We advance a quantitative description of the critical shear rate γ̇c needed to dislodge a spherical particle resting on a surface with a model asperity in laminar and turbulent fluid flows. We have built a cone-plane experimental apparatus which enables measurement of γ̇c over a wide range of particle Reynolds number Rep from 10−3 to 1.5 × 103. The condition to dislodge the particle is found to b...

Microfluidic techniques are effective tools for precise manipulation of particles and cells, whose enrichment and separation is crucial for a wide range of applications in biology, medicine, and chemistry. Recently, lateral particle migration induced by the intrinsic hydrodynamic effects in microchannels, such as inertia and elasticity, has shown its promise for high-throughput and label-free p...

In this work, the particle size distribution measured using the dynamic light scattering (DLS) technique is compared with that obtained from the static light scattering (SLS) technique or provided by the supplier measured using the Transmission Electron Microscopy (TEM) technique for dilute Poly(N-isopropylacrylamide) microgel and standard polystyrene latex samples in dispersion respectively. T...

We use a mesoscopic computer simulation method to study the interplay between hydrodynamic and Brownian fluctuations during steady-state sedimentation of hard sphere particles for Peclet numbers (Pe) ranging from 0.1-15. Even when the hydrodynamic interactions are an order of magnitude weaker than Brownian forces, they still induce backflow effects that dominate the reduction of the average sed...

A unified framework for particulate two-phase flow is presented with a wide range of solid particle concentration from dilute to dense limit. The simulated by two coupled solvers, that is, the gas-kinetic scheme (GKS) gas phase and wave–particle method (UGKWP) phase. GKS second-order Navier–Stokes solver. UGKWP multiscale all regimes. wave decomposition in depends on cell's Knudsen number (Kn)....

A particle-dynamics simulation is a tool for investigating nonequilibrium phenomena accompanied with hydrodynamic, thermodynamic motions, and even with phase transitions. In this article, several applications of the particledynamics simulation and a new computational method of particle dynamics are reported.

Abstract. In this paper, the global existence of smooth solutions for the three-dimensional (3D) non-isentropic bipolar hydrodynamic model is showed when the initial data are close to a constant state. This system takes the form of non-isentropic Euler–Poisson with electric field and frictional damping added to the momentum equations. Moreover, the L-decay rate of the solutions is also obtained...

The smooth quantum hydrodynamic model is an extension of the classical hydrodynamic model for semiconductor devices which can handle in a mathematically rigorous way the discontinuities in the classical potential energy which occur at heterojunction barriers in quantum semiconductor devices. Smooth QHD model simulations of the current-voltage curves of resonant tunneling diodes are presented wh...

We review the state-of-the-art in the modelling of the aggregation and collective behavior of interacting agents of similar size and body type, typically called swarming. Starting with individual-based models based on “particle”-like assumptions, we connect to hydrodynamic/macroscopic descriptions of collective motion via kinetic theory. We emphasize the role of the kinetic viewpoint in the mod...

We address the collective dynamics of non-Brownian particles cruising in a confined microfluidic geometry and provide a comprehensive characterization of their spatiotemporal density fluctuations. We show that density excitations freely propagate at all scales, and in all directions even though the particles are neither affected by potential forces nor by inertia. We introduce a kinetic theory ...