Qingen Meng

• PhD, MSC, BSC
• Lecturer in Mechanical Engineering at University of Leeds

The present study investigated the influence of various gait patterns on the viscoelastic squeeze-film lubrication characteristics of UHMWPE-based artificial hip replacements. Different gait loads (slow walking, normal walking, slow running) measured by Bergmann et al. were adopted in the present lubrication simulation. A comprehensive squeeze-film...

An optical interference test rig with spinning elastohydrodynamic lubrication (EHL) was established to investigate the spinning lubrication performance under different oil-supply conditions. Variations in the shape and thickness of the film versus the velocity, the load, and the spinning factor under fully flooded lubrication were discussed, and th...

This paper reviews the recent advancements in computational modelling of the lubrication of hip and knee joint replacements, especially those concerning Professor Duncan Dowson’s contribution. The review starts with the development of modelling the five key parameters that appeared in the pioneered Hamrock–Dowson formula. Then, the theory and appro...

Background and objective Investigating the biomechanics of cartilage could help to understand the unique load-bearing property of the cartilage and optimize the scaffold design in tissue-engineering. It is important to model the cartilage as a highly inhomogeneous fibril-reinforced biphasic material to represent its complex composition and structur...

Abstract Many studies have been performed to analyse the lubrication of artificial joints since the pioneer work by the late Professor Duncan Dowson. However, the viscoelastic deformation of one of the most widely used bearing materials, ultra‐high‐molecular‐weight polyethylene (UHMWPE), has only been considered recently. The described study attemp...

A two-scale homogenization method for modelling the hydrodynamic lubrication of mechanical seals with isotropic roughness was developed and presents the influence of surface topography coupled into the lubricating domain. A linearization approach was derived to link the effects of surface topography across disparate scales. Solutions were calculate...

This study attempted to provide insights into validating computational lubrication modelling of hip replacements. Direct comparisons between experimental measurements and numerical simulations were conducted for the central film thickness in a CoCr-on-glass hip bearing pair. A low-viscosity mineral oil and a 25% bovine serum were used as lubricants...

The viscoelasticity of the UHMWPE liner may play an important role in the lubrication performance of soft artificial hip joints. All the previous lubrication analyses for UHMWPE hip implants assumed that the UHMWPE liner was linear elastic. In order to investigate the influence of viscoelasticity of the UHMWPE liner, a transient viscoelastic lubric...

The geometry of the articular components of the knee is an important factor in predicting joint mechanics in computational models. There are a number of uncertainties in the definition of the geometry of cartilage and meniscus, and evaluating the effects of these uncertainties is fundamental to understanding the level of reliability of the models....

The highly inhomogeneous distribution of collagen fibrils may have important effects on the biphasic mechanics of articular cartilage. However, the effect of the inhomogeneity of collagen fibrils has mainly been investigated using simplified three-layered models, which may have underestimated the effect of collagen fibrils by neglecting their reali...

Background Globally, 1% of the population is affected by arthritis of the foot and ankle. Post-traumatic osteoarthritis, resulting from ankle injury or chronic ankle instability, accounts for more than 50% of these cases. Total ankle replacement (TAR) was developed as an alternative to fusion to treat end-stage arthritis whilst preserving some natu...

Lubrication plays an important role in the clinical performance of the ceramic-on-ceramic (CoC) hip implant in terms of reducing wear and avoiding squeaking. All the previous lubrication analyses of CoC hip implants assumed that synovial fluid was sufficiently supplied to the contact area. The aim of this study was to investigate the lubrication pe...

We systematically elucidate the effects of radial clearance on the wear behavior of hip joint prostheses bearings during run-in-stage. The results indicated that bearings with smaller radial clearances exhibited lower wear rate and less abrasive wear characterized by mild surface roughness and sphericity. The contact mechanics and lubrication regim...

The knee joint is one of the most common sites for osteoarthritis, the onset and progression of which are believed to relate to the mechanical environment of cartilage. To understand this environment, it is necessary to take into account the complex biphasic contact interactions of the cartilage and menisci. In this study, the time-dependent contac...

