| This study represents a contribution in our understanding of the dynamics of solid/fluid turbulent motion.;For the first time measurements were performed for both the volume fraction distribution and all the turbulence parameters for solid/fluid upflow in a pipe. The particles used were 2 mm diameter spheres which had two different densities; heavier than water and lighter than water. A laser Doppler-anemometer system gave accurate measurements of the velocity, turbulence intensity, and Reynolds stresses for both the solid and liquid phases. The combination of a laser Doppler-anemometer and gamma-ray densitometer allowed the accurate determination of the local volume fraction distributions. The results represent a good benchmark test for the existing and future models.;The analysis of the problem consisted of two-phase slurry flow. The derivation of the 3-D conservation equations which govern the turbulent motion in solid/fluid flow was done. The unknown terms in these equations were constituted to achieve closure. These terms are the shear stress due to interparticle collisions, the corresponding term in the Reynolds stress equation, the force and the interfacial work term due to particle/turbulent eddies interaction. The resultant model was then evaluated using computational fluid dynamic (CFD) calculations against the experimental data. In general, good agreement was observed. The comparison between the experimental and predicted data indicates that future research should be concentrated on establishing how the particles interact with the local turbulence structure. |
