PARTICLE-VELOCITY PROFILES FOR SOLID-LIQUID FOOD FLOWS IN VERTICAL PIPES .2. MULTIPLE PARTICLES

The flow of solid-liquid mixtures is important in many food processing operations. The first paper in this group considered single-particle behaviour, and demonstrated that radial particle migration is signific ant in vertical flows. Flows of up to 10% particle concentration, usin g carrot cubes of 6 and 10 mm square flowing in (carboxymethyl cellulo se) CMC solutions, have been studied using an optical technique to ide ntify their velocity profiles in a vertical tube 44 mm in diameter. Ra dial distributions show significant differences from that which would result if particles were uniformly distributed: the effects of particl e migration can persist up to 10% solids concentration. These effects are less significant in flows of high carrier fluid viscosity.