Evaporation and Condensational Growth of Liquid Droplets in Nonisothermal Gas Mixtures

Abstract

A theoretical study and coupled analytical model of the growth rates of a droplet in a nonisothermal gas mixture are presented. The derived model explicitly accounts for the influence of the properties of the gaseous media on the transport processes in an aerodisperse system. The Stefan flux as well as temperature and composition dependencies of the transport coefficients are accounted for simultaneously, still resulting in a convenient analytical expression. Such an expression is especially useful to use in a numerical GDE solution routine, in which much time cannot be spent in the individual physical processes. The results of previous studies are compared to our model predictions. Numerical calculations are performed for a wide range of saturation ratios for the water droplet-humid air system and compared with experimental data. The presented new model is an improvement on the existing ones, especially in cases in which the mass transfer rates are large, resulting in a nonuniform temperature field.

Acceleration of raindrop formation due to the tangling-clustering instability in a turbulent stratified atmosphere

“…In this case the characteristic time of the decrease of droplet radius due to evaporation can be estimated using the coupled analytical model of the evaporation/growth rates of droplets (see Ref. [36]). For the ambient air temperature T a = 274 K, this model yields the following expression for the evaporation time:…”

“…(26) in Sect. IIIB, see, e.g., [36]. The droplet velocity v is determined by the equation of motion:…”

Use of Weather Variables in SARS-CoV-2 Transmission Studies

“…Exhaled viruses are encapsulated by liquid droplets, which then evaporate or grow based upon the water vapor content of the surrounding air, with the rate of evaporation increasing with increasing temperature (Nadykto et al, 2003). Droplet evaporation also depends on the velocity and dynamics of the exhaled cloud (Bourouiba, 2020).…”

A New Fine Particle Removal Technology: Cloud-Air-Purifying

“…Validation of Droplet Growth Model. Nadykto et al used the experimental method to study the particle radius as a function of time at a saturation of 1.2 and a temperature of 297.04 K. 49 On the basis of the experimental results of Nadykto, the accuracy of the model was verified.…”