On molar- and mass-based approaches to single component drop evaporation modelling

Different approaches to model evaporation from single-component spherical liquid drop floating in a gaseous environment are analysed. The species conservation equations in molar and mass form are solved to yield different drop evaporation models. Two of them rely on the widely used assumption of constant (molar or mass) density and yield an explicit formula for the evaporation rate, whereas the third model relieves the constant density hypothesis and yields the evaporation rate in implicit form. The comparison among the results predicted by the models is made for a relative wide range of temperature, pressure and Reynolds number operating conditions and for different liquids, like water, alcohols, ketones and hydrocarbons.