Evaporation Kinetics and Residue Patterns of a Nanofluid Droplet

This paper studies how the nanoparticle size affects nanofluid droplet evaporation kinetics and residue patterns. An experiment is set up to investigate the evaporation rate of a sessile nanofluid droplet under ambient conditions using different particle sizes, with diameters of 9nm, 13nm, 20nm, 80nm and 135nm. The smaller the particle size, the higher the evaporation rate of the nanofluid droplet. After evaporation, a residue pattern is left on a substrate. The experiment shows that different particle sizes and concentrations have various residue patterns. For smaller size particles (diameters up to 13nm), a ring-shaped pattern is observed after evaporation. A uniform pattern appears for particles bigger than 13nm.