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...

The heat pipe applications have been coupled with the renewable energy such as solar energy, waste heat and geothermal energy. Thermosyphon Rankine Cycle (TRC) is a vertical wickless heat pipe engine. In this engine, the turbine is installed between the insulated section and a condenser section of thermosyphon. The mechanical energy developed by the turbine can be converted to electricity, by d...

Granular pipe flows are characterized by intermittent behavior and large, potentially destructive solid fraction variations in the transport direction. By means of particle-based numerical simulations of gravity-driven flows in vertical pipes, we show that it is possible to obtain steady material transport by adding a helical texture to the inner-wall of the pipe. The helical texture leads to a...

A series of experiments was carried out using a dual sensor conductance probe to measure the local axial oil velocity distribution and the local oil volume fraction distribution in vertical, oil in water bubbly flows in an 80mm diameter vertical pipe. Values of the water superficial velocity were in the range 0.276 1 ms to 0.417 1 ms , values of the oil superficial velocity were in the range 0....

Steady-state and transient experiments of water–gas, oil–water and oil–water–gas multiphase flows were conducted on a transparent 11 m long, 15 cm diameter, inclinable pipe using kerosene, tap water and nitrogen. The pipe inclination was varied from 0 (vertical) to 92 and the flow rates of each phase were varied over wide ranges. Fast-acting valves enabled the trapping of the fluid flowing in t...

Gas volume fraction and velocity profiles: vertical and inclined bubbly air-water flows Original Citation Lucas, Gary (2006) Gas volume fraction and velocity profiles: vertical and inclined bubbly air-water flows. Users may access full items free of charge; copies of full text items generally can be reproduced, displayed or performed and given to third parties in any format or medium for person...

In recent years, the production of oil and gas has been developed in deep water depths which exceed 500m. Deep water developments are being followed strongly in different parts of the world (Caspian Sea, Gulf of Mexico, etc.). The movement of floater causes severe stress at the touchdown point (TDP) in steel catenary risers (SCR). The main objective of this study was to simulate the exact behav...