Experimental investigation of Marangoni convection in a sessile droplet at a constant heat flux condition

Abstract Droplet evaporation is a common physical phenomenon, widely used in the life, science, industry and other fields. During evaporation of the droplets, the surface tension changes due to the non-uniformity of vapor-liquid interface temperature, and the Marangoni convection is generated. Previous studies mainly focused on constant wall temperature condition, but less on constant heat fluxes condition. In this paper, a 5μl R113 sessile droplet evaporated on a hydrophilic heating surface with a constant heat flux ranging from 0~3575W/m2 was studied. A high-speed camera and an infrared camera were used to record the dynamic characteristics of the droplet evaporation phenomenon in the horizontal and vertical directions respectively. The Marangoni phenomenon of losing stability, evaporation time, the dynamic contact angle, the number of ripples, cell body diameter were present in this paper.