憎水表面光控液滴蒸发及冷凝液滴的演化特性

• 作 者: 焦龙 陈蓉 何雪丰 朱恂 廖强
• 机 构: 重庆大学低品位能源利用技术及教育部重点实验室,重庆400030;重庆大学工程热物理研究所,重庆400030
• 出 处: 工程热物理学报
• 发表日期: 2017年3期
• 关键词: laser local heating condensed droplets dynamic evolution coalescence

实验利用可视化方法研究了憎水表面上聚焦激光局部加热作用下液滴的蒸发特性及主液滴周围冷凝液滴的生成及演化特性.波长为1550 nm的红外激光作为局部热源控制液滴的相变.结果表明:冷凝液滴随着热蒸汽在过冷基底上的冷凝而不断生长,冷凝液滴之间的聚并现象使其尺寸快速增大.冷凝液滴的演化过程受到液滴蒸发强度和冷凝持续时间的综合影响.当激光加热偏离液滴中心位置时,冷凝液滴仍然较为均匀地分布在主液滴周围.“,”In this work,the laser-induced evaporation of the sessile water droplet on the hydrophobic surface and the dynamic evolution of condensed droplets around the triple-phase contact line were visually studied.The photothermal effect of a laser with the wavelength of 1550 nm was utilized as the local heating source for generating the supersaturated vapor and controlling the formation of the condensed droplets on the substrate.It was confirmed that the condensed droplets had two distinct evolution modes:the continuous condensation of the supersaturated vapor and the coalescence between the condensed droplets.The combined effect of the evaporation of the sessile water droplet and the condensation time influences the dynamic evolution of the condensed droplets.It was also found that although the laser spot was not located at the center of the droplet,the condensed droplets were still uniformly distributed around the sessile water droplet.