Effect of aluminum nanoparticles addition on the evaporation of a monodisperse ethanol droplet stream

Abstract

Evaporation behavior of nanofluid droplets within a fuel cloud plays an important role in most applications. Reported here is an experimental study on the evaporation characteristics of a monodisperse droplet stream of pure ethanol containing aluminum nanoparticles with varying concentrations (up to 0.3 wt.%) at different environmental temperatures (296–743 K). The recently developed phase rainbow refractometry (PRR) is used to simultaneously measure droplet temperature, size, and size variation of nanoscale. The results show that droplet evaporation under the experimental conditions still follows the classical D2-law. Furthermore, the addition of aluminum nanoparticles gradually decreases the evaporation rate. And a 16.2% reduction in the evaporation rate constant is observed when n-Al concentration increases to 0.3 wt.%. The effect of interactions between droplets on evaporation is quantified by combining with isolated droplet evaporation constant predicted by the theoretical model. And the quantified interaction effect is compared with the proposed empirical correlation, indicating that the interaction effect on the evaporation is similar for the studied range of n-Al concentration.