ICSV18, Rio de Janeiro, Brazil, 10-14 July 2011 1 DYNAMIC ANALYSIS OF A LIQUID ROCKET TURBO- PUMP Bruno Ferreira Porto Institute for Advanced Studies, Division of Aerothermodynamics and Hypersonics, Rod. dos Tamoios, km 5,5 - Putim – Zip Code - 12.228-001 - São José dos Campos – São Paulo Brazil e-mail: brunofporto@gmail.com Carlos d’Andrade Souto Institute of Aeronautics and Space, Division of Integration and Testing, Praça Marechal E- duardo Gomes, 50, PO Box 12.228-904, São José dos Campos, São Paulo, Brazil. e-mail: carloscdas@iae.cta.br The use of liquid rocket engines in space launchers offer many advantages over its solid counterparts: higher specific impulse; the possibility of re-ignition in flight and the control of thrust vector magnitude. Pressurized tanks or turbo-pumps are used to inject fuel and oxidizer into the combustion chamber which pressure must be lower than the propellant lines pressure. More efficient engines require higher combustion chamber pressure and only turbo – pumps systems can provide pressures high enough to the feed lines. These systems operates at very high velocities and suffer intense dynamic loads. Therefore its rotor-dynamic behavior must be evaluated during the design stage. 1. Introduction The needs of more powerful and controllable rockets in space applications leads to liquid propelled engines. Liquid rocket engines allow the control of thrust vector magnitude and more specific impulse (a measure of engine’s efficiency given by the impulse per unit mass of propellant used) than solid propelled engines and due this characteristics become very important in the space launcher’s industry. Nevertheless, liquid engines are much more technically complex than its solid counterparts. Until now in Brazilian Space program only solid rocket motors were used. The Institute of Aeronautics and Space (IAE) is currently developing liquid rocket engines technology. The fuel and the oxidizer need to be injected into the combustion chamber at high pressures. The use of pressurized tanks is the simplest liquid feeding system but also puts short limits to the combustion chamber pressure and consequently the engine’s specific impulse. Also, tanks must be strong enough (and consequently heavy) to withstand the internal pressure necessary to expel the propellants (usually provided by some inert gas external tank). Thus, in order to obtain better performances, turbopump units (TPU) need to be used.