Atomization of liquid pulsed jet in subsonic crossflow

Pulsed jet is an effective solution to improve fuel jet penetration depth and consequently increase the mixing efficiency of gas-liquid in conventional combustion chambers. This has the benefits of reducing pollutant emissions and diminishing the instability of fuel combustion. However, the atomization process of pulsed jets with small amplitude has still not been properly investigated. This paper studies such a process through Large Eddy Simulation and a Coupled Level Set and Volume of Fluid method. We investigate the atomization process in a liquid pulsed jet with a subsonic crossflow and the impact of the Strouhal number on atomization morphology and the behavior of the pulsed jet in general. Results show that, with a constant mass flow rate, the role of Rayleigh-Taylor instability is replaced by the periodic fluctuation of the jet velocity, which ends up dominating the primary process of atomization of the liquid transverse pulsed jet. This also improves atomization, in general, and the fragmentation of the jet. We also show that the Strouhal number significantly impacts the penetration depth of the jet, with high values increasing penetration by up to 12%.