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In the application of hydrostatic double-layered porous journal bearings, instability of bearing systems is a major problem. On the other hand, the use of non-Newtonian fluid as a lubricant is more practical in the present days. Furthermore, in case of porous bearing, neglecting slip effect and percolation effect of additives into the pores may lead to erroneous result. Hence, this paper aims to present the linear stability analysis of finite hydrostatic double-layered porous journal bearings lubricated with coupled-stress lubricant with tangential velocity slip and percolation effect.

First, considering the tangential velocity slip, the most general modified Reynolds-type equation has been derived for the film region and the governing equations for flow in the coarse and fine layers of porous medium incorporating the percolation effect. A linearized first-order perturbation method has been applied to obtain the threshold of stability in terms of critical mass parameter. The effect of various parameters on the stability is investigated and represented in the form of graphs. Furthermore, a comparison between the stability of double- and single-layered porous journal bearings has been exhibited.

In this paper, threshold of stability has been obtained in terms of critical mass parameter. The effect of slip coefficient, percolation factor, coupled-stress parameter, eccentricity ratio and bearing feeding parameter on the stability has been found.

There is no literature available so far that addresses the analysis of the linear stability of externally pressurized double-layered porous journal bearings with slip flow, including the percolation effect under coupled-stress lubrication. But in this paper, all these points are included which made this paper valuable in design purpose.

In the application of hydrostatic double-layered porous journal bearings, misalignment of bearing systems is a major problem. On the other hand, the use of coupled-stress fluid as a lubricant is more practical in the present days. Furthermore, in case of porous bearing, neglecting slip effect and percolation effect of additives into the pores may lead to erroneous result. Hence, this paper aims to address the effect of journal misalignment and coupled-stress lubricant on the steady-state film pressure of the double-layered porous journal bearing with tangential velocity slip and percolation effect.

First, considering the tangential velocity slip, the most general modified Reynolds type equation has been derived for the film region and the governing equations for flow in the coarse and fine layers of porous medium, incorporating the percolation effect for a double-layered porous bearing. Here, considering the misalignment caused by shaft displacement. Film thickness expression established considering the effect of misalignment. Steady-state film pressures are obtained by solving modified Reynolds equation based on the coupled-stress lubrication theory. Effects of journal misalignment and coupled-stress lubricant on the pressure profiles in the film region are discussed and demonstrated in the graphical form.

In this paper, effects of journal misalignment and coupled-stress lubricant on the pressure profiles in the film region are obtained. In general, higher degree of misalignment gives higher steady-state pressure value in the film region, and this pressure increases due to increase in coupled-stress parameter up to a certain limit.

To the best of the author’s knowledge, there is no literature available, so far, that addresses the analysis of the steady-state pressure in the film region of a doubled–layered porous journal bearing under misaligned condition with coupled-stress lubricant. But in this paper all these points are included, which makes this article valuable in design purpose.

The purpose of this paper is to put forward the lubrication model of oil bearing and enrich the design theory under the condition of mixed lubrication.

A mixed lubrication model of bilayer porous bearing is established. The effects of the working conditions on the lubrication performance and seepage behavior were analyzed.

Results show that the oil film pressure mainly occurs in the bearing convergence zone and contact pressure mainly occurs near the minimum film thickness. The oil infiltrates into the porous matrix in the contact area and precipitates out to the friction surface at the inlet of the contact area. The oil seepage velocity and dynamic pressure effect at the friction interface can be improved by reasonably matching the load and speed. With the decrease of the external load or increase of the rotating speed, the lubrication performance becomes well.

This study provides a reference for the design and application of oil bearing under harsh working conditions.

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.

The present paper aims to analyse the synergistic effect of pocket orientation and piezo-viscous-polar (PVP) lubrication on the performance of multi-recessed hybrid journal bearing (MHJB) system.

To simulate the behaviour of PVP lubricant in clearance space of the MHJB system, the modified form of Reynolds equation is numerically solved by using finite element method. Galerkin’s method is used to obtain the weak form of the governing equation. The system equation is solved by Gauss–Seidal iterative method to compute the unknown values of nodal oil film pressure. Subsequently, performance characteristics of bearing system are computed.

