Author(s)

C.P. Rose & B.A. O'Connor

Abstract

The effect of enhanced turbulence levels on the magnitude of bed load transport rates is examined by computer simulations for both hydraulically smooth and rough beds. A method is demonstrated to estimate the root mean squared (RMS) bed shear stress for hydraulically rough beds. This method as well as an existing numerical integration method to calculate bed shear stresses in turbulent smooth bed conditions are used to simulate high frequency temporal shear stresses and bed load transport rates. The simulation method is shown to give similar temporally-averaged results to an existing approach of van Rijn [3] for a smooth bed. The present work suggests that reduced or enhanced shear stress fluctuations can significantly affect the magnitude of the temporally-average

Keywords