We study the possible magnetization of cosmic voids by void galaxies. Recently, observations revealed isolated starforming galaxies within the voids. Furthermore, a major fraction of a voids volume is expected to be filled with magnetic fields of a minimum strength of about 10 −15 G on Mpc scales. We estimate the transport of magnetic energy by cosmic rays (CR) from the void galaxies into the v...

This paper addresses the void fraction of polydisperse particles with a Weibull (or Rosin-Rammler) size distribution. It is demonstrated that the governing parameters of this distribution can be uniquely related to those of the lognormal distribution. Hence, an existing closed-form expression that predicts the void fraction of particles with a lognormal size distribution can be transformed into...

Intense turbulence develops in the two-phase flow region of hydraulic jump, with a broad range of turbulent length and time scales. Detailed air–water flow measurements using intrusive phase-detection probes enabled turbulence characterisation of the bubbly flow, although the phenomenon is not a truly random process because of the existence of low-frequency, pseudo-periodic fluctuating motion i...

A simple set of equations for bubbly flow through a vertical tube is rigorously derived by means of a scale analysis from the realistic equations posed by Pauchon. It is shown that under steady flow conditions the void fraction will relax from its value at the inlet towards an asymptotic value within only a short distance of the inlet. The relationship between the inlet void fraction and the im...

The pressure variations associated with a filling undulating pipeline containing an entrapped air pocket are investigated both experimentally and numerically. The influence of entrapped air on abnormal transient pressures is often ambiguous because the compressibility of the air pocket permits the liquid flow to accelerate but also partly cushions the system, with the balance of these tendencie...

This paper reports the results of an experimental study conducted to characterise the gas-liquid multiphase flows experienced within a vertical riser transporting a range of gas-liquid flow rates. The scale experiments were performed using an air/silicone oil mixture within a 6 m long riser. The superficial air velocities studied ranged from 0.047 to 2.836 m/ s, whilst maintaining a liquid supe...