Experimental studies on cavitating flow for liquid rocket engine cryogenic turbopump: Review

Turbopump，which can be called the heart of engines，is a critical component of the cryogenic Liquid Rocket Engine（LRE）. The improvement of its performance is limited by cavitation conditions. Due to cavitation thermodynamic effect of cryogenic fluids，the cryogenic cavitation is far more complicated than room-temperature water cavitation. The theoretical basis and key design points of cryogenic turbopump cavitation experimental systems are introduced，and the state-of-the-art similarity criterion for the cavitation thermal effect is revealed. Then several typical cryogenic LTR turbopump cavitating flow experimental systems and investigation results are introduced in detail，it is found that the application of thermal sensitive fluids as the substitution cryogen is technology development tendency，but it is important to keep the thermal effect similarity；Developed test technologies such as optics technique and wireless data transform have been introduced into cavitating flow analysis，they are worth to develop further. At last，the theoretical modeling of the cavitation thermal effect is concluded，it is found that most published works focus on the steady cavitation performance，the theoretical modeling of unsteady cavitation characteristics have been rarely reported. This paper may provide reference for further promoting the performance and reliability of the pump-pressurizing cryogenic liquid rocket engine. © 2023 AAAS Press of Chinese Society of Aeronautics and Astronautics. All rights reserved.