基底厚度对蒸发液滴表面温度分布的影响

he temperature distribution along the surface of drying droplet has significant influences on the fluid flow and on the particle deposition of the droplet. In this paper, the effects of the substrate thickness on the temperature distribution along the droplet surface have been investigated by numerical simulations. The results show that, as the substrate thickness changes, three different states of the surface temperature distribution may appear: (1) the surface temperature increases monotonically from the center to the edge of the droplet; (2) the temperature changes non-monotonically along the droplet surface; (3) the surface temperature decreases monotonically from the center to the edge of the droplet. These patterns of the surface temperature have been explained by considering the combined effects of the heat conduction path length and the evaporative cooling. Furthermore, the "phase diagram" for the surface temperature distribution on the parameter plane (hR, θ) is obtained by calculating the surface temperature for different relative substrate thickness hR and contact angleθ. The results will be helpful to understand the droplet evaporation and provide theoretical basis for the evaporation induced self-assembly and inkjet printing.