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This project aims at determining both numerical and experimental to some thermal properties and its thermal expansion coefficient, thermal conductivity and mechanical properties of reinforcement of fiber glass woven with matrix of multi wall carbon nanotube MWCNT / epoxy composite. First, this powder is known to have a very good thermal properties. So, the nanopartical combined with resin has poor thermal properties. Secondly, the development a complete solution for the manufacturing of multi wall carbon nanotube /epoxy composites different volume fraction from 1% to 10% with increment of 2% to compare the result of finite element method by using ANSYS program with experimental results to determine the mechanical and thermal properties for nanocomposite materials. The finite element by using ANSYS is good agreement with experimental data for different volume fraction. The thermal conductivity of the nanocomposite materials increases with increasing in the volume fraction concentration thermal expansion coefficient reduces with increasing in the volume fraction concentrations. The increment nano particle concentration effect on the mechanical properties is accomplished the best results.

Journal bearings in typical applications are subjected to misalignment due to several causes, such as shaft deformation under load and errors related to the installation and manufacturing processes. Misalignment has well-known severe negative consequences on the performance of the bearings. This paper deals with the bearing chamfer to reduce these consequences of misalignment, and two forms of bearing edge modification are considered in the analysis. These forms are linear and curved chamfering of the bearing edges, where the height of the chamfer in the circumferential direction and the length of the modification in the longitudinal direction are considered as geometrical design parameters. The investigation includes a numerical solution of the hydrodynamic lubrication problem of finite length journal bearing, considering 3D misalignment cases using the finite difference method. This includes the assessment of the chamfer forms and their effects on the bearing performance in terms of the main bearing design parameters. Furthermore, the stability of the chamfered bearings is also investigated under impact load. Results showed that both chamfer forms are beneficial for a certain limit of the design parameters in reducing the maximum pressure and coefficient of friction and in elevating the film thickness levels, extending the range of misalignment in which the journal bearing can operate safely. In addition, the chamfered bearings in both forms showed more stability range in terms of the critical speed and shaft center trajectories under impact load. The bearings with the curved chamfer, where the slope is continuous at the start of modification, showed more uniform film thickness levels, and their shaft center trajectories were closer to the perfectly aligned bearing in the stable operating range of the system.