Droplet-Resolved Dilute Spray Evaporation Model

Abstract

A numerical model that enables the simulation of polydispersed spray behavior while allowing the resolution of droplet-scale features is described. This Lagrangian model is based on a sectional approach and captures the effect of polydispersity, droplet initial speed and direction. It is designed for flexibility in that it can be used for a variety of droplet-based processes. The model performance is illustrated using two basic configurations: spray combustion and water mist fire suppression. The spray combustion case shows how the droplet-scale resolution can be critical since phase equilibrium is controlled by droplet surface temperature, which cannot be adequately captured using a lump-parameter model. The water mist case allows a demonstration of the basic features of the spray model such as the ability to characterize the ability of smaller droplets to get close enough to a fire or a hot surface.