Dynamic Response Analysis of High-Pressure Rocket Pumps

With regard to the development of a liquid-fuel rocket engine, knowledge of unsteady characteristics of turbopumps is essential in attempts to increase rocket reliability. Numerical simulation is very advantageous in determining the unsteady characteristics of turbopumps, and knowledge thus obtained can contribute to decreasing the cost and the number of experiments. In the present study, the effect of compressibility of cryogenic propellants, such as liquid hydrogen (LH2) and liquid oxygen (LOX), and the effect of nonlinearity of flow on the dynamic response of a high-pressure turbopump were considered. The results of calculation were compared with a nonlinear incompressible mathematical model. The effects of dynamic characteristics of a cavitating inducer, such as cavitation compliance and mass flow gain factor, as well as the effect of pipe elasticity and that of an accumulator for the POGO suppressor, were also analyzed.