Anisotropic particles are common in many industrial and natural turbulent flows. When these particles are small and neutrally buoyant, they follow Lagrangian trajectories while exhibiting rich orientational dynamics from the coupling of their rotation to the velocity gradients of the turbulence field. This system has proven to be a fascinating application of the fundamental properties of velocity gradients in turbulence. When particles are not neutrally buoyant, they experience preferential concentration and very different preferential alignment than neutrally buoyant tracer particles. A vast proportion of the parameter range of anisotropic particles in turbulence is still unexplored, with most existing research focusing on the simple foundational cases of axisymmetric ellipsoids at low concentrations in homogeneous isotropic turbulence and in turbulent channel flow. Numerical simulations and experiments have recently developed a fairly comprehensive picture of alignment and rotation in these cases, and t...

中文翻译：

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湍流中的各向异性粒子

各向异性粒子在许多工业和自然湍流中很常见。当这些粒子很小且具有中性浮力时，它们会遵循拉格朗日轨迹，同时表现出从旋转耦合到湍流场速度梯度的丰富定向动力学。该系统已被证明是湍流中速度梯度基本特性的一个引人入胜的应用。当粒子不是中性浮力时，它们会经历优先浓度和与中性浮力示踪粒子非常不同的优先排列。湍流中各向异性粒子的大部分参数范围仍未探索，大多数现有研究都集中在均匀各向同性湍流和湍流通道流中低浓度轴对称椭球的简单基本情况。数值模拟和实验最近在这些情况下开发了相当全面的对齐和旋转图片，并且...