1. Dana Lattibeaudiere February 21, 2008 Propulsion Nozzle Design Injectors Assistance from Nicole Wilcox & Stephen Bluestone AAE 450 Spring 2008

2. Nozzle Design  CEA code Addition –Pe/Pc ratio as input – varied Pc, O/F for each prop –Output parameters: c*, ɛ, γ, Tc, M, a  Assumption: –Exit Pressure = 48,263 Pa – Reason: Find ɛ AAE 450 Spring 2008

3. Injectors: AAE 450 Spring 2008 Propulsion  What are those? Who cares?  Cost:~30% of total engine cost  Recommendations: –Liquid Propellants: unlike, impinging type of injector –Hybrid Propellants: Injects ox directly down the port –91 – 93 % combustion efficiency Injects ox into a pre-combustion chamber

4. AAE 450 Spring 2008 Backup Slides Propulsion O_F3 Pc (MPa) 2.068 Ae/Atc*cfIsp_vacIspPc/PegamaMTc 5.525 2425 1.504403.7371.8 42.86 1.31012222.9842442 EXAMPLE: Selected this chamber pressure and O/F = 3 for LOX/LH2 case because there wasn’t much of a loss in Isp as Pc increased. Addition of mass is something we wanted to avoid. O_F3Pc (MPa)2.413 Ae/Atc*cfIsp_vacIspPc/PegamaMTc 6.134 2424.9 1.523406.9376.6 50 1.3131201.23.0742443 O_F3Pc (MPa)2.758 Ae/Atc*cfIsp_vacIspPc/PegamaMTc 6.718 7958 1.539409.6380.5 57.14 1.31611833.1542444

5. References  Humble, R. W., Henry, G. N., Larson, W. J., Space Propulsion Analysis and Design, McGraw-Hill, New York, NY, 1995.  Sutton, G. P., Rocket Propulsion Elements, Wiley & Sons, INC., New York, NY, 2001. AAE 450 Spring 2008