Study on atomization characteristics of a kerosene jet in a supersonic crossflow

Abstract

The combustion performance of a scramjet engine is based on a two-phase mixing process of its fuel. To elucidate the mechanism of jet atomization in supersonic airflows, a numerical simulation of liquid jet atomization in a supersonic crossflow is carried out. The Euler method is used to calculate the gas phase, while the Lagrangian particle tracking method is used to calculate the liquid phase. The Reitz wave model is used to simulate the first breakup of the liquid jet, and the Kelvin-Helmholtz/Rayleigh-Taylor hybrid breakup model is used to simulate the second breakup of the droplets. The influence of the liquid/gas momentum flux ratio and the diameter of the jet on the atomization characteristics is discussed. The results show that the penetration depth increases with increasing nozzle diameter and liquid/gas momentum flux ratio. A jet with a larger liquid/gas momentum flux ratio breaks faster, and its Sauter mean diameter is smaller. The Sauter mean diameter of a droplet decreases with decreasing nozzle diameter. At 30 mm downstream of the nozzle, all jets are basically atomized, and the SMD of the jet is around 10 μm. The nozzle diameter has a greater influence on the jet penetration depth than does the liquid/gas momentum flux ratio.