论文标题
出乎意料的是缺少Marangoni对流
Unexpectedly absence of Marangoni convection in an evaporating water meniscus
论文作者
论文摘要
通常可以预期，表面张力驱动的流动在小尺度上占主导地位。在毛细血管中限制的乙醇/甲醇的弯液量发生的蒸发会引起Marangoni的对流，这是由以前的研究人员调查的。然而，在这项工作中报道的小型微通道内的蒸发水弯面条限制在小型微通道内的蒸发水弯面条中出乎意料的对流。使用共聚焦微型PIV研究了水弯面板附近的速度。水弯板是在一个充满水的微通道的尽头形成的，使弯月面暴露在大气中。蒸发水弯面液附近的流量是由毛细血管流动的综合作用引起的，以补充弯月面和由蒸发引起的温度梯度引起的浮力流量。单向毛细管流以小毛细管大小为主导，在循环浮力对流中，毛细管尺寸占主导地位。据报道，蒸发水平的流动的意外行为将有助于了解未来研究中的种族间现象。
It is usually expected that surface tension driven flow dominates at small scales. Evaporation from the meniscus of ethanol/methanol confined in a capillary induces Marangoni convection at the meniscus which has been investigated by previous researchers. However, Marangoni convection is unexpectedly absent at an evaporating water meniscus confined inside a small micro-channel which is reported in this work. The velocity near the water meniscus is studied using confocal micro-PIV. The water meniscus is formed at the end of a micro-channel filled with water keeping the meniscus exposed to atmosphere. The flow near the evaporating water meniscus is caused by combined effect of capillary flow to replenish water loss at the meniscus and buoyancy flow caused by evaporation induced temperature gradient. Unidirectional capillary flow dominates for small capillary size where as circulating buoyancy convection dominates in larger capillary size. The reported unexpected behavior of flow at the evaporating water meniscus will be helpful to understand the inter-facial phenomena in future studies.
