System Analysis of a Gas Generator Cycle Rocket Engine

Home , Fastrac (rocket engine), HM7B, Specific impulse, Turbine blade

Technical Paper ISSN 2383-4986 International Journal of Aerospace System Engineering EISSN 2508-7169 Vo l . 6, No.2, pp.11-16 (2019) http://dx.doi.org/10.20910/IJASE.2019.6.2.11

ٻ Won Kook Cho*ˋ and Chun IL Kim** *Rocket Engine Team, Korea Aerospace Research Institute 169-84, Gwahak-ro, Yuseong-Gu, Daejeon, 34133 KOREA †E-mail:[email protected] **Department of Mechanical Engineering, University of Alberta 9211 116 St. NW, Edmonton, AB, Canada, T6G 1H9

Abstract

A system analysis program has been developed for a gas generator cycle liquid rocket engine of 30 ton class. Numerical models have been proposed for a combustor, a turbopump, a gas generator and pressure drop through a regenerative cooling system. Numerical algorithm has been validated by comparing with the published data of MC-1. The major source of error is not the numerical algorithm but the imperfect performance models of subsystems. So the precision of the program can be improved by revising the performance models using experimental data. The sea level specific impulse and vacuum specific impulse have been demonstrated for a 30 ton class gas generator engine. The optimal condition of combustor pressure and mixture ratio for specific impulse which is a typical characteristic of a gas generator cycle engine has been illustrated.

Key Words : Liquid rocket engine, Gas generator cycle, System Analysis, Optimal Condition, Specific Impulse

1. Introduction UG {G G G G G G G G G G G hG G G G G G G G G G G G G G G G G G G G G GUG{G G GG UG {G G G G G G G G G G G G G G G G G G G G G UG {G G G G G G G UG {G G G SG G SG G G G GGGG GGGGG G SGGGUG{GGGG G G G G G G G G GGGGGG G G G G G G G G G G UG pG G G SG G G G GSGGGG¡GSG G G G G G G G G G G G G SG G G UG{GG G GGGG G G G UG ~G G G G G G G G SG G G G G G G G G G SG G G G G G G G G G G G G G G G G G G ¡G G OG G ZUXG G G PUG {G G G G UG pG G SG GGGGG GG GGG GGG G G G G G G G G G G G G G G G Received: Jun. 27, 2018 Revised: Oct. 11, 2019 GUG Accepted: Oct. 15, 2019 G † Corresponding Author Tel: +82-42-860-2937, E-mail: [email protected] ⡧ The Society for Aerospace System Engineering 12 Won Kook Cho · Chun IL Kim

2. Literature survey

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