The simulated results reveal that the location of pressurised lubricant inlets significantly affects the oil film pressure distribution and may cause a significant effect on the characteristics of bearing system. Further, the use of PVP lubricant may significantly enhances the performance of the bearing system, namely.

The present work examines the influence of pocket orientation with respect to loading direction on the characteristics of PVP fluid lubricated MHJB system and provides vital information regarding the design of journal bearing system.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2023-0241/

This paper aims to advance the squeeze film characteristics of long partial journal bearings with couple stress fluid studied by Lin to include the effect of permeability on the squeeze film lubrication of long partial porous journal bearings with couple stress fluids.

A semi‐analytical and semi‐numerical solution for the squeeze film lubrication of long porous partial journal bearings lubricated with couple stress fluid is presented in the paper. The modified Reynolds equation governing the fluid film pressure is derived. The modified Reynolds equation is solved analytically and closed form expressions for the squeeze film pressure and load carrying capacity are presented. The first‐order non‐linear equation for the time‐height relation is solved numerically with the given initial condition. The effect of couple stresses and permeability on the squeeze film characteristics are discussed.

It is found that the effect of couple stresses is to increase the load carrying capacity and to lengthen the squeeze film time as compared to the corresponding Newtonian case. The effect of permeability is to reduce the load carrying capacity and to decrease the squeeze film time as compared to the corresponding solid case.

In the design of porous partial journal bearings, the reduction in the load carrying capacity and the response time can be compensated by the use of lubricants with proper microstructures by which the bearing life can be increased.

To study the combined effects of permeability and couplestresses on the performance characteristics of a secant‐shaped porous slider bearing lubricated with Stokes couplestress fluid.

The modified Reynolds type equation governing the fluid film pressure is derived on the basis of Stokes microcontinuum theory of couplestress fluids by using Beavers‐Joshep slip boundary conditions at the fluid‐porous interface. The modified Reynolds equation is solved analytically and closed form expressions are obtained for the fluid film pressure, load carrying capacity, frictional force and centre of pressure.

The bearing characteristics are computed for various values of the couple stress parameter, slip parameter and the permeability parameters. It is found that, the effect of couple stress is to increase the load carrying capacity and to decrease the coefficient of friction as compared to the Newtonian case. However, the effect of permeability parameter is to decrease the load carrying capacity. It is also found that, the effect of couple stresses is to shift the center of pressure towards the outlet edge.

The end effects are neglected in the analysis and these can be included in the study by considering full three‐dimensional problem.

Reduction in the load carrying capacity due to the presence of porous facing can be compensated by the use of lubricants containing additives of proper size. As a result the bearing performance can be improved.

This paper provides closed form expressions for the bearing characteristics and are analyzed with respect to non‐dimensional parameters, viz. couplestress parameter, slip parameter and permeability parameter. This paper offers help to design engineers to design efficient bearing systems.

This bibliography is offered as a practical guide to published papers, conference proceedings papers and theses/dissertations on the finite element (FE) and boundary element (BE) applications in different fields of biomechanics between 1976 and 1991. The aim of this paper is to help the users of FE and BE techniques to get better value from a large collection of papers on the subjects. Categories in biomechanics included in this survey are: orthopaedic mechanics, dental mechanics, cardiovascular mechanics, soft tissue mechanics, biological flow, impact injury, and other fields of applications. More than 900 references are listed.

Sheet metal forming is a process of shaping thin sheets of metal by applying pressure through male or female dies or both. In most of used sheet‐formating processes the metal is subjected to primarily tensile or compressive stresses or both. During the last three decades considerable advances have been made in the applications of numerical techniques, especially the finite element methods, to analyze physical phenomena in the field of structural, solid and fluid mechanics as well as to simulate various processes in engineering. These methods are useful because one can use them to find out facts or study the processes in a way that no other tool can accomplish. Finite element methods applied to sheet metal forming are the subjects of this paper. The reason for writing this bibliography is to save time for readers looking for information dealing with sheet metal forming, not having an access to large databases or willingness to spend own time with uncertain information retrieval. This paper is organized into two parts. In the first one, each topic is handled and current trends in the application of finite element techniques are briefly mentioned. The second part, an Appendix, lists papers published in the open literature. More than 900 references to papers, conference proceedings and theses/dissertations dealing with subjects that were published in 1995‐2003 are listed.