To investigate the combined effects of wear and corrosion on the performance of metal-on-metal total hip replacements, tribocorrosion tests were performed on 36 mm diameter joint replacements in an instrumented hip simulator. Corrosion related damage contributed significantly to material loss and to the formation of metal ions, and varied throughou...

Ceramic-on-metal (CoM) total hip replacements have shown reduced wear and friction. Lubrication and contact mechanics analyses play an important role in providing an overall understanding for the tribological performance of CoM bearings. In the present study, the steady-state contact mechanics and elastohydrodynamic lubrication (EHL) and transient...

Articular cartilage plays an important role in the function of diarthrodial joints. Computational methods have been used to study the biphasic mechanics of cartilage, and Abaqus has been one of the most widely used commercial software packages for this purpose. A newly developed open-source finite element solver, FEBio, has been developed specifica...

It is important to study the lubrication mechanism of metal-on-metal hip resurfacing prosthesis in order to understand its overall tribological performance, thereby minimize the wear particles. Previous elastohydrodynamic lubrication studies of metal-on-metal hip resurfacing prosthesis neglected the effects of the orientations of the cup and head....

DefinitionLubrication modeling of artificial hip joints generally refers to the investigation of the lubrication regime and associated lubrication characteristics such as film thickness and pressure of artificial hip joints using theoretical and computational methods. Wear of artificial hip joints is an important issue that limits the application o...

Effective lubrication performance of metal-on-metal hip implants only requires optimum conformity within the main loaded area, while it is advantageous to increase the clearance in the equatorial region. Such a varying clearance can be achieved by using non-spherical bearing surfaces for either acetabular or femoral components. An elastohydrodynami...

As an alternative material combination, metal-on-metal (MOM) hip replacement has attracted a revived interest due to its very low wear rates. In this article, an elastohydrodynamic lubrication analysis is performed for an MOM hip replacement with specific geometrical designs: a macro Alpharabola geometry of the cup bearing surface and micro-dimples...

Various complex structures are employed in different metal-on-metal (MOM) hip prostheses for different purposes. For the elastohydrodynamic lubrication (EHL) study of these prostheses, the elastic deformation calculation is not a trivial task due to the effect of complex structures. The finite-element method (FEM) is an attractive approach for solv...

On the elastohydrodynamic lubrication analysis, one of the most time-consuming issues is the calculation of surface deformation. Two methods are usually adopted to fasten the calculation: the multi-level multi-integration (MLMI) and the fast Fourier transform (FFT). However, in spherical models such as for hip joint replacements, the finite-element...

Diameter and diametral clearance of the bearing surfaces of metal-on-metal hip implants and structural supports have been recognised as key factors to reduce the dry contact and hydrodynamic pressures and improve lubrication performance. On the other hand, application of aspherical bearing surfaces can also significantly affect the contact mechanic...

The effect of a novel aspherical bearing surface, Alpharabola, which is defined as equation (1), on lubrication of MOM hip implants was investigated. The Reynolds equation was solved by the multi-grid (MG) method and the elastic deformation equation was solved by multi-level multi-integration (MLMI) method with the elastic deformation influence coe...

Elastohydrodynamic lubrication (EHL) of a metal-on-metal hip implant was investi-gated under quasi-static operating conditions. Various numerical methods, such as Newton – Raphson (N –R), multi-grid (MG), multi-level multi-integration, and fast Fourier transform technique (FFT), were considered and compared in terms of the convergence and accuracy...

The isothermal elliptical contact pure-spinning elastohydrodynamic lubrication (EHL) problem was studied. Complete numerical solution to the problem was obtained for various parameters with a multi-grid solver. The influence of the spinning velocity, the load, the elliptical ratio and the computation domain on the film thickness and pressure was in...

On the elasto-hydrodynamic lubrication (EHL) analysis one of the most important and time-costing issues is the calculation of surface elastic deformation, especially when a large number of grid nodes are involved. In order to achieve satisfied numerical accuracy within acceptable computation time, two methods are usually adopted to fasten the calcu...