Shoulder geometry of tool plays an important role in friction-stir welding because it controls thermal interactions and heat generation. This work is proposed and developed a coupled rigid-viscoplastic numerical modeling based on computational fluid dynamics and finite element calculations aiming to understand these interactions. Model solves mass conservation, momentum, and energy equations in...

In this paper, transient solution of two dimensional asymmetric thermal and mechanical stresses for a hollow cylinder made of piezoelectric material is developed. Transient temperature distribution, as function of radial and circumferential directions and time with general thermal boundary-conditions, is analytically obtained, using the method of separation of variables and<br...

This paper is an attempt to determine quasi-static thermal stresses in a thin elliptical plate which is subjected to transient temperature on the top face with zero temperature on the lower face and the homogeneous boundary condition of the third kind on the fixed elliptical curved surface. The solution to conductivity equation is elucidated by employing a classical method. The solution of stre...

The present article deals with the analysis of thermal-bending stresses in a heated thin annular sector plate with simply supported boundary condition under transient temperature distribution using Berger’s approximate methods. The sectional heat supply is on the top face of the plate whereas the bottom face is kept at zero temperature. In this study, the solution of heat conduction is obtained...

This paper addresses the combined effects of couple stresses, thermal radiation, viscous dissipation and slip condition on a free convective flow of a couple stress fluid induced by a vertical stretching sheet. The Cogley- Vincenti-Gilles equilibrium model is employed to include the effects of thermal radiation in the study. The governing boundary layer equations are transformed into a system o...

A mathematical treatment is given of the effect of thermal distortion on the thermal contact resistance between two semi-infinite solids of different materials. Good agreement is achieved with experimental observations of thermal rectification due to Clausing. It is shown that problems of this type sometimes have no steady state solution and it is suggested that this is attributable to the disc...

The objective of this study is to investigate the thermal efficiency and power production of typical models of endoreversible heat engines at the regime of minimum entropy generation rate. The study considers the Curzon-Ahlborn engine, the Novikov's engine, and the Carnot vapor cycle. The operational regimes at maximum thermal efficiency, maximum power output and minimum entropy production rate...

The prime aim of this study was to investigate the thermal conductivity of concrete using crushed recycled glass as a fine aggregate. Influencing factors on thermal conductivity of concrete are investigated using The Unitherm Model 6000 Guarded Hot Plate Thermal Conductivity Instrument. A total of 36 concrete mixes were produced with different water cement ratios (0.4 and 0.5). Recycled glass w...

The first- and second-order temporal interference between two independent thermal and laser light beams is discussed by employing the superposition principle in Feynman's path integral theory. It is concluded that the first-order temporal interference pattern can not be observed by superposing two independent thermal and laser light beams, while the second-order temporal interference pattern ca...

   In this research, Graphene was synthesized by chemical vapor deposition (CVD) method in atmosphere pressure (14.7 psi). Different functionalization method was used for oxidizing of graphene such as acid and alkaline treatments. The Functionalized graphene (FG) was characterized by FTIR and Raman spectroscopy. Nanofluid with water and different concentration (0.05, 0.15 and 0.25 wt %) of ...