Laminar, two-dimensional flow of an incompressible thixotropic fluid obeying Moore's model is investigated numerically in a slipper-pad bearing using FVM method. Results will be presented addressing the effect of thixotropic properties and inclination angle on the pressure distribution and load-carrying capacity of the bearing. It is shown that the pressure distribution under the upper pad depends only on the buildup-to-breakdown ratio. It is also predicted that by increasing this ratio, the load-carrying capacity increases, but, the pressure distribution becomes more and more asymmetric with the maximum pressure shifting towards the outlet section of the bearing. Also, for any given set of Moore's model parameters, an increase in the inclination angle is shown to linearly increase the load-carrying capacity of the bearing at small angles. Above a critical inclination angle, however, the rise in the load-carrying capacity becomes nonlinear. Also, by increasing the inclination angle, the location for the occurrence of maximum pressure shifts towards the outlet section of the bearing.

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In this research, the effects of aging temperature on the phase transformation, mechanical properties, and superelasticity of Ti-51.5 at.% Ni alloy were investigated. For this purpose, samples were solution annealed and then aged at different temperatures ranging from 300 to 700ºC. The results showed that the change of aging temperature has a great influence on the behavior of the alloy. Aging at 300 and 400ºC led to the occurrence of the austenite to R phase (A↔R) transformation. By aging at these temperatures, the ultimate tensile strength and elongation did not change significantly compared to the solution annealed sample. Aging at 500 and 600ºC lead to the appearance of B19´ phase during cooling cycle of differential scanning calorimetry tests. Samples aged at 500ºC and 600ºC showed the best mechanical properties, in comparison to the other aging temperatures. Maximum tensile strength of 1250 MPa and the elongation of 25% were obtained by aging at 500 and 600ºC, respectively. Solution annealed sample showed no superelastic property. Complete superelasticity was observed by aging at 400 and 500ºC.The sample aged at 700ºC showed the transformation behavior and mechanical properties similar to the solution annealed sample.

In the present work, laminar flow of an incompressible thixotropic fluid is investigated numerically above a fixed semi-infinite plate. Assuming that the fluid of interest obeys Harris' thixotropic rheological model, vorticity/stream function formulation will be used to reduce equations of motion. The equations so obtained are then solved numerically using the finite difference technique. It is shown that for the Harris model to represent true thixotropic fluids (in a Lagrangian sense) the thixotropic parameter appearing in this fluid model should be negative. Numerical results obtained at a typical location (say, in the middle of the plate) show that for the viscosity to decrease by an increase in the thixotropic parameter of Harris model, this fluid property should be negative. Interestingly, an increase in the velocity gradient near the wall combined with a decrease in the viscosity of the fluid is predicted to give rise to an increase in the wall shear stress regardless of the fluid being thixotropic.