Comparison of Characteristic Particle Velocities in Solid-Liquid Multiphase Flow in Elbow

Abstract

Abstract Erosion is a micromechanical process in which materials are removed from the inner surface of a pipe or elbow due to repeated impact of particles in multiphase flow. Measurement of particle impact velocities that causes erosive wear is complex due to spatial distribution of particles in the flow. Computational Fluid Dynamics Analysis (CFD) has been used to analyze complex flow phenomenon and particle velocities to understand the erosion behavior. CFD analysis results require experimental validation for complex flow phenomenon. The objective of the study is to compare and validate particle velocities using computational and experimental methods. Computational fluid dynamics analysis was performed for multiphase flow through an elbow to compute the particle velocities inside the elbow. Experiments were also conducted to measure the particle velocities in the elbow using a particle image velocimetry (PIV) system with similar flow conditions. The particles used were 50-micronglass beads with 2% concentration in water that flows through a 25.4 mm elbow. The flow rates used in this study were 3.5, 4.5 and 5.5 Gallons Per Minute (GPM), that corresponds to 0.436, 0.581, and 0.685 m/s velocities. The particle velocity results from CFD and PIV methods were compared to develop a better understanding of the particle impact velocities that causes erosion. The CFD predicted velocities showed good agreement with the Experimental velocity data obtained from PIV method.