The non-Newtonian character of granular flow in a vertical pipe is analyzed. The time evolution of the flow velocity and the velocity fluctuations (or granular temperature) is derived. The steady state velocity has a power law dependence on the pipe width with an exponent between 3/4 and 3/2. The flow becomes faster the more efficient the collisional cooling is, provided the density remains low...

Lower-branch traveling waves and equilibria computed in pipe flow and other shear flows appear intermediate between turbulent and laminar motions. We take a step towards connecting these lower-branch solutions to transition by deriving a numerical method for finding certain special disturbances of the laminar flow in a short pipe. These special disturbances cause the disturbed velocity field to...

Pipe vibration is often excited in the deep ocean by ship motions, wave forces and vortex shedding. Elastic joints along the pipe are modeled in an attempt to move the resonance frequencies away from the pipe system. The numerical examples focus on the investigation of single and multiple elastic joints along a long pipe and their effect on three-dimensional (3-D) nonlinear coupled pipe respons...

gas-lift pumps are devices for lifting liquid phase incorporating the gas phase to be injected in the bottom of liquid column. they are widely used in various industrial applications such as oil extracting in petroleum industries. gas-liquid flow being the main part of the flow through these systems, flowing in vertical pipes of gas-lift pumps has different regimes namely bubbly, slug, churn an...

This paper reported an experimental research of steady-state heat transfer behaviour of a gas flowing through a fixed bed under the different operating conditions. Studies had been carried out in a fixed-bed packed methanol synthesis catalyst percolated by air at appropriate flow rate. Both radial and axial direction temperature distribution had been investigated under the different operating c...

11 The Orapa Diamond Mine (Republic of Botswana) exposes a bi-lobate kimberlite 12 pipe that erupted during the Late-Cretaceous epoch (∼93 Ma) through Archaean 13 basement and volcano-sedimentary rocks of the Karoo Supergroup. Geological map14 ping of the crater zone of the South Pipe has revealed a 15–25 m thick in-situ 15 kimberlite pyroclastic flow deposit. The pyroclastic deposit fills in t...

Pipe systems are often used to transfer moderate to medium water volumes between reservoirs or from well fields to consumers. Such systems consisting of an arbitrary number of reservoirs or other types of sources and sinks are considered here. The Lagrangean optimization principle is used for the determination of all pipe diameters giving minimum total cost of the system, when the individual di...

INTRODUCTION We aim to elucidate the effect of spatial resolution of three-dimensional cine phase contrast magnetic resonance (3D cine PC MR) imaging on the accuracy of the blood flow analysis, and examine the optimal setting for spatial resolution using flow phantoms. MATERIALS AND METHODS The flow phantom has five types of acrylic pipes that represent human blood vessels (inner diameters: 1...