Particle Tracking Velocimetry (PTV) Measurement of Abrasive Microparticle Impact Speed and Angle in Both Air-Sand and Slurry Erosion Testers

Abstract

Solid particle laden flows are very common in many industries including oil and gas and mining. Repetitive impacts of the solid particles entrained in fluid flow can cause erosion damage in industrial equipment. Among the numerous factors which are known to affect the solid particle erosion rate, the particle impact speed and angle are the most important. It is widely accepted that the erosion rate of material is dependent on the particle speed by a power law Vn, where typically n = 2–3. Therefore, accurate measurements of abrasive particle impact speed and angle are very important in solid particle erosion modeling. In this study, utilizing a Particle Image Velocimetry (PIV) system, particle impact conditions were measured in a direct impinging jet geometry. The measurements were conducted with two different test rigs, for both air-sand and liquid-sand flows. In air-sand testing, two types of solid particles, glass beads and sharp sand particles, were used. The measurements in air-sand tests were carried out using particles with various sizes (75, 150, and 500 μm). Also, submerged testing measurements were performed with 300 μm sand particles. In the test conditions, the Stokes number was relatively high (St = 3000 for air/sand flow, St = 27 for water/sand flow), and abrasive particles were not closely following the fluid streamlines. Therefore, a Particle Tracking Velocimetry (PTV) technique was employed to measure the particle impact speed and its angle with the target surface very near the impact. Furthermore, Computational Fluid Dynamics (CFD) simulations were performed, and the CFD results were compared with the experimental data. It was found that the CFD results are in very good agreement with experimental data.