Hydrogen Leakage Detection of Reusable Rocket Experiment Vehicle with Hydrogen/Oxygen Concentration Ratio Sensor

Abstract

In future space transportation system, concept of fault tolerant is important. Propellant leakage is one of fault modes that should be considered in the system. The space transportation vehicles could have flight environment with very little or without oxygen. Therefore, for the propellant leakage detection, gas sensors that can work without oxygen are needed. The authors have developed the gas sensor that can work without oxygen and of which output depends on the ratio of hydrogen to oxygen concentration. The present sensors were installed on a hydrogen-fueled reusable rocket experimental vehicle so that the characteristics of the sensor’s behavior was measured and evaluated though ground firing test operation of the rocket engines. Comparison of the present sensor’s behavior to that of reference sensors shows validity of the present sensor.