Effect of Particle Size on Magnitude and Location of Maximum Erosion in S-Bend

Solid particle erosion is a micromechanical process that is influenced by flow geometry, material of the impacting surface, impact angle, particle size and shape, particle velocity, flow condition and fluid properties. Among the various factors, particle size and velocity have been considered to be the most important parameters that cause erosion. Particle size and velocity are influenced by surrounding flow velocities and carrying fluid properties. Higher erosion rates have been observed in gas-solid flow in geometries where the flow direction changes rapidly, such as elbows, tees, valves, etc., due to local turbulence and unsteady flow behaviors. S-bend geometry is widely used in different fluid handling applications such as automotive, oil and gas, arteries and blood vessels. This paper presents the results of a Computational Fluid Dynamic (CFD) simulation of diluted gas-solid and liquid-solid flows through an S-Bend and the dynamic behavior of entrained solid particles in the flow. CFD analyses were performed at five different particle sizes ranging between 50 and 300 microns. Maximum erosive wear was observed at smaller particle sizes and compared to the larger sizes. The location of maximum erosion was at different locations in the first bend as compared to the second bend.