Efficient turbulent entrainment causes otherwise dense volcanic jets to rise high into the atmosphere as buoyant plumes. Classical models suggest that the inflow of air is 10–15% of the axial velocity, giving predictions for the height of the plume and, in turn, the composition and structure of the resulting umbrella clouds. Crucially, entrainment is assumed independent of source geometry and m...

A Monte Carlo technique is described for simulating the high-speed flow of a rarefied gas around a cylindrical body. The method uses a hard-sphere model, or, alternatively, the "Maxwellian" model to compute collisions between particles. A representative "test particle" is scattered in such a way that its statistical behavior approximates that of a random particle chosen from the actual gas. Thi...

Trapped particle modes and the associated asymmetry-induced transport are characterized experimentally in cylindrical electron plasmas. Axial variations in the electric or magnetic confinement fields cause the particle trapping, and enable the E3B drift trapped-particle modes. Collisional diffusion across the trapping separatrix causes the modes to damp, and causes bulk radial transport when th...

A short, intense particle beam can drive a very large amplitude plasma wave or wakefield. The longitudinal component of the wakefield results in energy loss of the bulk of the beam and gain of the particles in the beam tail. First, a systematic investigation of the longitudinal fields excited in a plasma by a short, dense beam of electrons or positrons is carried out using two-dimensional, cyli...

In granular flow operations, often particles are nonspherical. This has inspired a vast amount of research in understanding the behavior of these particles. Various models are being developed to study the hydrodynamics involving nonspherical particles. Experiments however are often limited to obtain data on the translational motion only. This paper focusses on the unique capability of Magnetic ...

Capture of suspended particles by cylindrical collectors is an important mechanism in many aquatic processes, such as larval settlement, suspension feeding, and vegetative filtration. The collector Reynolds number (Rec), based on the collector diameter, typically ranges from 1-1000 in aquatic environments. No analytical solutions exist to describe capture efficiency in this range. Laboratory ex...

During the pneumatic conveying of plastic pellets, it has been observed that materials with similar physical characteristics may develop a substantial difference in pressure drop. In this work, the pressure drop in a particle-laden 2.7 meter long horizontal channel with circular cross-section is presented from an experimental perspective. Experiments are carried out for cylindrical polystyrene ...