High Frequency Combustion Instability Studies of LOX/Methane Fueled Rocket Engines

摘要

A series of studies were conducted using a rectangular rocket chamber burning LOX methane propellanrs to investigate the effect of the temperature of the methane on the lunation of combustion instability The rectangular rocket used in these studies employed LOX centered coaxial swirl injectors The rectangular injector used in these studied provided 16 possible injector element locations in a linear array. Variation of injector element location showed that injector elements placed near the pressure anti-node of the first transverse acoustic mode of the chamber resulted in higher pressure oscillations than injector elements located near the pressure node of this mode. The methane propellant temperature varied over a Temperature range from - 70 to -100 deg F (-56 to -73 deg C) for the cooled studies and from -6 to +40 deg F (-21 to +4 deg C) for the ambient temperature studies The results obtained from monitoring the pressure oscillations using high-speed pressure transducers indicated no difference between the cooled methane test cases as compared to the ambient temperature test cases.