Water-sand two-phase flow and wear characteristics in a rotating jet wear device at different impact angles

Abstract

The characteristics of water and sand two-phase flow and their wear features in a rotating jet wear device at various impact angles are investigated by the wear weight loss test, spraying paint abrasion distribution experiment and numerically multiphase simulation. The results reveal that the weight loss of specimen abrasion initially increases and then decreases as the impact angle rises, peaking at about 40°. The annular abrasion distribution on the test disk can be obtained by the simulation model which adopts the slip grid method to handle the rotation of disk, aligning well with experimental results. Furthermore, the abrasion distribution and weight loss predicted by the Oka abrasion model and the Grant and Tabakoff (G&T) collision rebound model closely match the experimental data. At lower impact angles (15°–45°), the jet velocity is low while the rotational speed is high, and the two-phase jet flow spreads towards the specimen’s outer edge due to centrifugal force, which results in the increased wear on the specimens with the disk’s radius. At the impact angle of 60°, high abrasion rate strip is observed near the specimen’s centerline in both the paint spray test and numerical simulation. At this angle, the jet collides with the rotating wall and generates a spiral trajectory along the circumferential position of the disc, forming vortices at the downstream of the nozzle. The particle aggregate inside the vortices, forming high sediment concentration distribution and high wear rate strip on the specimen. This work will establish a foundation for the simulation and testing of sediment wear in hydraulic machineries.