Lubrication expressions for the friction coefficients of a spherical particle moving in a fluid between and along two parallel solid walls are explicitly evaluated in the low-Reynolds-number regime. They are used to determine lubrication expression for the particle free motion under an ambient Poiseuille flow. The range of validity and the accuracy of the lubrication approximation are determine...

In order to develop more efficient engines, it is essential to optimize the lubrication circuit of the power train systems. In this paper, during an engine design and development process, a network analysis of the engine lubrication system is described in detail. Two elements have been added to the lubrication circuit in the modified engine. These elements are hydraulic lifters and an Anti-drai...

The transition from boundary lubrication to fully hydrodynamic lubrication is investigated for air-lubricated slider bearings using the electrical resistance method. Intermittent contacts are shown to exist even under conditions for which the numerical solution of the Reynolds equation or white light interferometry predicts steady state spacings in the spacing region from 0.125 to 0.25 pm. The ...

In situ lateral force microscopy (LFM) and X-ray photoelectron spectroscopy (XPS) were used to probe the lubrication behavior of an aqueous solution of poly(oxyethylene)-poly(oxypropylene)-poly(oxyethylene) (PEO-PPO-PEO) symmetric triblock copolymer on thin films of polypropylene (PP), polyethylene (PE), and cellulose. LFM experiments were carried out while the substrates were immersed in water...

Articular cartilage is a highly efficacious water-based tribological system that is optimized to provide low friction and wear protection at both low and high loads (pressures) and sliding velocities that must last over a lifetime. Although many different lubrication mechanisms have been proposed, it is becoming increasingly apparent that the tribological performance of cartilage cannot be attr...

On 9 October 2001 two US oil companies Chevron and Texaco merged. Their long-term joint venture operation, known as Caltex (formed in 1936 and operating in East and Southern Africa, Middle East, Asia and Australasia), was incorporated into the one global energy company. This global enterprise will be highly competitive across all energy sectors, as the new company brings together a wealth of ta...

The tribological performance of an artificial hip joint has a particularly strong influence on its success. The principle causes for failure are adverse short- and long-term reactions to wear debris and high frictional torque in the case of poor lubrication that may cause loosening of the implant. Therefore, using experimental and theoretical approaches models have been developed to evaluate lu...