Parametric Optimization of Turbopump for Reusable Rocket Engine (RRE) Applications

Abstract

With the development of contemporaneous reusable launchers, including projects such as Themis with a liquid LOX/LCH4 Prometheus engine, CALLISTO - Reusable VTVL launcher first stage demonstrator with a LOX/LH2 RSR2 engine, or Space-X’s Falcon 9 with a Merlin 1 engine, it is essential to further advance control algorithms to secure a failure-free engine operation. The engine's multi-restart capability not only implies additional requirements regarding throttling, where an extended controller-validity domain must be attained to safely reach low thrust levels for various engine operating regimes, but primarily increases the likelihood of component failure, including evolving parameters related to the mission profile. Therefore, to efficiently evaluate the fully continuous engine phases from start-up to shutdown transient, the dynamic reliability of the reusable rocket engine (RRE) is assessed along with its subcomponents under assorted failure modes, and a study based on multi-physics system-level modelling and simulation is proposed with a focus on the turbopump components. The modelling and performance analysis under transient conditions are conducted with EcosimPro ESPSS software, an object-oriented programming language. Within the presented deterministic thermically dependent structural simulation, the main control objectives pertain to end-state tracking of combustion chamber pressure and mixture ratios, along with operational constraints verification based on the LUMEN demonstrator engine and LE-5B-2 engine class. To predict the turbopump components remaining useful life, a model-based method for turbopump optimization incorporating analytical (0D) calculation is utilized.