论文标题
均质各向同性湍流中的重和轻度惯性粒子聚集体：分手和应力统计的研究
Heavy and light inertial particle aggregates in homogeneous isotropic turbulence: A study on breakup and stress statistics
论文作者
论文摘要
通过直接数值模拟研究了不可压缩，均匀和各向同性的三维湍流中惯性，固体聚集体的破裂，并通过直接的数值模拟，并通过在不同的Stokes数量和流体到特性的液体密度比率下对聚集体的Lagrangian跟踪。在Maxey-Riley-Gatignol方程的点粒子近似中，我们分析了剪切应力和阻力应力的时间序列的统计数据，在这里，这两者都被认为是负责粒子分裂的。我们观察到，不管Stokes数量如何，湍流速度梯度产生的剪切应力类似地影响了惯性和中性浮力聚集体的分裂统计，并决定了松动聚集体的分裂速率。当密度比与统一不同时，阻力应力就会占主导地位，并且被视为能够使最具耐药骨料的分解。目前的工作为包括惯性在人口平衡模型中的作用铺平了道路，这些模型解决了湍流中粒子的破裂。
The breakup of inertial, solid aggregates in an incompressible, homogeneous and isotropic three-dimensional turbulent flow is studied by means of a direct numerical simulation, and by a Lagrangian tracking of the aggregates at varying Stokes number and fluid-to-particle density ratio. Within the point-particle approximation of the Maxey-Riley-Gatignol equations of motion, we analyse the statistics of the time series of shear and drag stresses, which are here both deemed as responsible for particle breakup. We observe that, regardless of the Stokes number, the shear stresses produced by the turbulent velocity gradients similarly impact the breakup statistics of inertial and neutrally buoyant aggregates, and dictate the breakup rate of loose aggregates. When the density ratio is different from unity, drag stresses become dominant and are seen to be able to cause to breakup of also the most resistant aggregates. The present work paves the way for including the role of inertia in population balance models addressing particle breakup in turbulent flows.
