The average bed shear stress and bed friction factor of samples with any roughness was derived from the head loss between upstream and downstream of a test section in an erosion tunnel. The method was validated in both hydraulically smooth (plexiglass; Reynolds number less than 25,000) and rough regimes (calibrated particles with known roughness). As a first step toward using this method on nat...

The purpose of this study is interested in the semi-theoretical analysis hydraulic jump evolving a rectangular straight compound channel with rough major bed. A functional relationship, non-dimensional terms, linking together different characteristics projection, obtained.

A shallow-layer model for granular flows down inclines is completed with a closure relation for the macroscopic bed friction obtained from micro-scale, discrete particle simulations of steady flows over geometrically rough bases with contact friction. Microscopic friction can be different between bulk particles and with particles at the base, where the latter is systematically varied. When exte...

Implications for flow resistance and sediment transport Michael P. Lamb* , Fanny Brun and Brian M. Fuller Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, 91125 *[email protected] Key Points: 1. Direct measurements of lift and drag forces were made on cobbles in steep flume experiments with shallow, rough flow over a planar bed 2. As flows shall...