The transition to convection in a zero Prandtl number fluid with stress-free and perfectly conducting boundaries differs significantly from finite Prandtl number convection, giving rise to a three-dimensional pattern. Two possible scenarios are described and compared with recent numerical simulations by Thual Ii]. The Prandtl number of a fluid can approach zero in one of two ways either because...

Densities, structural effects and viscosities of binary nonelectrolyte systems including nitrobenzene + 2-propanol, 2-butanol and 2-pentanol at temperatures (293.15 to 323.15) K and normal atmospheric pressure were measured using an Anton-Paar SVM 3000 stabinger viscometer. Excess molar volumes  and viscosity deviations Δη were calculated and correlated by the Redlich-Kister equation t...

micro scale gas flows has attracted significant research interest in the last two decades. in this research, the fluid flow of gases in the stepped micro-channel at a wide range of knudsen number has been analyzed with using the lattice boltzmann (mrt) method. in the model, a modified second-order slip boundary condition and a bosanquet-type effective viscosity are used to consider the velocity...

S U M M A R Y Global circulation models are analysed using a temperature and strain-rate dependent rheology in order to refine previous estimates of the nature of mantle flow and plate driving forces. Based on temperature inferred from a tectonic model and seismic tomography, the suboceanic viscosity is lower than underneath continents by ∼ one order of magnitude. If net-rotations of the lithos...

a r t i c l e i n f o a b s t r a c t Keywords: viscosity lower mantle mantle plume elasticity spin transition A proper determination of the lower-mantle viscosity profile is fundamental to understanding Earth geodynamics. Based on results coming from different sources, several models have been proposed to constrain the variations of viscosity as a function of pressure, stress and temperature. ...

Nonlinear conservation laws with moving boundaries often arise in applications such as gas and plasma dynamics and more recently in the context of nuclear fusion reactors. Gaining insight into the nature of solutions to such models and their dependence upon design parameters is often done numerically. Instead of relying upon numerics, in this paper we use formal asymptotics to study a model of ...

This study presents a novel pressure-based methodology for the efficient numerical solution of four-equation two-phase diffuse interface model. The proposed has potential to simulate low-Mach flows with mass transfer. In contrast classical conservative model formulation, adopted set equations features volume fraction, temperature, velocity and pressure as primary variables. includes effects vis...

The viscosities of two prototypical glass formers, o-terphenyl and phenyl salicylate (salol), are shown to exhibit a change in their temperature and pressure dependences at a constant value of the viscosity. This is the first evidence of a dynamic crossover in the viscosity induced by pressure. The characteristic value associated with the change in dynamics is material dependent, but independen...

the density and viscosity values at t= (293.15 to 323.15) k for binary mixtures of nitromethane with 2-propanol, 2-butanol and 2-pentanol were measured over the entire composition range. from the experimental data, excess molar volumes, thermal expansion coefficients, excess thermal expansions, partial molar volumes at infinite dilution and deviations in viscosity were calculated. the results w...

density, viscosity and refractive index of pure, binary and ternary mixtures of diethanolamine (dea) and methyl diethanolamine (mdea) with water have been measured at different temperatures from 288.15 k to 323.15 k at atmospheric pressure. also, this study presents the effects of mixture composition and temperature upon these thermo- physical properties. to measure the density and refractive i...