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部分润湿液滴是适宜纳米结构表面上滴状冷凝传热的主要载体,研究纳米结构参数与部分润湿液滴合并弹跳之间的关系有重要意义,本文依据冷凝液滴生长过程中能量增加最小的原理来判断其是否为部分润湿状态,并根据液滴合并前后的体积和界面自由能守恒,确定了合并液滴的初始形状,进而对合并液滴变形过程的动力学方程进行了求解,结果表明:部分润湿冷凝液滴仅在纳米柱具有一定高度、直径间距比较大的表面上形成,而当纳米柱高度过低、直径间距比小于0.1时则形成完全润湿的冷凝液滴;液滴合并后能否弹跳与纳米结构参数紧密相关,仅在纳米柱较高、直径间距比适宜的表面上,部分润湿液滴合并后才能诱发弹跳;液滴尺度及待合并液滴间的尺度比对合并弹跳也有重要影响;多个部分润湿液滴合并后由于具有更多的过剩界面自由能而比两个液滴合并更容易诱发弹跳,本模型对纳米结构表面上冷凝液滴是否合并诱发弹跳的计算结果与绝大部分实测结果相一致,准确率达到95%。
Partially moistened droplets are suitable carriers for the droplet condensation heat transfer on the nanostructured surface. It is of great significance to study the relationship between the nanostructural parameters and the partially damped droplet coalescence. Based on the increase of energy during the growth of condensed droplets, Minimum principle to determine whether it is partially wetted state, and according to the volume before and after the merger of droplets and interface free energy conservation, to determine the initial shape of the merged droplet, and then the dynamics of the droplet deformation process was solved The results show that part of the wetting and condensing droplets are only formed on the surface of the nano-column with a certain height and relatively large diameter. When the height of the nano-column is too low and the diameter-to-pitch ratio is less than 0.1, a completely wet condensate drop Whether the bouncing can be bounced by the combination of the droplet and the nanostructure parameters is closely related to the nanostructure parameter. Only when the nanorods are taller and the pitch diameter is more suitable, Also has a significant effect on the merge bouncing; it is easier to combine multiple partial wetting drops than two drops due to having more excess interface free energy Induced bouncing, the model of condensation on the surface of the nano-structure condensation droplets induced bounce calculation results with most of the actual results, the accuracy rate of 95%.