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Role of near-bed turbulence in bedload transport

Jonathan M. Nelson·Ronald L. Shreve·Stephen R. McLean
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Abstract

Bedload transport by a turbulent fluid moving over an erodible sediment bed results from complex interactions between flow field of the overlying fluid and the grains making up the bed. To develop a better view of these interactions, a method that combines high-speed photography with laser-Doppler velocimetry was devised. The methodology permits correlation of bedload transport with local turbulence structure at a frequency resolution of 10 hz. By making a suite of measurements at varying distances from a backward step, data were obtained for a variety of flows with different turbulence characteristics ranging from steady, uniform boundary layers to highly intermittent, nonuniform wake-like flows.

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Jonathan M. Nelson, Ronald L. Shreve, Stephen R. McLean. 1995. Role of near-bed turbulence in bedload transport. https://pubs.usgs.gov/publication/70018825

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