Experimental investigation of breakup times of droplet under the action of shock wave

Abstract

In this paper, the morphological characteristics and breakup time of droplet under the action of shock wave were investigated experimentally. Morphological characteristics of droplet were captured by high-speed photography. By varying the diameter of droplets and taking the influence of the shock wave Mach number into consideration, eight tests were performed in the experiments. The experimental results showed that under the action of the shock wave, the droplet underwent two different stages: the deformation stage and the atomization stage. In the deformation stage, the droplet evolved from spherical shape to pineal shape under the action of accompanying airflow induced by shock wave. In the atomization stage, the growth of unstable wave on the surface of the droplet caused by the Rayleigh–Taylor instability was the main reason for the droplet to be atomized. The effects of initial diameter and shock Mach number on atomization time were analysed. The decrease of initial diameter and the increase of shock Mach number reduced the droplet atomization time. The Mach number played a dominant role in the breakup process of the droplet.