Journal of Bionic Engineering ›› 2023, Vol. 20 ›› Issue (3): 1132-1140.doi: 10.1007/s42235-022-00324-8
“Phase Diagram” of Surface Temperature Distribution of Sessile Droplets and the Effects of Evaporative Cooling
Chengzhi Yu1; Liran Ma2; Xuefeng Xu1; Jianbin Luo2
- 1 School of Technology, Beijing Forestry University, Beijing 100083, China 2 State Key Laboratory of Tribology in Advanced Equipment, Tsinghua University, Beijing 100084, China
“Phase Diagram” of Surface Temperature Distribution of Sessile Droplets and the Effects of Evaporative Cooling
Chengzhi Yu1; Liran Ma2; Xuefeng Xu1; Jianbin Luo2
- 1 School of Technology, Beijing Forestry University, Beijing 100083, China 2 State Key Laboratory of Tribology in Advanced Equipment, Tsinghua University, Beijing 100084, China
摘要： The temperature distribution along the surface of evaporating droplets can afect signifcantly the fow feld inside the liquid and consequently the deposition pattern on the substrate. Although a “phase diagram” for the temperature distribution along the droplet surface was revealed by the numerical simulations, its experimental verifcation has still not been reported. In this paper, the surface temperature of evaporating droplets has been observed by using an infrared (IR) camera. The experimental observations show that three diferent patterns of temperature distribution along the droplet surface occur in succession with the change of the contact angle during the evaporation process, which is in good agreement with the theoretical predictions by the “phase diagram” of the surface temperature distribution. Furthermore, the efects of evaporative cooling on the “phase diagram” of sessile droplets have been explored. The numerical results indicate that the evaporative cooling efect can alter the size of the phase regions in the “phase diagram”. These results may provide a better understanding of the evaporation process of drying sessile droplets.