| As NASA begins a new era of space exploration, it is recognized that a series of rocket engines will be required in order to complete object and planetary landing missions. NASA preliminary studies have indicated that a 15,000 lbf thrust LOX-methane engine with 10:1 throttling capability is a desired propulsion configuration for a Mars lander. The objective of this study is to validate a workable LOX-methane engine that is capable of a 10:1 throttling ratio for such an application. The new Mars landing engine designed herein uses components that are desired to successfully throttle the engine. A power balance model is developed, and it is determined that using an expander cycle engine with LOX-methane propellants, a pintle injector, independently driven LOX and methane turbopumps, with a thrust control valve and oxidizer control valve is a viable option for a throttleable Mars landing engine. The engine operates at a chamber pressure of 800 psia at 100% power and 80 psia at 10% power and a mixture ratio of 3.3 at both power levels. The injector is capable of achieving a ratio of Deltap/p c of 20% at all power levels. The oxidizer and fuel turbopumps generate 58.87 Hp and 170 Hp at 100% power, and 2.67 Hp and 25 Hp at 10% power respectively. |
