We describe a Lagrangian particle advection scheme which is intended for use in hybrid finite-volume (FV) large-eddy simulation/filtered density function (LES/FDF) methods for low-Mach flows, but which may also be applicable to unsteady probability density function (PDF) methods, direct numerical simulation (DNS) or any other situation where tracking fluid particles is of concern. A key ingredi...

Holographic particle image velocimetry (HPIV) is presently the only method that can measure at high resolution all three components of the velocity in a finite volume. In systems that are based on recording one hologram, velocity components parallel to the hologram can be measured throughout the sample volume, but elongation of the particle traces in the depth direction severely limits the accu...

The occurrence of heterogeneous flow structures in gas-particle flows seriously affects the gas-solid contacting and transport processes in high-velocity gas-fluidized beds. Particles do not disperse uniformly in the flow but pass through the bed in a swarm of clusters. The so-called “core-annulus” structure in the radial direction and “S” shaped axial distribution of solids concentration chara...

The local solid flow structure of gas-solid bubbling fluidized bed was investigated to identify and characterize the particle clusters. Extensive mathematical calculations were carried out using the energy-minimization multi-scale (EMMS) approach for evaluating cluster properties including the velocity, the size and the void fraction of clusters in the dense phase of the bed. The results showed...

The paper presents a rigorous derivation of the velocity autocorrelation function for an anomalously diffusing slow solute particle in a bath of fast solvent molecules. The result is obtained within the framework of the generalized Langevin equation and uses only scaling arguments and identities which are based on asymptotic analysis. It agrees with the velocity autocorrelation function of an a...

We discuss single-particle and two-particle statistics in twodimensional turbulent convection in the Bolgiano–Oboukhov regime by means of high-resolution direct numerical simulations. Relative separation of two particles is found to be described well by a generalization of the Richardson diffusion model. Single-particle velocity structure functions are dominated by large-scale eddies and theref...

The velocity distribution of a fluidized dilute granular gas in the direction perpendicular to the gravitational field is investigated by means of molecular dynamics simulations. The results indicate that the velocity distribution can be exactly described neither by a Gaussian nor by a stretched exponential law. Moreover, it does not exhibit any kind of scaling. In fact, the actual shape of the...

A modified smoothed particle hydrodynamic (MSPH) computational technique was utilized to simulate molten particle motion and infiltration speed on multi-scale analysis levels. The radial velocity and velocity gradient of molten alumina, iron infiltration in the TiC product and solidification rate, were predicted during centrifugal self-propagating high-temperature synthesis (SHS) simulation, wh...

In this paper, a new particle swarm optimization method has been proposed. In the proposed approach a novel philosophy of modifying the velocity update equation of Standard Particle Swarm Optimization approach has been used. The modification has been done by vanishing the gbest term in the velocity update equation of SPSO. The performance of the proposed algorithm (Personal Best Position Partic...