Transport of a passive solute by surfactant-driven flows
Transport of a passive solute by surfactant-driven flows
复制标题
通过表面活性剂驱动的流传输被动溶质
DOI：
10.1016/0009-2509(94)85083-6
复制
发表时间：
1994
影响因子：
4.7
通讯作者：
J. Grotberg
中科院分区：
文献类型：
--
作者：
O. Jensen;D. Halpern;J. Grotberg
粘性薄层自由面上的非均匀浓度的局部不溶性单层，通过产生表面张力梯度，驱动剪切流，使单层扩散，引起液层自由表面的大变形。基于润滑理论，扩展了现有的表面活性剂驱动流动模型，考虑了被动溶质的输运和溶质在液层下方壁面的吸收。采用数值和平均技术相结合的方法，适用于大范围的溶质扩散系数、时间尺度和吸收速率。结果表明，溶质在液层上的扩散导致溶质的平均平流速度比表面活性剂慢，这是因为溶质被带到比表面活性剂移动更慢的区域，因为溶质被带到比自由表面上的流体移动更慢的区域，但在某些情况下，沿液层的扩散可能会盖过平流。由于液体层深度的流动引起的变形，如果发生在下边界的吸收，则以空间不均匀的方式进行。研究结果对肺部给药技术和血流显示技术具有一定的指导意义。
A localized insoluble monolayer of nonuniform concentration on the free surface of a thin viscous fluid layer will, through the generation of surface-tension gradients, drive a shear flow causing the monolayer to spread and inducing large deformations of the free surface of the liquid layer. An existing model of surfactant-driven flows, based on lubrication theory, is extended here to incorporate the transport of a passive solute and absorption of the solute at the wall beneath the liquid layer. A combination of numerical and averaging techniques are employed, appropriate to a wide range of solute diffusivities, time scales and absorption rates. It is shown that diffusion of the soluteacrossthe liquid layer causes the solute to be advected on average more slowly than the surfactant, because the solute is carried into regions moving more slowly than the surfactant, because the solute is carried into regions moving more slowly than the fluid at the free surface; diffusionalongthe layer may overwhelm advection in certain circumstances, however. Because of the flow-induced deformation of the liquid layer depth, absorption at the lower boundary, if it occurs, does so in a spatially nonuniform manner. The results have implications for techniques of pulmonary drug delivery and flow visualization.
影响因子：
3.3
作者：
OTIS, DR;JOHNSON, M;KAMM, RD
通讯作者：
KAMM, RD