Inertial microfluidics has been used in recent years to separate particles by size, with most efforts focusing on spiral channels with rectangular cross sections. Typically, particles of different sizes have been separated by ensuring that they occupy different equilibrium positions near the inner wall. Trapezoidal cross sections have been shown to improve separation efficiency by entraining one size of particles in Dean vortices near the outer wall and inertially focusing larger particles near the inner wall. Recently, this principle was applied to a helical channel to develop a small-footprint microfluidic device for size-based particle separation and sorting. Despite the promise of these helical devices, the effects of channel geometry and other process parameters on separation efficiency remain unexplored. In this paper, a simplified numerical model was used to estimate the effect of various geometric parameters such as channel pitch, diameter, taper angle, depth, and width on the propensity for particle separation. This study can be used to aid in the design of microfluidic devices for optimal size-based inertial particle separation.

中文翻译：

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螺旋通道中的惯性粒子分离：校准数值分析

近年来，惯性微流控技术已被用于按尺寸分离颗粒，并且大多数工作都集中在具有矩形横截面的螺旋形通道上。通常，通过确保它们在内壁附近占据不同的平衡位置来分离不同大小的粒子。梯形横截面通过在外壁附近的迪安涡旋中夹带一种尺寸的颗粒，并在内壁附近惯性地聚焦较大的颗粒，从而提高了分离效率。最近，该原理已应用于螺旋通道，以开发一种基于尺寸的颗粒分离和分选的小尺寸微流控设备。尽管有这些螺旋装置的希望，但通道几何形状和其他工艺参数对分离效率的影响仍待探索。在本文中，使用简化的数值模型来估算各种几何参数（例如通道间距，直径，锥角，深度和宽度）对颗粒分离倾向的影响。该研究可用于帮助设计微流体装置，以实现基于尺寸的最佳惯性颗粒分离。