In this project, nonlinear characteristics on the rolling interface of a linear guide were studied by the finite element analysis and experimental verification. Contact of the ball/surface rolling interface in the rolling guides was simulated as a three-dimensional membrane element without thickness. By introducing Hertzian contact theory and applying proper normal/shear stiffness to such conta...

Background. This study aimed to assess contact between Recon Shell reinforcement cages used in revision hip arthroplasty and the bony base. Radiographic examinations were performed with the use of multi-energy computed tomography. Material and methods. We tentatively assess the fixation of Burch-Schneider reinforcement cages (Recon Shell made by Aesculap company) implanted in 10 patients, using...

Insect adhesion is mediated by thin fluid films secreted into the contact zone. As the amount of fluid affects adhesive forces, a control of secretion appears probable. Here, we quantify for the first time the rate of fluid secretion in adhesive pads of cockroaches and stick insects. The volume of footprints deposited during consecutive press-downs decreased exponentially and approached a non-z...

A lubricated contact suffers from starvation when the lubricant does not fill the contact inlet adequately. Such a situation arises due to short lubricant supply or at extremely high speeds. The starvation effect is modeled by shifting the position of the inlet meniscus towards the contact zone. The degree of starvation, so obtained, is plotted as a function of the position of inlet meniscus un...

-Properties of elastic solutions to interface crack problems are discussed in both the open formulation, in which the crack faces are assumed to be traction-free and interpenetration is permitted, and the unilateral formulation, where a contact zone is generally established adjacent to the crack tips. It is shown that if the contact zone is sufficiently small compared with the other dimensions ...

The eastern oyster (Crassostrea virginica Gmelin) is an economically and ecologically valuable marine bivalve occurring in the Gulf of Mexico. This study builds upon previous research that identified two divergent populations of eastern oysters in the western Gulf of Mexico. Allelic and genotypic patterns from 11 microsatellite markers were used to assess genetic structure and migration between...

A general approach to numerically simulating wear in rolling and sliding contacts is presented in this thesis. A simulation scheme is developed that calculates the wear at a detailed level. The removal of material follows Archard‟s wear law, which states that the reduction of volume is linearly proportional to the sliding distance, the normal load and the wear coefficient Careful attention is p...

The present work deals with the numerical solution of dynamic contact and fracture problems. The contact problem is a Signorini problem with or without Coulomb friction. The fracture problem uses a cohesive zone model with a prescribed crack path. These problems are characterized by a non-regular boundary condition and can be formulated with evolutionary variational inequations or di erential i...

The paper describes an advanced discrete-element based mechanical model, which allows modelling contact interaction of ductile materials with taking into account fracture and surface adhesion by the cold welding mechanism. model these competitive processes from a unified standpoint uses plastic work deformation as criterion both local chemical bonding surfaces in spots. Using this we carried ou...

The numerical simulation of the crack welding process is reported in this paper. The thermo-electro-structural coupled-field finite element analysis is adopted to investigate the welding process of crack surfaces. In the simulation, the pressure-dependent and temperature-dependent electrical contact conditions are considered. From the results, the crack surfaces can melt and weld together under...