Design of methane/oxygen fuelled bipropellant rocket engine

A revived interest in space exploration and the requirements of an actively developing commercial market have led to renewed research into the development of new rocket engines that are simpler to build; use and can operate in a wider range of conditions. One such recent development is the interest in methane (CH4) as a rocket fuel. A sub-scale rocket engine using gaseous methane and gaseous oxygen as propellants was designed, with a chamber pressure of 10 bar and mixture ratio of 3:1. A shear co-axial gas-gas fuel injector for the same engine was also designed. Numerical simulation of the performance of the complete engine was carried out. The simulation results shows that the nozzle exit Mach number and pressure close to the analytically calculated values of Mach 2.5 and 0.5 bar, and the mass fraction of methane being depleted within the combustion chamber, indicating complete combustion of the fuel. The design of the fuel injector was an area of particular focus, partly due to the absence of well-documented and validated design data and methodologies, especially for the fuels chosen.