We consider the dynamics of a hollow cylindrical shell that is filled with viscous fluid and another, nested solid cylinder, and allowed to roll down an inclined plane. A mathematical model is compared to simple experiments. Two types of behaviour are observed experimentally: on steeper slopes, the device accelerates; on shallower inclines, the cylinders rock and roll unsteadily downhill, with ...

This paper presents a new deployable reflector concept for an Earth observation mission that requires a low-cost L-band Synthetic Aperture Radar (SAR) instrument with a large aperture. A novel “hollow solid” structural concept is proposed that comprises curved surfaces formed from thin sheets of carbon-fiber-reinforced-plastic connected by flexible hinges along the edges. The front surface of t...

Calcareous sediments are located in temperate and tropical areas near offshore hydrocarbon industries and petrochemical reserves such as the Persian Gulf of Iran. These sediments have complicated physical properties which make them completely different from silicate soils. Carbonate sediments are mainly formed by the skeletal remains of marine organisms. Therefore, a wide variety of engineering...

Quenching cooling rate of rotary hollow cylinder by one row of water impinging jets has been experimentally studied. Water jets (d = 8 mm) with sub-cooling 55 to 85 ◦C and Reynolds number 8,006 to 36,738 impinged over rotary hot hollow cylinder (rotation speed 10 to 70 rpm) with initial temperature 250 to 600 ◦C. Impingement impact angle of row of jets varied between 0 to 135 ◦ and jet-to-jet s...

A cooling system, consisting of a chimney and a radial heat sink, was developed for a light-emitting diode (LED) downlight to replace a conventional light for saving energy. Natural convection was simulated with a numerical model that was verified experimentally. When the chimney was installed around the radial heat sink, the cooling efficiency of the heat sink was improved because the cooling ...

A modular particle-continuum (MPC) numerical method is used to simulate steady-state hypersonic flows which exhibit local regions of non-equilibrium embedded within mainly continuum flow fields. The MPC method loosely couples direct simulation Monte Carlo (DSMC) and Navier-Stokes (NS) methods which operate in different regions, use different mesh densities, and are updated using different sized...

Recent studies have shown that there is a direct link between the orientation of the nerve fibers in white matter (WM) and the contrast observed in magnitude and phase images acquired using gradient echo MRI. Understanding the origin of this link is of great interest because it could offer access to a new diagnostic tool for investigating tissue microstructure. Since it has been suggested that ...

In this study, the mechanical behaviours of thick-walled hollow functionally graded material (FGM) cylinder subjected to uniform pressures at inner and outer surfaces are proposed. The FGM has variable geometric profile, thickness properties like elastic modulus mass density all assumed vary radially according exponentially-varying functions in radial direction. With help infinitesimal elastici...

This study examines the use of the recently developed hollow core kagome lattice fibers for delivery of high power laser pulses. Compared to other photonic crystal fibers (PCFs), the hollow core kagome fibers have larger core diameter (~50 µm), which allows for higher energy coupling in the fiber while also maintaining high beam quality at the output (M² = 1.25). We have conducted a study of th...

A hollow cylinder apparatus was used to study some engineering properties of hollow cylindrical sand specimens prepared using the wet-pluviation technique. The refined specimen preparation method displayed good repeatability. Wet pluviation produced inherently cross-anisotropic specimens, with the level of initial anisotropy reducing with decreasing initial void ratio. The variation in the init...