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Aerospace Liquid Rocket Engine

  1. Jul 11, 2011 #1
    Hello,

    I'm in the process of building a small liquid rocket engine that uses glow fuel as propellant.

    Can anyone direct me to a company that sells small liquid rocket engines?

    Thank you.
     
  2. jcsd
  3. Jul 11, 2011 #2

    enigma

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    Are you looking for just the thruster, the thruster and motor, or the entire system including tanks?

    What are you planning on using as an oxidizer?

    Do you have evidence that glow fuel will work as rocket fuel?

    Liquid rockets are very non-trivial to make safely and there are ITAR issues with their sale.
     
  4. Jul 11, 2011 #3
    Not sure what you mean by thrust and motor. in general the more I can guy the less I need to design.

    Glow fuel is a muxture of ~15 oil(Castro/Synthetic), ~20% Nitomethane(CH3NO2) and the rest is Methanol(CH3OH). So there is no problem(theoretically) of using it as rocket propellant.

    Oxidezer: I'm not sure yet. Do you have any suggestions?
     
  5. Jul 11, 2011 #4

    enigma

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    The thruster is the bell shaped part that expells the gas. The motor is basically the combustion chamber. Buying parts like that run from tens to hundreds of thousands of dollars.

    Liquid rockets are nothing more than a controlled explosion. If you tinker around without planning exactly what you're doing, they're nothing more than a bomb. If the pressures in the chambers arent right, you can get burning oxidizer or fuel to backflow into a tank and explode. I highly recommend that you rethink this endeavour.
     
  6. Jul 11, 2011 #5
    Thank you for your time.
    The part you called thruster is called nozzle.

    I'm doing this as a part of a graduate course in aerospace engineering.
    So all calculations will be done.
     
  7. Jul 11, 2011 #6

    enigma

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    Your graduate school must have much better funding than mine did if they're expecting you to build a liquid fueled rocket for a class.

    Engines of this sort aren't plug &play. They would be designed specifically for the propellant mixture and thrust requirement. Unless its an industry standard you won't be able to get one of the shelf, if you could afford it.

    Again, I suggest you rethink the project.
     
  8. Jul 14, 2011 #7
    for safety measure I vote for liquid rather than solid rocket engines...atleast via a safe valve (if something goes wrong) you can put off the supply line of fuel/oxidiser
     
  9. Aug 1, 2011 #8
    What do you want to do exactly? building a liquid rocket engine using reversed engineering (just copy) or you want to do all the design by your own self?

    If the later, I think I have materials (PDF files) that could help you progressing with this project
     
  10. Aug 1, 2011 #9
    Liquid oxidizer: there is very little choice, especially among liquids that don't kill you just by reading their safety data sheet. Over time, it has boiled down to 3:

    - Liquid oxygen, the one with good performance. Cold, with associated worries. And it makes some silly jokes, like burning the metal parts if it's hot, far more so the polymer joints.

    - Nitrogen tetroxide, which is toxic. Manageable in gram quantity, big worry by the ton.

    - Hydrogen peroxide, which detonates without easily foreseen reasons.

    Then you have older choices like concentrated nitric acid, which have no clear advantage over tetroxide. Many users try to get better solutions but don't; it's a current research topic, knowing that the answers will have low performance.

    For your fuel, if you want performance, no oxygen atom should already bind to a carbon or hydrogen. An alcohol is a bad choice. A nitro-something is less bad for performance, but pure nitromethane was abandoned for rockets because boom. As you need a separate oxidizer, a good fuel is a hydrocarbon, like kerosene.

    The next big deal in liquid launchers is oxygen-methane. If you choose oxygen, methane adds little complexity, and makes a few things easier than storable liquids.

    You should look how you will cool the combustion chamber's wall. Usually done by circulating the fuel in channels, and this puts heavy constraints on the fuel. JP10 is a possibility.

    I'm a bit surprised that you plan to design or run a liquid rocket engine but ask such questions... I too suggest to read and think more before going maybe on, and only if you get much more knowledge.
     
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