Detonation wave driven by aerosolized liquid RP-2 spray

Abstract

Detonation-based engines such as Rotating Detonating Engines (RDEs) have been of significant interest for aerospace propulsion. However, most detonation-related studies have focused on gaseous reactants with the majority of investigations focusing on liquid water interactions with gaseous detonations and shocks. This study explores the dynamics of detonation waves driven by aerosolized liquid fuel sprays. An unlike-doublet impinging-jet injector is used to atomize RP-2 and water into aerosolized liquid droplet cloud of measured droplet size distribution where the detonation wave interacts with the cloud mixture. Evidence of RP-2 driving the detonation phenomenon is quantified using dynamic pressure measurements and four simultaneous optical diagnostic measurements: high-speed schlieren, CH* chemiluminescence, formaldehyde planar laser-induced fluorescence (PLIF), and particle Mie scatter. The results show formaldehyde and CH* generation along with a substantial increase in pressure and wave speed when the detonation wave interacts with the RP2 mixture cloud. On the contrary, the detonation pressure and wave speed decrease are observed when the detonation wave interacts with the water droplet cloud. The investigation provides supporting information on liquid fuel droplet burning and heat release driving the detonation wave.