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...

We analyze the steady non-Newtonian fluid–structure interaction between flow of an Oldroyd-B fluid and a deformable channel. Specifically, we provide theoretical framework for calculating leading-order effect fluid’s viscoelasticity on rate–pressure drop relation deformation channel’s elastic wall. first identify characteristic scales dimensionless parameters governing in slender shallow channe...

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...

We experimentally study the occurrence of pattern formation during slot-die coating partially wetting liquids onto polyethylenterephthalat-substrates outside window. The experimental investigation is supported by numerical simulations a dynamical model. Our results demonstrate that beyond critical speed, deposition homogeneous layers undergoes an instability resulting in self-organized emergenc...

In this report a concise review is given of the literature on slip phenomena at the wall of extrusion devices and the role of slip-laws in modeling of extrusion instabilities. In section 2 the main three instabilities are discussed: spurt, in which big pressure oscillations occur and the extrudate leaves the die in an oscillating way, sharkskin, which leads to more or less regular surface defec...

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...

die direktreduktion von eisenerzen zu eisenschwamm mittels erdgas wird iiberall dort verwendet wo einmal die notwendtigen rohstoffe und besonders der metallurgische koks zu wirtschaftlischen bedingungen fehlen. andereseirs wiederum miissen erdgasrerven in geniigenden mengen und qualitat zu verfugung stehen, urn die direktredution mit gutem wirkungsgrad durchfuhren zu konnen. in dieser arbeit wi...