We investigate the effect of steric and hydrodynamic interactions (HI) on quiescent diffusion and flow‐driven transport of finite‐sized nanoparticles through periodic 2D (two‐dimensional) and 3D (three‐dimensional) nanopost arrays using Stokesian dynamics simulations. We find that steric and HI hinder particle diffusivity under quiescent conditions and enhance longitudinal dispersion under flow. Moreover, the presence of HI leads to a power‐law increase in the longitudinal dispersion coefficient with Pe due to spatial variations in the fluid velocity. Lastly, our simulations reveal that longitudinal particle dispersion coefficients behave similarly in 2D and 3D when HI are included.

中文翻译：

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纳米粒子在多孔介质中的分散：流体动力相互作用和尺寸的影响

我们使用Stokesian动力学模拟研究了空间和流体动力相互作用（HI）对通过周期性2D（二维）和3D（三维）纳米柱阵列的有限尺寸纳米粒子的静态扩散和流驱动运输的影响。我们发现，空间和HI会在静态条件下阻碍粒子扩散，并增强流动下的纵向扩散。此外，由于流体速度的空间变化，HI的存在导致纵向弥散系数随Pe的幂律增大。最后，我们的仿真显示，当包含HI时，纵向粒子弥散系数在2D和3D中表现相似。