Research on the Pneumatic Conveyance of Densely Concentrated Solid Particles in a Horizontal Pipe

Abstract

The conveying state of concentrated particles changes sensitively according to the local concentration of the particles, namely, with an increase of the local concentration of particles the acceleration factor of particle "k" decreases rapidly. Firstly, the new constant denoting the concentration of particles "m" modified from the mixture ratio "μ" by taking account of the specific weights and the velocities of air stream and particle, and the distribution of particles in vertical direction, is defined. Secondly, from the experimental results on the dispersed state of particles, the decreases of the acceleration factor k/k₀ are measured, where k₀ stands for the acceleration factor for a single particle. From the above investigations, the following empirical formula is obtained. [numerical formula] By using the above formula, we can presume the velocity of concentrated particles and the clogging of a pipe.