在中等德恩数下曲微流体管道中球形粒子的惯性聚焦
Inertial focusing of spherical particles in curved microfluidic ducts at moderate Dean numbers
AI总结：
研究中等德恩数下曲微流体管道中球形粒子惯性聚焦机制，分析背景流变化对惯性升力和二次流阻力的影响，揭示背景流 profile 对粒子聚焦的调控作用。
摘要：
我们研究了德恩数对曲微流体管道中悬浮球形粒子惯性聚焦的影响。先前对粒子迁移的建模假设流量足够小，使得背景流相对于德恩数的主导近似能产生合理模型。本文扩展了该模型以适用于中等德恩数（微流体学背景下）的情况，同时保持粒子雷诺数较小。这种扩展使我们能够捕捉随着流量增加而发生的背景流变化，即局部极值向外壁移动。背景流轴向速度分布的变化影响惯性升力，而横截面成分的变化直接影响二次流阻力。在保持粒子雷诺数较小的情况下，我们以类似以往研究的方式近似惯性升力，同时捕捉由于修改后的背景流分布带来的细微效应。捕捉和理解这些效应是准确建模惯性迁移的关键步骤，适用于广泛的实际应用。我们的结果揭示了背景流分布变化如何改变粒子的惯性聚焦。我们通过多种场景展示了粒子尺寸的增强横向分离，并发现聚焦时间可以大致分为两个阶段。这些结果表明，我们的模型可能有助于尺寸分离参数的选择。
英文摘要：
We examine the effect of Dean number on the inertial focusing of spherical particles suspended in flow through curved microfluidic ducts. Previous modelling of particle migration in curved ducts assumed the flow rate was small enough that a leading order approximation of the background flow with respect to the Dean number produces a reasonable model. Herein, we extend our model to situations having a moderate Dean number (in the microfluidics context) while the particle Reynolds number remains small. This extension allows us to capture changes in the background flow that occur with increasing flow rate, namely a shift in local extrema towards the outside wall. The change in the axial velocity profile of the background flow has an effect on the inertial lift force, while the change in the cross-sectional components directly affects the secondary flow drag. In keeping the particle Reynolds number small we approximate the inertial lift force in a similar manner to previous studies while capturing subtle effects do to the modified background flow profile. Capturing and understanding these effects is an important step towards accurately modelling inertial migration across a wide range of practical applications. Our results reveal how the changing background flow profile modifies the inertial focusing of particles. We illustrate enhanced lateral separation of particles by size in a number of scenarios and find that focusing times can be roughly separated into two regimes. These results suggest our model might aid with parameter choices for separation of particles by size.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
