Department of Mechanical Engineering, University of Minnesota - Twin Cities, 111 Church Street Southeast, Minneapolis, MN 55455, USA.
Department of Chemical Engineering and Materials Science, University of Minnesota - Twin Cities, 421 Washington Avenue Southeast, Minneapolis, MN 55455, USA.
Philos Trans A Math Phys Eng Sci. 2023 May;381(2246):20220128. doi: 10.1098/rsta.2022.0128. Epub 2023 Mar 13.
The seminal study by G. I. Taylor (1923) has inspired generations of work in exploring and characterizing Taylor-Couette (TC) flow instabilities and laid the foundation for research of complex fluid systems requiring a controlled hydrodynamic environment. Here, TC flow with radial fluid injection is used to study the mixing dynamics of complex oil-in-water emulsions. Concentrated emulsion simulating oily bilgewater is radially injected into the annulus between rotating inner and outer cylinders, and the emulsion is allowed to disperse through the flow field. The resultant mixing dynamics are investigated, and effective intermixing coefficients are calculated through measured changes in the intensity of light reflected by the emulsion droplets in fresh and salty water. The impacts of the flow field and mixing conditions on the emulsion stability are tracked via changes in droplet size distribution (DSD), and the use of emulsified droplets as tracer particles is discussed in terms of changes in the dispersive Péclet, Capillary and Weber numbers. For oily wastewater systems, the formation of larger droplets is known to yield better separation during a water treatment process, and the final DSD observed here is found to be tunable based on salt concentration, observation time and mixing flow state in the TC cell. This article is part of the theme issue 'Taylor-Couette and related flows on the centennial of Taylor's seminal paper (Part 2)'.
G.I.泰勒（G. I. Taylor）的开创性研究（1923 年）激发了一代又一代对探索和描述泰勒-库埃特（Taylor-Couette，TC）流动不稳定性的研究，并为需要控制流体动力学环境的复杂流体系统的研究奠定了基础。在这里，使用具有径向射流的 TC 流来研究复杂的水包油乳液的混合动力学。模拟含油舱底水的浓缩乳液径向注入到旋转的内外圆柱之间的环隙中，并允许乳液通过流场分散。研究了由此产生的混合动力学，并通过测量乳液液滴在淡水和盐水中反射光的强度变化来计算有效的混合系数。通过测量液滴尺寸分布（DSD）的变化来跟踪流场和混合条件对乳液稳定性的影响，并讨论了将乳化液滴用作示踪粒子时分散的 Peclet、毛细管和韦伯数的变化。对于含油废水系统，众所周知，形成较大的液滴在水处理过程中可以更好地分离，而在这里观察到的最终 DSD 可以根据盐浓度、观察时间和 TC 单元中的混合流动状态进行调节。本文是主题为“泰勒开创性论文百年之际的泰勒-库埃特和相关流动（第 2 部分）”的一部分。
