Investigation of performances of innovative aeronautic injection systems using advanced laser diagnostics

Abstract

Simultaneous measurements of Planar Laser-Induced Fluorescence (PLIF) kerosene and PLIF-OH have been successfully performed in a multipoint injection system for various overall equivalence ratios, air inlet temperatures between 480 and 730 K, and pressures up to 2.2 MPa. Single-shot two-dimensional (2D) maps of the spatial distribution of kerosene vapor and OH radical in the combustor have been recorded with good signal-to-noise ratio. Results show that depending on the split between the pilot and the main injectors, the §ame front exhibits either a single or a double structure. Good spatial correlation between the repartition of kerosene vapor and the position of the §ame front was observed; in particular, no ¤dark zone¥ is observed between the fuel and the §ame front. As temperature and pressure increase, fuel evaporation improves and the spatial distribution of OH radical becomes more homogeneous in the combustor, suggesting a partially-distributed combustion.