A Numerical Study of Droplet Evaporation and Combustion in the Presence of an Oscillating Flow

Abstract

The two-dimensional, unsteady, laminar conservation equations for mass, momentum, energy, and species transport in the gas phase are solved numerically in spherical coordinates in order to study heat and mass transfer, and combustion around a single spherical droplet. The droplet mass, momentum, and energy equations are also solved simultaneously with the gas phase equations in order to investigate the effects of droplet entrainment and heating in the oscillating flow with and without a steady velocity. The numerical solution for the case of single droplet combustion gives the droplet diameter and temperature variation as well as the gas phase velocity, temperature, and species concentrations as a function of time. The effects of frequency, amplitude of oscillating flow, and velocity ratio of oscillating flow amplitude to the steady velocity on droplet combustion are also investigated. The droplet burning history is not governed by the d2-law in the presence of oscillating flow, unlike the case of quiescent ambient conditions.