Martel Joseph M, Toner Mehmet
Phys Fluids (1994). 2012 Mar;24(3):32001. doi: 10.1063/1.3681228. Epub 2012 Mar 6.
This report details a comprehensive study of inertial focusing dynamics and particle behavior in low aspect ratio (h/w ∼ 1/1 to 1/8) spiral microchannels. A continuum of particle streak behavior is shown with longitudinal, cross-sectional, and velocity resolution, yielding a large analyzed parameter space. The dataset is then summarized and compared to prior results from both straight microchannels and other low aspect ratio spiral microchannel designs. Breakdown of focusing into a primary and secondary fluorescent streak is observed in the lowest aspect ratio channels at high average downstream velocities. Streak movement away from the theoretically predicted near inner wall equilibrium position towards the center of the channel at high average downstream velocities is also detailed as a precursor to breakdown. State diagrams detail the overall performance of each device including values of the required channel lengths and the range of velocities over which quality focusing can be achieved.
本报告详细介绍了对低纵横比（h/w ∼ 1/1至1/8）螺旋微通道中惯性聚焦动力学和粒子行为的全面研究。通过纵向、横截面和速度分辨率展示了一系列粒子条纹行为，得出了一个庞大的分析参数空间。然后对数据集进行总结，并与来自直微通道和其他低纵横比螺旋微通道设计的先前结果进行比较。在最低纵横比通道中，在高平均下游速度下观察到聚焦分解为初级和次级荧光条纹。在高平均下游速度下，条纹从理论预测的近内壁平衡位置向通道中心移动，这也被详细描述为聚焦分解的先兆。状态图详细说明了每个装置的整体性能，包括所需通道长度的值以及可实现高质量聚焦的速度范围。
