Effect of particle density and inflow concentration of suspended sediment on bedload transport in rill flow

摘要: Laboratory flume experiments were carried out to evaluate the effect of particle density on bedload transport sand-sized particles and a suspended load clay (kaolinite) in rill flow conditions. Three materials range 400–600 μm selected simulate primary aggregates: sand (2650 kg/m3), crushed brick (2450 kg/m3) anthracite (1300–1700 kg/m3). In two first experiments, different methods applied determine capacity coarse for various conditions discharge (from 2 15 L/min) slope (2.2, 3 4%). third experiment, clear water was replaced with kaolinite–water mixture determined 4% concentrations kaolinite (0, 7, 41 84 g/L). The results showed that increased significantly decrease but rates much less important than discharge. Velocity measurements flow, mixed confirmed existence differentiation between bedload. these experimental conditions, did not affect particles. formulae tested against observed rates. A calibration Foster formula revealed shear stress exponent should be greater 1.5. Low Govers unit stream power (USP) equations then evaluated. equation preferred prediction it recommended case aggregates low because limited derive this equation. Copyright © 2008 John Wiley & Sons, Ltd.