrysler car had a gas turbine that drove a gearbox (link), I assume this is what is meant.
jmvw, Nov 17 2006
  

       Yes sorry i meant gas turbine... Jet just sounded cooler.
acurafan07, Nov 17 2006
  

       Thermocouples would be a lousy way to provide electricity. It would be better to just put a generator on the output shaft of the turbine and use that to power the hybrid system.   

       A more cost effective turbine might be a Tesla turbine. You also might consider using a hydrostatic hybrid system, with the energy stored in pressurized hydraulic fluid instead of batteries.   

       I think the real reason that the turbine cars were abandoned was because they were too expensive to make and weren't very efficient. The reason they were unresponsive was because the engine is essentially one big flywheel. And I don't think there was any clutch, since the power turbine acted as a torque converter.
discontinuuity, Nov 17 2006
  

       //The reason they were unresponsive was because the engine is essentially one big flywheel//   

       This is why I suggested running at constant rpm with variable geometry.   

       I thought gas turbines can be more efficient then piston engines? Wikipedia shows a turbine that gets 60% thermal efficiency in a combined cycle.
jmvw, Nov 17 2006
  
      
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