Tracking the evaporation of binary droplets

In a new study published in the Journal of Fluid Mechanics, researchers led by Saptarshi Basu at the Department of Mechanical Engineering, IISc, have studied the evaporation of binary droplets with a non-volatile dissolved component when exposed to oscillating gas phase flow.

The key contribution of this study is the development of a theoretical relation between gas-phase frequency and the droplet velocity responsible for the modified evaporation rate. The topic and the findings of the study are of interest to a wide range of engineering and geophysical systems, including atomised fuel droplets in gas turbines and rocket engines, functional droplets in thermal spray processes, additive manufacturing and food industries, and rain droplets in clouds. Recently, it was also shown that respiratory droplets, the primary carriers of the SARS-CoV-2 virus, are also transported via unsteady flows created by respiratory events such as a cough or sneeze and ambient turbulence. In summary, the study offers deep insights into how such droplets respond, transport and evaporate in such flows.

Majee S, Saha A, Basu S, Effects of oscillating gas-phase flow on an evaporating multicomponent droplet Journal of Fluid Mechanics, 956, A17.