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Quad Thrust Fuel Transit Drive

  1. Aug 24, 2011 #1
    First of all this is not a perpetual motion machine and is not the previous U Reusable Fuel Transit Drive I designed earlier. This type of transit drive, which doesn't reuse fuel, works in theory by having two combustion chambers and their respective exhaust nozzles positioned parallel to the spacecraft's length and perpendicular to its width. Fuel is pumped into the combustion chambers and goes out the two exhaust nozzles at high velocity (the fuel exhausts push the ship forwards when they hit the bulkhead positioned at the fore part of the combustion chambers which is forces 1 and when they exit through the exhuast nozzles which is forces 2), and each fuel exhuast half next travels through a C shaped loop (which is forces 3 & 4 that cancel each other and forces 5) around nearest combustion chamber and then each fuel exhaust travels through its respective symmetrically backwards C shaped loop (which is forces 6 - forces 5 & 6 cancel each other and forces 7 & 8 that cancel each other) until both fuel exhausts hits the ship's bulkhead (forces 9) pushing it more forwards (that bulkhead is parallel to the ship's width and perpendicular to its length). The fuel exhausts don't exit the spacecraft. The structure of the tunnels, combustion chambers, exhaust nozzles, etc. are made up of a theorized new super element I call superglass (the superglass structure negates the necessity of magnetic fields to contain the fuel exhaust particles to keep them from melting spacecraft structure). You'll note that I didn't describe pushing fuel exhausts back into the combustion chambers along the ship's width when they're at forces 9 to become forces 1 again to design this quad thrust fuel transit drive as a perpetual motion machine.
    Last edited: Aug 24, 2011
  2. jcsd
  3. Aug 24, 2011 #2


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    I think that the fuel has to be accelerated again after they hit the fore bulkhead. Looks like a complicated way of burning fuel with no gain to me.
  4. Aug 24, 2011 #3


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    I think I know what you're getting at, and it won't work. But you might want to draw a picture, labeling all of the forces and important points, so that we can tell you exactly why.
  5. Aug 24, 2011 #4


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    If it's a closed system free of any external forces, then the center of mass of the system can not be accelerated.
  6. Aug 26, 2011 #5
    I have no way of drawing a picture except for an ASCII diagram. What you should do is quote each part of my original message and explain why those forces won't cause acceleration. I can quote your quotes and explain any inability to comprehend my first post in this topic. Think of both of the loops as each being cut at the aft part and those end pieces bent towards and connected to the midship bulkhead.
  7. Aug 26, 2011 #6

    Vanadium 50

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    rcgldr gave the correct answer.

    We do not discuss perpetual motion machines on PF, even if someone starts with "this is not a perpetual motion machine".
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