The Effect of Surface Temperature on Droplet Evaporation

Abstract:

Nowadays, droplets have plenty of applications in the field of microfluids, e.g. inkjet and micropump. However, some phenomena of droplets, such as the Marangoni effect, contact angle and evaporation, are not fully understood. The present paper compressively studied the effect of surface temperature on the evaporation process of droplets. Through analyzing the particle images of droplet middle plane, the effect of surface temperature on vortex flow inside the droplet and the effect of condensation process on contact line at the bottom of droplet ware illustrated. Then, the changing processes of droplet normalized volume and contact angle with time were plotted. The results show that as the decrease of surface temperature, the reducing rates of normalized volume and contact angle become slow. When the surface temperature is relatively low (e.g.5°C), droplet normalized volume and contact angle increase with time due to the condensation process.