CARS temperature/multi-species measurement strategies for high speed airbreathing and rocket propulsion testing

Multicolor CARS strategies are reviewed for measurements in practical simulations of advanced propulsion systems arranged according to fuel/oxidizer type, i.e., H2-air, H2-O2, hydrocarbon-air, and hydrocarbon-O2. The measurement strategy encompasses the spectral placement of the various laser sources employed and the referencing approaches used to extract quantitative parameter values. Sample CARS measurements are presented from a hydrogen-fueled, air-fed supersonic combustor and an air-fed, hydrocarbon-fueled turboramjet combustor. The experiments were performed using a ruggedized, remotedly controlled, mobile CARS instrument configured for a single pulse (about 10 exp -8 sec) multicolor wave mixing at a 20 Hz repetition rate.