this study is concerned with the prediction of particles’ velocity in a dilute turbulent gas-solidboundary layer flow using a fully eulerian two-fluid model. the closures required for equationsdescribing the particulate phase are derived from the kinetic theory of granular flows. gas phaseturbulence is modeled by one-equation model and solid phase turbulence by mlh theory. resultsof one-way and...

We present a simple model for the friction of two solid bodies moving against each other. In a self consistent way we can obtain the dependence of the macro-scopic friction force as a function of the driving velocity, the normal force and the ruggedness of the surfaces in contact. Our results are discussed in the context of friction laws used in earthquake models.

placed on the oxidation of choline to betaine via betaine aldehyde which is catalysed by the choline oxidase system. Recent research has indicated that this pathway may indeed be very important for the scavenging of methyl groups from choline 12 I. T h e catabolism of betaine produces one-carbon fragments ;IS ;I result of the sequential demethylation o f betaine to form glycine. T h e first ste...

The problem of the onset and growth of solid tumour in homogeneous tissue is regarded using an approach based on local interaction between the tumoral and the sane tissue cells. The characteristic sizes and growth rates of spherical tumours, the points of the beginning and the end of spherical growth, and the further development of complex structures (elongated outgrowths, dendritic structures,...

A general adsorption model is developed to describe the interactions between near-wall fluid molecules and solid surfaces. This model serves as a framework for the theoretical modelling of boundary slip phenomena. Based on this adsorption model, a new general model for the slip velocity of fluids on solid surfaces is introduced. The slip boundary condition at a fluid-solid interface has hithert...

abstractthe purpose of this study was to investigate the controllable operating parameters influence, including ph, solid content, collector, co-collector, and depressant dose, and conditioning time, on apatite flotation kinetics. four first order flotation kinetic models are tested on batch flotation time-recovery profiles. the results of batch flotation tests and the fitting of first-order ki...

In this paper, the reflection and refraction of longitudinal wave from a plane surface separating a micropolar viscoelastic solid half space and a fluid saturated incompressible half space is studied. A longitudinal wave (P-wave) impinges obliquely at the interface. Amplitude ratios for various reflected and transmitted waves have been obtained. Then these amplitude ratios have been computed nu...