Forced and Unforced Dynamics of a Lean Premixed Prevaporized Combustor for Civil Supersonic Transport

Several simultaneous optical and probe-based diagnostics were used to characterize the behavior of a novel lean premixed prevaporized (LPP) combustor with relevance to future commercial supersonic transport (CST) applications. The burner was tested at several fuel/air ratios while subjected to externally applied forcing. The use of fuel planar laser induced fluorescence (PLIF) revealed the stiffness of the fuel injection system to periodic oscillations within the combustor. High-speed OH* chemiluminescence and stereo particle image velocimetry were used to analyze the flow-flame coupling across different cases. Overall, the combustor exhibited no bifurcations as the fuel/air ratio and forcing frequency and amplitude were varied.