Abstract: The standard decoupled method with Newton-generalized minimum residual procedure performs poorly or may break down when used to solve certain elastohydrodynamic lubrication problems. The authors Zargari et al., 2007 presented decoupled and coupled methods in which the limitations of the decoupled method for some set of physical parameters and slight variation in these values (physical...

Binary droplet collision plays an elementary role in dense spray combustion. The collision outcome influences the spray characteristics, for example, the distributions of droplet size and velocity, local mixing rate, etc., and thus the overall combustion performance. In this paper, the dynamics and mixing of colliding droplets are preformed computationally and theoretically. All possible collis...

The aim of the paper work is to investigate and predict the static performance of journal bearing in turbulent flow condition considering micropolar lubrication. The Reynolds equation has been modified considering turbulent micropolar lubrication and is solved for steady state operations. The Constantinescu’s turbulence model is adopted using the coefficients. The analysis has been done for a p...

In this introductory paper for the Theme Issue on green tribology, we discuss the concept of green tribology and its relation to other areas of tribology as well as other 'green' disciplines, namely, green engineering and green chemistry. We formulate the 12 principles of green tribology: the minimization of (i) friction and (ii) wear, (iii) the reduction or complete elimination of lubrication,...

A very low coefficient of friction in joints makes it difficult to define clearly the mechanism of cartilage lubrication. The present paper describes the two currently predominant and mutually complementary views aiming to elucidate this mechanism. The first mechanism, referred to as hydrostatic lubrication, involves interstitial fluid pressurization from the cartilage and its importance for th...

Friction and wear are detrimental to engineered systems. Ultrasonic lubrication is achieved when the interface between two sliding surfaces is vibrated at a frequency above the acoustic range (20 kHz). As a solid-state technology, ultrasonic lubrication can be used where conventional lubricants are unfeasible or undesirable. Further, ultrasonic lubrication allows for electrical modulation of th...

In this work, the characteristic properties of the lubrication approximation are studied and its weak ellipticity is established, in contradistinction to the commonly accepted parabolic character of the lubrication equations resulting from the underlying unidirectional flow assumption. The weak ellipticity property allows the lubrication analysis to capture flow topologies around stagnation poi...

This paper describes a laboratory method for treatment of used engine oil FENIX SUPERIOR SAE 15W-40 with intention to decrease of sulfur and selected metal content at acceptable level. FENIX SUPERIOR SAE 15W-40, produced by manufacturer Joint Stock Company FAM Krusevac, is used for lubrication of the most modern four-stroke diesel and gas engines of passenger and commercial vehicles, engine con...

The journal bearings subjected to heavy load and slow speed operates in mixed lubrication regime causing contact between the interacting surfaces and resulting in wear. The complexity of wear behavior and lack of unifying theory/model make wear control very challenging. In the present research work, a methodology is outlined for the minimization of the wear of journal bearing operating in mixed...

Despite continuous progress toward tissue engineering of functional articular cartilage, significant challenges still remain. Advances in morphogens, stem cells, and scaffolds have resulted in enhancement of the bulk mechanical properties of engineered constructs, but little attention has been paid to the surface mechanical properties. In the near future, engineered tissues will be able to with...