Date of Award


Document Type

Open Access

Degree Name

Bachelor of Science


Mechanical Engineering

First Advisor

Bradford Bruno




droplet, breakup, flow, models, results, engines


Secondary droplet breakup is an important topic in fluid mechanics that has applications in many atomization processes. To date, the experimental and computational research of secondary droplet breakup has focused primarily on the breakup process in flows that have steady velocities. This study utilizes computational fluid dynamics software called Star-CCM+ Version 7.04.006 to study the effects of time-varying flows on the droplet breakup process. Time-varying flows are more representative than steady flows are of the flow situations in combustion chambers of high-level engines such as jet and rocket engines. Weber number is the ratio of the external flow’s inertial forces to the droplet’s surface tension forces, and is considered one of the most important determinants of how a droplet will breakup. The relationship between critical Weber number and the ratio of the flow’s frequency to the droplet’s natural frequency will be investigated for ratio values less than, equal to, and greater than one, which highlights the effect of a flow’s frequency on the droplet breakup process. This project improved the meshing techniques of previous CFD models, validated certain numerical criteria, and developed a periodic velocity function for use in future models. This project began an investigation of two-dimensional droplet breakup and got initial results that compared well with the results of other computational studies. Future studies will expand upon these initial results and will consider the effect of the flow’s phase on the droplet’s breakup.