Basic Studies on Hydraulic Capsule Transportation : Part 1. Loss due to Cylindrical Capsules Set in Circular Pipe Flow

Abstract

On the loss due to cylindrical model capsules set in the flow of circular section pipe, an experimental investigation was carried out in the ranges of 5×10²∼3×10⁴ in Reynolds number and 0.64∼0.92 in the diameter ratio. The main results obtained are as follows : (1) The friction factor λ_m in eccentric annuli having unit eccentricity depends on Reynolds number Re_m and the diameter ratio K and is expressed as [numerical formula] where n is 1 in the laminar flow and n is 1/4 in the turbulent flow. (2) The inflow contraction factor ζ_i and the outflow expansion factor ζ_e are dependent on Reynolds number and the diameter ratio respectively and ζ_i is larger than ζ_e. (3) The additional loss factor due to capsule η_c decreases with an increase in Reynolds number Re in the range of Re>5×10³ and at a given Reynolds number, it increases with an increase in the diameter ratio and the length diameter ratio of capsule.