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SpaceX's New Combustion Technologies

Posted by samzenpus on from the try-this-one dept.

An anonymous reader shares this story that takes a look at some of the advances SpaceX is working on. "Getting a small group of human beings to Mars and back is no easy task, we learned at the recent GPU Technology Conference in San Jose hosted graphics chip and accelerator maker Nvidia. One of the problems with such a mission is that you need a very large and efficient rocket engine to get the amount of material into orbit for the mission, explained Adam Lichtl, who is director of research at SpaceX and who with a team of a few dozen programmers is try to crack the particularly difficult task of better simulating the combustion inside of a rocket engine. You need a large engine to shorten the trip to Mars, too....Not only do you need a lot of stuff to get to Mars and sustain a colony there, but you also need a way to generate fuel on Mars to come back to Earth. All of these factors affect the design of the rocket engine....As if these were not problems enough, there is another really big issue. The computational fluid dynamics, or CFD, software that is used to simulate the movement of fluids and gases and their ignition inside of all kinds of engines is particularly bad at assisting in rocket engine design. 'Methane is a fairly simple hydrocarbon that is perfectly good as a fuel,' Lichtl said. 'The challenge here is to design an engine that works efficiently with such a compound. But rocket engine CFD is hard. Really hard.'"

3 of 132 comments (clear)

  1. Wrong Focus by sycodon · · Score: 3, Insightful

    It's time to stop jetting around the solar system on chemical rockets. Designers and funding should be directed towards lofting and running multi-megawatt reactors. They would be used to power multiple ION engines and once at the destination, provide power.

    --
    When Fascism comes to America, it will call itself Anti-Fascism, and tell you to give up your guns.
    1. Re:Wrong Focus by itzly · · Score: 4, Insightful

      You cannot leave earth or mars surface using an ion engine.

    2. Re:Wrong Focus by nojayuk · · Score: 3, Insightful

      A NTR requires the reactor core to be hotter than the exhaust gas stream/propellant in order to transfer heat to it. Anything over 4000 deg K, structures in the core are going to melt and that would be bad, and that limits how hot and how fast the exhaust will be.

      Nuclear thermal is more efficient than chemical rockets but not that much more efficient. It can use readily available mass like cometary or asteroidal ice or gases like methane mined from Titan but if you have access to such sources then simple cryogenic fuel/oxidiser combos like LOX/LH2 produced from ice by solar-powered electrolytic plants are going to be easier to manage and less massive than a reactor-based rocket motor. In such a case the vacuum of space works to your advantage to keep the LOX and LH2 from boiling off too fast.