Design and Validation of a Liquid Film-Cooled Hydrogen Peroxide/Kerosene Bipropellant Thruster

摘要

Thermal protection of thrust chamber wall and nozzle by employing film cooling was investigated experimentally and analytically for a hydrogen peroxide/kerosene bipropellant thruster. The thruster was designed to produce 800 N of thrust force in vacuum. Multiple injected jets of hydrogen peroxide formed a liquid film shroud that covered the inner wall of the thrust chamber and nozzle. As long as the shroud remained liquid film, the wall was protected from the heat transfer from the burnt gas in the thrust chamber. To predict the extent of the liquid film, a one-dimensional analysis model proposed by Grisson was adapted with a modification to account for the effect of thermal decomposition of hydrogen peroxide with an empirical constant K_d, determined from previous research on a similar thruster. The decomposition of hydrogen peroxide shortened the length of effective cooling with given mass flow rate of the coolant, with K_d ranging from 0.5 to 0.9, corresponding to the coolant mass flow rate estimation of 45-75 g/s. A parametric study was carried out with the coolant mass flow rate as a parameter on an 800 N bipropellant thruster specifically designed for the present study. An 800 N bipropellant thruster was designed with the coolant injectors that supplied 45-75 g/s of hydrogen peroxide.