The liquid filament microrheometer originally described by Bazilevsky et al. (1990) provides a simple way of extracting material parameters for Newtonian and viscoelastic fluids from measurements of the capillary breakup of a thin fluid thread. However, there is an unresolved discrepancy in the value of the Newtonian viscosity obtained from the experimental data when using the existing theoreti...

The excellent performance of fluidized bed heat exchangers is due to the interaction between particles and heat transfer surface and to the mixing effects in the viscous sublayer. In this paper, the results of experimental investigations on heat transfer for a wide range of Newtonian and non-Newtonian (shear-thinning power law) fluids are presented. New design equations have been developed ...

In this paper, a symmetry particle method, the smoothed particle hydrodynamics (SPHs) method, is extended to deal with non-Newtonian fluids. First, the viscous liquid is modeled by a non-Newtonian fluid flow and the variable viscosity under shear stress is determined by the Carreau-Yasuda model. Then a pressure correction method is proposed, by correcting density error with individual stiffness...

The presence of particles in liquid-solid fluidized beds enhances the bed heat transfer, because the movement of the particles leads to an increased turbulence in the system. Moreover, the violent movement of the particles has a positive effect on fouling of the heat transfer surface. The aim of this investigation was to perform systematic measurements of bed voidage and heat transfer coeff...

A numerical method for simulating the extensional dynamics of elongating ®laments of non-Newtonian ̄uids in a ®lament stretching rheometer is presented. The boundary element method, in conjunction with either the Oldroyd-B or the generalized multimode Upper-Convected Maxwell constitutive model, is used to calculate the transient evolution of the liquid interface, the applied force on the station...

Experimental observations are reported for the laminar flow of a viscoelastic liquid through a symmetrical plane sudden expansion preceded by a gradual contraction from a square duct. As is well known, for Newtonian fluid flow above a critical Reynolds number the flowfield downstream of an expansion becomes asymmetric. For the viscoelastic liquid investigated here the asymmetry is greatly reduc...

Deformation and breakup of a viscous drop in a Bingham liquid is investigated numerically with a volume-of-fluid scheme. Initially, a spherical drop is placed between two moving parallel plates. For our parameters, the matrix liquid has yielded. The competing effects driving the motion are the shear and interfacial tension. When interfacial tension effects dominate, the drop evolves to a steady...

Quartz crystal impedance analysis has been developed as a technique to assess whether room-temperature ionic liquids are Newtonian fluids and as a small-volume method for determining the values of their viscosity-density product, rho eta. Changes in the impedance spectrum of a 5-MHz fundamental frequency quartz crystal induced by a water-miscible room-temperature ionic liquid, 1-butyl-3-methyli...

A temporal stability analysis was carried out to model the atomization of a swirling viscous non-Newtonian annular liquid sheet emanating from an air-blast atomizer subject to inner and outer inviscid swirling air streams. The dimensionless dispersion equation that governs the instability of a viscous non-Newtonian annular liquid sheet under swirling air streams was obtained. Numerical solution...