Particle dynamic behaviors in bubble curtain barriers blocking the diffusion of sediment

Abstract

Bubble curtains are linear multiphase plumes that are used in industry and engineering to reduce diffusive flows between two zones. The circulating shear flow generated by the bubble plume can effectively create a particle barrier in the water; thus, it is also widely used to suppress the diffusion of suspended particles during dredging operations. To clarify the interaction mechanism between the bubble curtain and suspended particles under pressure-driven flow, experimental studies and numerical simulations were conducted to investigate the particle dynamics in the flow field around the bubble curtain. In this study, we established a formal analogy between a bubble curtain and an air curtain and qualitatively identified four typical distribution zones of the particles in the flow field. Based on the quantitative measurements and theoretical considerations, the optimal operating conditions and the upper limit of effectiveness of the bubble curtain were determined. In addition, the blocking behavior and efficiency of bubble plumes on particles with different ReU and FrUgnumbers and different particle properties were simulated via the computational fluid dynamicsdiscrete element method (CFDDEM) numerical simulation method.