Investigation of the pilot stagnation region in a high power liquid-fueled combustor

Particle Image Velocimetry measurements are used to investigate flow fields in liquid-fueled high thermal power density flames. The two-component velocity fields were acquired at a frequency of 5 kHz and at a spatial resolution of 9.4 pixels/mm. A piloted, partially premixed, liquid-fueled swirl burner is installed in the Purdue high pressure Aviation Combustion Experiment. The effect of pilot-to-main fuel flow splits and global equivalence ratio are studied and compared to the non-reacting dataset at the same inlet temperature and pressure. Histograms of the stagnation lines shows the evolution of the central recirculation zone as the injector's fueling is varied. The shape of the distributions elucidate the role of the pilot nozzle on the performance of the combustor.