Experimental and Numerical Simulation Analyses of the Interaction between Fine-grained Sediments and Low-velocity Water Flow: A Case Study of the Alar Section in the Upper Tarim River

This study examined the water–sediment feedback mechanisms of fine sediment (۰.۱–۰.۳ mm) in the upper reaches of the Tarim River under low-flow velocities (۰.۱۲–۰.۳۲ m/s) through a combination of flume experiments and Eulerian two-phase flow simulations in Fluent. The standard k-ε turbulence model was employed to systematically evaluate nine conditions representing three sediment sizes and three flow velocities. The results show that (۱) when the particle size is less than ۰.۲ mm and flow velocity is ۰.۱۲ m/s, the sediment remains under uniform settling condition; when the particle size exceeds ۰.۲ mm, deposition accumulates; and when the flow velocity exceeds ۰.۱۲ m/s, deposit thickness decreases. (۲) The flow velocity primarily controls sediment transport intensity, whereas particle size ≥ ۰.۲ mm significantly alters the turbulent structure of the flow. (۳) When the flow velocity is ≥۰.۲۲ m/s and particle size is ≥۰.۲ mm, turbulent kinetic energy in the sediment settling zone increases by an additional ۷.۲۳%, indicating a synergistic enhancement effect.

کلیدواژه ها:

Fine sediment ، Water&ndash ، sediment coupling ، Deposition characteristic ، Flow velocity response ، Turbulence Kinetic Energy