Real Time, Non-intrusive Detection of Liquid Nitrogen in Liquid Oxygen (LOX) at High Pressure and High Flow

SSC needs the sensors that are capable and can be operated in liquid oxygen (LOX) and or liquid hydrogen (LH2) cryogenic environment to improve SSC cryogenic testing. In particular, the Stennis Space Center (SSC) would like to develop a sensor to monitor the quality of LOX in the delivery line during the testing of a rocket engine. Spontaneous Raman scattering (SRS) with its relative simplicity and multi-molecule analysis can be easily employed to develop a sensor for on-line, real-time measurement. The goal of the proposed effort is to develop a SRS sensor, which is able to provide sub-millisecond sampling time for detecting nitrogen percent concentration in cryogenic propellants. During Phase I, a SRS system based on photo multiplier tube detection will be designed. The experimental parameters will be evaluated to achieve optimum response time and sensitivity. A prototype will be delivered to NASA/SSC at the end of Phase I. The study from Phase I will provide the necessary information to improve the phase II prototype design to achieve sub millisecond response time and better sensitivity. In Phase II, a prototype SRS system will be developed and tested at SSC and will be delivered to NASA/SSC for on line measurement