Study of the characteristics of fan-shaped impact jets during high-pressure water scale removal

Abstract

The jet characteristics of the nozzles in high-pressure water scale removal systems are crucial to the quality of scale removal. The effects of different turbulence models, Reynolds numbers, and target distances on jet velocity, pressure, water volume, shear force, and descaling width and thickness in the free jet, wall jet, and stagnation zones were studied and compared with experimental data. It is found that the simulation results of the renormalization group (RNG) k-ε model are more closely matched to the experimental results. When the jet reaches approximately z = − 40 de, the velocity and dynamic pressure rapidly decay. The volume of water on the jet axial line gradually decreases at z = 0 to − 40 de. As the jet gradually approaches the surface of the slab, the peak and trough values of the vertical velocity along the striking force line near the wall gradually decrease. As the target distance increases, the volume of jet water, impact pressure, and wall shear gradually decrease, and the jet width gradually increases. As the Reynolds number increases, the volume of the jet water changes less, and the impact pressure and wall shear force increase rapidly. When the descaling pressure is 16 MPa, the impact force of the jet cannot meet the requirements of descaling. Based on research content, a dimensionless functional relationship between descaling width, thickness, strike pressure, target distance, and Reynolds number has been established.