in this work, improved heat generation models are developed for straight and tapered shoulder geometries with different tool pin profiles in friction stir welding. the models are developed considering the welding process as a combination of the pure sliding and the pure sticking conditions. from the results, the amount of heat generation is directly proportional to the number of edges in the pi...

The gas flow through porous media including that of multiple species is frequently described by the binary friction model (BFM) considering the binary diffusion, Knudsen diffusion, and viscous flow. Therefore, a numerical simulation was performed on a microporous support of an asymmetric oxygen transport membrane. As its exact numerical solution is complicated and not always possible, the resul...

We did an experimental study on Taylor-Couette flow in between two coaxial cylinders of length L = 220 mm and radii r i = 110 and r o = 120, respectively, the fluid-filled 'Taylor-Couette gap' or TC-gap being h = 10 mm, thus gap ratio η = r i /r o = 0.917, and gap aspect ratio L/h = 22). Both cylinders are rotating independently, with angular frequencies ω i,o , The torque T on the inner cylind...

Thermodynamic analysis of a steady state flow and heat transfer of an Oldroyd 8-constant fluid with effect of heat source, velocity slip and buoyancy force under tranverse a magnetic field is is carried out in this paper. The model for momentum and energy balance is tackled numerically using Method of Weighted Residual (MWR). Partition method is used to minimize the associated residuals. The re...

We consider a body immersed in a perfect gas and moving under the action of a constant force. Body and gas are in thermal equilibrium. We assume a stochastic interaction body/medium: when a particle of the medium hits the body, it is absorbed and immediately re-emitted with a Maxwellian distribution. This system gives rise to a microscopic model of friction. We study the approach of the body ve...

In the present work, thermo-fluidic behavior of a heat exchanger tube with conical shaped insert has been investigated help finite volume method. To enhance transfer rate, two different types roughness used in i.e. protrusion and dimple roughness. A three-dimensional computational model RNG turbulence is for simulation it performed three diameters (3 mm, 6 mm 9 mm) pitch space (120 180 both The...

This paper reports on spatially resolved measurements of the shear stress distribution at a frictional interface between a flat rubber substrate and a glass lens. Silicone rubber specimens marked close to their surface by a colored pattern have been prepared in order to measure the surface displacement field induced by the steady-state friction of the spherical probe. The deconvolution of this ...

Abstract—The presence of bubbles in the boundary layer introduces corrections into the log law, which must be taken into account. In this work, a logarithmic wall law was presented for bubbly two phase flows. The wall law presented in this work was based on the postulation of additional turbulent viscosity associated with bubble wakes in the boundary layer. The presented wall law contained empi...