Numerical Simulation of Atomization Characteristics of Kerosene Under Aircraft High-Altitude Conditions

Abstract

The atomization characteristics of kerosene after aircraft engine flameout before trying high-altitude relight is important. In this study, the influences of flight altitude and Mach number on droplet-size distribution, droplet temperature, probability density function and uniformity were investigated by numerical simulation. After aircraft engine flameout, the increase of the intake air flowrate by decreasing flight altitude broadens the vortex core region of combustion chamber, it improves droplet secondary atomization and the uniformity, and kerosene droplet diameter decreases from 69 μm to 47 μm when flight altitude decreases from 10 km to 5 km at Ma=0.7. Increasing the flight Mach number not only reduces kerosene droplet size, but also makes the droplet distribution more uniform. The aerodynamic Weber number increases with the increase of flight Mach number, and droplet is more easily broken into small droplets at Ma=0.7-0.9. Kerosene droplet diameter decreases from 87 μm to 37 μm when flight Mach number increases from 0.4 to 0.9 at H=7 km, and this improves kerosene atomization for high-altitude relight.

Keywords: Atomization, Kerosene droplet, High-altitude relight, Mach number, Flight altitude