Abstract Particle migration in laminar boundary layers is extensively studied, but in the near-leading-edge region, this process is not fully understood, yet. In this paper, the lateral migration of heavy particles entering the laminar boundary layer near the leading edge of a flat plate is investigated. First, numerical and analytical studies show that the high-vertical-velocity zone outside the laminar boundary layer near the leading edge plays a key role in the particle's lateral migration. Then, based on the analytical result, a transverse Stokes number which accounts for the effect of the high-vertical-velocity zone and the particle's lateral inertia is proposed. Finally, results of twenty-seven simulation cases are collected and analyzed, and this number is proved to be a more suitable criterion than the Stokes number in predicting the particle's lateral migration regime near the leading edge of a flat plate.

中文翻译：

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平板前缘附近颗粒横向迁移的横向斯托克斯数

摘要 层流边界层中的粒子迁移得到了广泛的研究，但在近前缘区域，这一过程尚不完全清楚。本文研究了进入平板前缘附近层流边界层的重粒子的横向迁移。首先，数值和分析研究表明，前缘附近层流边界层外的高垂直速度区在粒子的横向迁移中起着关键作用。然后，根据分析结果，提出了一个横向斯托克斯数，该数考虑了高垂直速度区和粒子横向惯性的影响。最后对27个仿真案例的结果进行收集和分析，