OBJECTIVES This study evaluated the effect of refrigeration at 4 degrees C and post-refrigeration times (immediate, 5, 10, 15, or 20 min) on the viscosity and conversion kinetics of adhesive bonding resins. METHODS Scotchbond Dual-Cure (3M ESPE) and Clearfil SE Bond (Kuraray) were tested. Control samples were kept at 25 degrees C for 24 h. At each post-refrigeration time, the temperature was ...

Thermal spray has traditionally been used for depositing metallic, carbide and ceramic coatings, however, it has recently been found that the high kinetic energy of the High Velocity Oxy-Fuel (HVOF) thermal spray process also enables the solventless processing of high melt viscosity polymers, eliminating the need for harmful, volatile organic solvents. A primarily goal of this work was to devel...

Effect of temperature-dependent viscosity on fully developed forced convection in a duct of rectangular cross-section occupied by a fluid-saturated porous medium is investigated analytically. The Darcy flow model is applied and the viscosity-temperature relation is assumed to be an inverse-linear one. The case of uniform heat flux on the walls, i.e. the H boundary condition in the terminology o...

Abstract. In this work, we study the unsteady axisymmetric mixed convection boundary layer flow and heat transfer of non-Newtonian power law fluid over a cylinder. Different from most classical works, the temperature dependent variable fluid viscosity and thermal conductivity are taken into account in highly coupled velocity and temperature fields. The motion of the fluid can be modeled by a ti...

One of the more enigmatic features of the Earth’s style of mantle convection is plate tectonics itself, in particular the existence of strike-slip, or toroidal, motion. Toroidal motion is uncharacteristic of basic thermal convection, but necessarily forms through the interaction of convective flow and nonlinear rheological mechanisms. Recent studies have implied that the empirically determined ...

The principle, that the rate of internal viscous dissipation is at a minimum, is incorrect when temperature and velocity fields are linked through temperature-dependent viscosity or density. This makes it inappropriate for the study of spreading ridge – transform fault systems or other plate-tectonic problems with large density stratification resulting from large temperature gradients. Correcti...

In the present work, a mathematical model is developed and analyzed to study the influence of nanoparticle concentration through Brownian motion and thermophoresis diffusion. The governing system of PDEs is transformed into a coupled non-linear ODEs by using suitable variables. The converted equations are then solved by using robust shooting method with the help of MATLAB (bvp4c). The impacts o...

The rheological characteristics of digested sludge are severely temperature dependent. An effect of temperature on rheological properties of digested sludge is partially irreversible. In this paper, the effects of temperature change and thermal history on viscosity of digested sludge were studied using a stress-controlled rheometer which was connected to a temperature controlled water bath. Dig...

Viscosity, a key property for glass processing, is a function of glass composition and temperature. Nuclear waste glasses must be formulated to obtain a desired viscosity at the melter processing temperature for each waste composition to be vitrified. Over the past decades, a large viscosity database has been accumulated at various laboratories in the US. The database, compiled at the Pacific N...

This article proposes spectral numerical methods to solve the time evolution of convection problems with viscosity strongly depending on temperature at infinite Prandtl number. Although we verify the proposed techniques just for viscosities that depend exponentially on temperature, the methods are extensible to other dependence laws. The set-up is a 2D domain with periodic boundary conditions a...