A methodology for particle‐resolved simulation of dense suspensions of flexible cylindrical particles in Newtonian liquid flow is described. It is based on the Lattice–Boltzmann method for solving the liquid flow and an immersed boundary method for imposing no‐slip at the particle surfaces and providing the distribution of liquid–solid interaction forces over the particle surfaces. These forces—along with contact forces—translate, rotate as well as bend the cylindrical particles. Verification tests have been performed for a single cylinder settling and deforming under gravity at a low Reynolds number. The method has been applied to a clamped flexible cylinder in microchannel flow for which experimental data are available. It then is used to investigate the behavior of hundreds of flexible cylinders with length over diameter aspect ratios of 4 and 6 in a container agitated by an impeller at a Reynolds number of 87 which implies laminar flow. The overall solids volume fraction is 15%. We study the effect of the bending stiffness of the particles on the solids suspension process, on the extent of particle deformation as well as on the torque required to spin the impeller.

中文翻译：

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悬浮在层流中的柔性圆柱体

描述了一种用于牛顿液体流中的柔性圆柱状颗粒的密集悬浮液的颗粒分辨模拟的方法。它基于用于解决液体流动的莱迪思-波尔兹曼方法和用于在颗粒表面施加无滑移并在颗粒表面上提供液-固相互作用力分布的沉浸边界方法。这些力以及接触力会平移，旋转以及弯曲圆柱形颗粒。已经针对低雷诺数下的单缸沉降和重力变形进行了验证测试。该方法已应用于微通道流动中的夹紧式柔性圆柱体，为此可获得实验数据。然后将其用于研究在叶轮搅动的容器中，长度与直径的长径比为4和6的数百个柔性圆柱的行为，其雷诺数为87，这表示层流。总固体体积分数为15％。我们研究了颗粒的弯曲刚度对固体悬浮过程，颗粒变形程度以及旋转叶轮所需扭矩的影响。