Progress Report on Preliminary Design of the LE-X Turbopump

JAXA has been conducting technology demonstration of the next generation booster engine called LE-X. The LE-X engine is a new cryogenic booster engine which has higher thrust, higher reliability and lower cost compared to the existing engines, and will be applied to the Japan’s next primary launch system. Its engine system adopts the expander-bleedcycle run on the LH2/LOX. The LE-X turbopumps, which are key components in the engine, have technical issues of developing rotordynamics with huge turbine, high turbine efficiency, high reliable rotor system and low-cost manufacturing technique. In order to clear the issues and to avoid the risks at preliminary design phase, several component tests and analysis were conducted aiming to validate the preliminary design. It appears that preliminary design of the LE-X components is successfully conducted. Feasibility of the components designs and the manufacturing process will also be confirmed in the preliminary design phase. Based on these studies, we will continue the turbopumps design of the prototype LEX engine.