摘要

A novel particle tracking velocimetry (PTV)/computational fluid dynamics (CFD) hybrid method for measuring coefficient of restitution (COR) has been developed which is relatively simple, cost-effective, and robust. A laser and camera system is used in the Virginia Tech Aerothermal Rig to measure velocity trajectories of microparticles. The method solves for particle impact velocity at the impact surface using a CFD solution and Lagrangian particle tracking. The methodology presented here attempts to characterize a difficult problem by a combination of established techniques, PTV and CFD, which have not been used in this capacity before. Erosion and deposition are functions of particle/wall interactions and COR is a fundamental property of these interactions. COR depends on impact velocity, angle of impact, temperature, particle composition, and wall material. Two sizes of Arizona road dust and one size of glass beads are impacted on to a 304 stainless steel coupon. The particles are entrained into a free jet of 27 m s(-1) at room temperature. Impact angle was varied from 85 degrees to 25 degrees depending on particle. Mean results collected using this new technique compare favorably with trends established in literature. The utilization of this technique to measure COR of microparticle sand will help develop a computational model and serve as a baseline for further measurements at elevated air and wall temperatures.

  • 出版日期2013-10