Poly-Disperse Droplet Evaporation Model

Abstract

A model for the evaporation of micron-size, poly-disperse water droplets into air has been developed that allows the prediction of droplet size distribution changes during evaporation. The model incorporates either adiabatic or isothermal boundary conditions and allows for the variation of fluid transport and thermodynamic properties during the evaporation process. The governing equations for the model are developed from the coupled mass and energy balances for the droplets and for the surrounding air assuming they are flowing along a tube and assuming diffusion mass transport and conduction heat transfer processes predominate. Droplet sizes and temperatures as well as surrounding air temperature and humidity are all output as functions of time allowing droplet lifetimes and size distribution changes to be observed. The model, at this stage, is checked against overall mass and energy balances.