Unstable invasion of sedimenting granular suspensions

垂直壁面附近沉降悬浮液的分析

Analysis of a sedimenting suspension near a vertical wall

本文研究垂直壁面附近Stokes流沉降悬浮液，证明壁面贫颗粒层对主体动力学的影响可由Navier型壁面定律描述，从而严格解释实验中的表观滑移，并讨论本征对流。

Hyperuniformity with no fine tuning in sheared sedimenting suspensions

Particle suspensions, present in many natural and industrial settings, typically contain aggregates or other microstructures that can complicate macroscopic flow behaviors and damage processing equipment. Recent work found that applying uniform periodic shear near a critical transition can reduce fluctuations in the particle concentration across all length scales, leading to a hyperuniform state. However, this strategy for homogenization requires fine tuning of the strain amplitude. Here we show that in a model of sedimenting particles under periodic shear, there is a well-defined regime at lo…

沉降悬浮液中回流诱导的速度波动惯性停滞

Backflow-Induced Inertial Arrest of Velocity Fluctuations in Sedimenting Suspensions

该研究提出自洽流体动力学理论，揭示回流诱导惯性屏蔽抑制沉降悬浮液速度波动发散，预测标度律 prefactors 并吻合实验，捕捉关联 regime 与系统 regime 的 crossover。

Hydrodynamic simulations of sedimenting dilute particle suspensions under repulsive DLVO interactions

We present guidelines to estimate the effect of electrostatic repulsion in sedimenting dilute particle suspensions. Our results are based on combined Langevin dynamics and lattice Boltzmann simulations for a range of particle radii, Debye lengths and particle concentrations. They show a simple relationship between the slope $K$ of the concentration-dependent sedimentation velocity and the range $χ$ of the electrostatic repulsion normalized by the average particle-particle distance. When $χ\to 0$, the particles are too far away from each other to interact electrostatically and $K=6.55$ as predi…

Representative subsampling of sedimenting blood

It is often necessary to extract a small amount of a suspension, such as blood, from a larger sample of the same material for the purposes of diagnostics, testing or imaging. A practical challenge is that blood sediments noticeably on the time scale of a few minutes, making a representative subsampling of the original sample challenging. Guided by experimental data, we develop a Kynch sedimentation model to discuss design considerations that ensure a representative subsampling of blood for the entire range of physiologically relevant hematocrit over a specified time of interest. Additionally, …

沉降纤维悬浮液中速度波动的动力学

Dynamics of the velocity fluctuations in sedimenting suspensions of rigid fibres

研究沉降纤维悬浮液中速度波动的动力学，揭示高伽利略数和低浓度下纤维聚集体的形成及流体各向异性特征。