TURBULENCE INTENSITY IN DILUTE 2-PHASE FLOWS .1. EFFECT OF PARTICLE-SIZE DISTRIBUTION ON THE TURBULENCE OF THE CARRIER FLUID

We deal with the effect of particle size and concentration on the inte nsity of turbulent fluctuations in two-phase flows. An interaction bet ween polydisperse particles and the turbulence of the carrier fluid is considered. The theoretical analysis of that process is based on Pran dtl's mixing-length theory, modified to account for the peculiarities of the viscous interaction of small particles and carrier fluid as wel l as an effect of the admixture inertia. For a particle-laden flow wit h a bidisperse particle-size distribution, the intensity of turbulent fluctuations of the particles and fluid is determined as a function of the particles sizes and their mass contents. It is shown that at a fi xed total mass content of the admixture, the turbulence intensity in p olydisperse flow is essentially different from that in monodisperse fl ow. Some results on the turbulence properties of a turbulent particle- laden jet with a polydisperse admixture are obtained.