Abstract: To overcome the weakness of conventional models in describing compressing flow especially in start and end stages the shear rate derivative was added to the right side of PTT constitutive equation. The ability of describing the well-known ‘shear shinning’ and ‘stretch harden’ phenomena was first illustrated by theoretical analysis. Then the governing equations for compressing flow were established in terms of incompressible and isothermal fluid,... More

Abstract: The principal rule for the stuffing-box packings is to ensure the stem valve sealing. The behavior of these systems is affected by the operating conditions, which are the gland axial stress, the temperature, and the fluid pressure, as well as the mechanical and geometrical properties of the various components. In this paper, a numerical study using finite element method is presented to evaluate the radial contact stresses, the axial stresses,... More

Abstract: Fretting fatigue has been studied mainly under constant normal loading, as it requires simple equipment which can be assembled on a universal fatigue testing machine. Recently, we [1] have introduced an innovative fretting fatigue apparatus in which the contact pressure can independently be varied during the test. In a recent publication [2] we have investigated the effect of normal load frequency on fretting fatigue life of Al7075-T6 under... More

Abstract: The short communication is devoted to validate the reliability and convergence of Optimal Homotopy Analysis Method (O-HAM). Owing the importance of present validation of O-HAM one can implement this method towards nanofluid flow narrating differential equations at larger scale for better description. To be more specific, the fractional order differential equation due to vertically moving non-spherical nano particle in a purely viscous liquid and... More

Abstract: Friction Stir Welding (FSW) technology is increasingly used in aerospace, automotive, construction and other industries. It allows for safe, secure and long-lasting joining of materials that are difficult to weld or non-weldable with traditional methods. In engineering practice, these are primarily aluminium alloys. This article discusses the basic issues related to the FSW technology. The macrostructure of a typical weld is presented. The... More