中文摘要：

毛细力驱动下微细通道内延展薄液膜的蒸发是很多高效热控和热沉装置的关键换热环节。借助表观接触角的演化,建立起包含固有弯月面、过渡薄液膜和平衡区三部分的延展薄液膜形状及其表面蒸发的物理数学模型,并考虑液膜的结构、工质物性和通道特征尺度,引入分离压力和毛细压力比确定液膜不同区域的范围。分析结果表明,过渡薄液膜区域占整个延展弯月面区的比例很小,但气液界面的温度变化非常明显;薄液膜过渡区对传热的主要贡献不在于增加总换热量,而是通过界面温度变化产生的Marangoni效应,对整个液膜区域的流动产生显著的＂泵吸＂作用。描述了过渡薄液膜区表面蒸发率和液膜平均速度的变化规律,发现受液膜导热热阻和分离压力产生吸附作用的综合影响,该区域的蒸发率存在局部最大值。

英文摘要：

The surface evaporation of the extended meniscus liquid film in the microchannel driven by capillary force is the key process in heat sink and thermal management equipment.The physico-mathematical model was established by considering the variation of the apparent contact angle to describe the configuration of the total extended thin film region,including the equilibrium region,the interline region and the meniscus region.In addition,the ratio of disjoining pressure and capillary pressure was introduced to distinguish the film ranges of the different regions by considering the influence of film configuration,liquid property and channel size.The results indicated that the range of the interline region was quite small in the total extended meniscus region,nevertheless the variation of its surface temperature was much obvious,implying that the resulted Marangoni effect could cause great ＂pump＂ force to drive the film flow,which may be the main contribution of the interline region to the total extended thin film evaporation.The variation of evaporating rate,and also the resulted mean velocity of liquid film in the thin film interline region were revealed,which showed that there existed a local maximum value of evaporating rate in this region by the coupled influences of decreased film thickness and adhesion force caused by the disjoining pressure.