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Aerospace Rocket Engine Combustion Chamber Equations

  1. Sep 20, 2008 #1
    Good evening all,

    I was wondering if anyone would be able to point me in the right direction to equations in regards to designing a proper combustion chamber for a rocket engine, as well as for the throat/De Laval nozzle as well. I've looked around and I can't seem to find anything that covers the actual dimensions of the chamber.
  2. jcsd
  3. Sep 21, 2008 #2
    I don't think things are just as easy as using equations & feeding numbers for designing purpose.
  4. Sep 21, 2008 #3


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    This might be useful.


    NASA Marshall used a program called RAMP to analyze nozzle designs. I would expect Rocketdyne (now part of United Technologies/Pratt & Whitney) used their own proprietary code.

    Search Google or other search engine with "SSME","nozzle"

    The SSME uses an H2-rich mixture.

    AIAA has a number of books on propulsion, including some description of combustion chambers, throats, and nozzles.
    Last edited by a moderator: Apr 23, 2017
  5. Sep 21, 2008 #4
    Thanks, I know there are equations to make a proper combustion chamber though. I know that the chamber needs to be a certain length and diameter in relation to the nozzle.
  6. Sep 21, 2008 #5


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    One could take a cross-section and simply plot diameter or radius of nozzle as a function of distance from throat.

    For SSME -
    Area Ratio: 69:1
    Chamber Pressure: 2,994 psia
    Engine Mixture Ratio: 6.0 (IIRC, mass O2/mass H2)

    Length: 168 in.
    Diameter: 96 in.

    Last edited by a moderator: Apr 23, 2017
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