Leakage Detection in Ground Firing Test of Hydrogen-fueled Reusable Rocket with Hydrogen/Oxygen Concentration Ratio Sensor

Abstract

The authors have developed a sensor using ceria nano particles as a detection element, of which outputs depend on hydrogen/oxygen concentration ratio. That the sensor can work without oxygen is its remarkable characteristic. It has been considered that it can be applied to a space rocket that reaches a high altitude with oxygen concentration falling. Before a launch of the rocket, oxygen concentration inside of the rocket falls because inert gas is supplied to the inside of the rocket to purge oxygen and moisture. The situation of oxygen concentration falling also occurs in ground firing test of the rocket engine. The proposed sensors have been installed on an experiment vehicle with hydrogen fueled rocket engine. The sensor output data has been measured through the experiment operation such as liquid hydrogen loading and rocket engine firing in order to evaluate the characteristics of the present sensors.