effects of some thermo-physical parameters on free convective heat and mass transfer over a vertical stretching surface at lowest level of heat energy in the presence of suction is investigated. the viscosity of the fluid is assumed to vary as a linear function of temperature and thermal conductivity is assumed constant. a similarity transformation is applied to reduce the governing equations i...

The effect of a height-dependent asperity radius of curvature is accounted for in a recently developed scaledependent model of contact and friction. The contact and friction model includes the effects of adhesion, using the Maugis model, and of scale-dependent friction, using the Hurtado and Kim single asperity friction model. This multiasperity model has been modified to include the effect of ...

This paper presents experimental measurements of the approach and rebound of a particle colliding obliquely with a wall in a viscous fluid. Steel and glass particles 12.7mm in diameter were used. The experiments were performed using a thick Zerodur wall (a glass-like material) with various mixtures of glycerol and water. Normal and tangential coefficients of restitution were defined from the ra...

this study simulates the temperature field and temperature stress of concrete face slabs, considering the cold waves that occur during construction as well as the contact friction between the face slabs and the cushion layer. the results show that when a cold wave occurs during construction, the surface and center temperature of the face slabs continually drop with the outside air temperature, ...

Under macroscopic pin-on-disk testing the sliding friction coefficient of Polytetrafluoroethylene (PTFE) was investigated over a temperature range of approximately 200–400 K. This study examines the nature of the temperature dependence by testing PTFE pins at varying temperature and humidity on a linear reciprocating pin-on-disk tribometer. The friction coefficient increased monotonically with ...

The main purpose of this study was to examine the effect of chalk on the friction coefficient between climber's fingers and two different rock types (sandstone and limestone). The secondary purpose was to investigate the effects of humidity and temperature on the friction coefficient and on the influence of chalk. Eleven experienced climbers took part in this study and 42 test sessions were per...

-In this paper, the effect of temperature dependent thermal conductivity on natural convection flow of viscous incompressible fluid along a uniformly heated vertical wavy surface with heat generation has been investigated. The governing boundary layer equations are first transformed into a non-dimensional form using suitable set of dimensionless variables. The resulting nonlinear system of part...

We present a theoretical study of the effect of surface defects on atomic friction in the stick-slip dynamical regime of a minimalistic model. We focus on how the presence of defects and temperature change the average properties of the system. We have identified two main mechanisms which modify the mean friction force of the system when defects are considered. As expected, defects change the po...