Early-time interface instabilities in high intensity aero-breakup of liquid drop

TL;DR

This paper investigates early-time interface instabilities during high-intensity aero-breakup of a liquid drop using numerical simulations and linear-instability theory, highlighting the roles of Rayleigh-Taylor and Kelvin-Helmholtz instabilities.

Contribution

It combines simulation and theoretical analysis to identify the dominant instabilities and their origins in high Weber and Reynolds number aero-breakup.

Findings

RT and KH instabilities contribute to initial disturbances.

Disturbances originate midway from stagnation point to equator.

Modified simulations confirm the roles of KH instability.

Abstract

The early-time interface instabilities in high intensity (high Weber number and high Reynolds number) aero-breakup of a liquid drop are investigated by numerical simulations. A combined analysis based on simulation results and linear-instability theory show that both RT (Rayleigh-Taylor) and KH (Kelvin-Helmholtz) instabilities contributes the dominant disturbances originate from about the half way from the stagnation point to the equator. This is verified further with a specially modified simulation, which decreases the effect of KH instability while keeps other flow properties unchanged.