The relationship between these temporal characteristics of micro-explosive breakup of water/fuel composite droplets and the ambient gas temperature

Abstract

The processes of micro-explosive breakup of water/fuel composite droplets have been actively studied recently and are used in various technological applications. However, the challenge of finding the most efficient combinations of input parameters to result in the shortest breakup delay, lowest energy consumption, and largest number of child droplets, while also allowing for generalization of experimental findings, remains unresolved. It is essential to understand how these characteristics depend on input parameters. To do this, it is important to determine the kinetic characteristics of droplet heating before micro-explosion and relate them to the properties of the liquids and heating conditions. This paper presents the micro-explosion delay times for two-liquid droplets based on experimental findings. It also presents the relationship between these temporal characteristics and the ambient gas temperature, as well as the thermal energy supplied to the droplets through various heating arrangements. The experiments were conducted using droplets consisting of water and three different types of fuel: kerosene, Diesel fuel, and rapeseed oil. The mathematical analysis of the experimental data revealed the exponential nature of the delay time of the micro-explosion with respect to temperature and heat flux. The pre-exponential factor and activation energy in the Arrhenius equation were determined after considering the influence of various factors, such as temperature, heat exchange conditions, and physical and chemical properties of the liquids and the surrounding gas. These findings confirm that micro-explosions in gas-vapor-droplet systems can occur without the risk of spontaneous ignition.