علي عبد الامير حسين الصفار

Ball-in-socket metal on metal (MOM) contacts were analysed using the Abaqus Finite Element package to simulate dry contact between the acetabular cup and the femoral head. Different cup thicknesses of 4, 6, 8, and 10 mm were considered using a polyurethane foam block support system. Elastohydrodynamic lubrication (EHL) analyses were developed for the contacts using three different approaches to specify the contact. These were (i) A simple model based on the radii of relative curvature, (ii) An equivalent contact model developed so that its dry contact area and maximum pressure replicated the values obtained from the FE analysis, and (iii) A modified version of (ii) that also ensured equivalence of the gap shape outside the contact area. Published in vivo information for the hip joint contact forces over the walking cycle was used to specify the operating conditions for the EHL analysis

A maximum static deflection and natural frequency of aluminium cantilever stepped beam (two steps) were investigated experimentally and theoretically for different values of small and large diameters and for different lengths of larger diameter step. Eighty samples of aluminium beams were manufactured using turning machine. The range of the beam diameter was 12–20 mm and the length of beam was 45 cm. Classical Rayleigh method, modified Rayleigh method and finite element using ANSYS software method were adopted to calculate the maximum static deflection and the natural frequency. A good agreement was found for the static deflection at different positions of applied load between the experimental results and the theoretical results, ANSYS and modified Rayleigh method.