Research Projects

The aerodynamic breakup of droplets in high-speed airflow is a complex phenomenon governed by several factors, including the droplet's shape, surface tension, fluid properties (liquid and gas) and aerodynamic conditions at play. While the breakup dynamics of spherical droplets have been extensively studied, the mechanisms governing the deformation and fragmentation of non-spherical droplets remain largely unexplored. This project aims to investigate the aerodynamic breakup of non-spherical droplets using advanced numerical simulations, focusing on how their aspect ratio (AR) and Weber number (We) influence breakup modes and phase boundaries. Spherical droplets typically exhibit well-documented breakup modes such as vibrational, bag, bag-stamen, multi-bag, sheet-thinning, and catastrophic. In contrast, the asymmetric shape of non-spherical droplets can introduce new complexities. The varying surface area, influenced by the aspect ratio, may result in affecting the aerodynamic forces acting on them, leading to potentially distinct deformation and breakup dynamics. Understanding these mechanisms is crucial to filling the gap in knowledge surrounding the breakup of non-spherical droplets. The study will employ interface-resolved numerical simulations using advanced computational methods, including the volume-of-fluid method, adaptive mesh refinement, and mass–momentum consistent discretization, to capture high-fidelity breakup dynamics. A rigorous validation process will be conducted against existing studies on spherical droplets, ensuring accuracy and reliability. Furthermore, detailed grid refinement studies will ensure that the simulations capture the intricate breakup phenomena without introducing unphysical artifacts at the droplet interface. A key focus of the project is the development of a comprehensive AR-We phase diagram that maps the boundaries between various breakup modes for non-spherical droplets. By systematically varying the aspect ratio and Weber number, the study aims to uncover critical insights into the deformation patterns and fragmentation thresholds unique to non-spherical droplets. These findings will provide a deeper understanding of the fundamental physics governing droplet breakup in high-speed airflow. In addition to advancing theoretical knowledge, the project will explore the deformation mechanisms and transitions between breakup modes. It will provide detailed insights into how non-spherical droplets differ from spherical droplets in terms of breakup dynamics, enriching the existing literature on droplet fragmentation. This work promises to address an important gap in fluid mechanics research by systematically investigating the underexplored area of non-spherical droplet breakup, contributing significantly to the field’s understanding of complex multiphase flow phenomena.