Direct measurements of lift and drag on shallowly submerged cobbles in steep streams: Implications for flow resistance and sediment transport
نویسندگان
چکیده
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 shallow, drag coefficients increase, turbulent fluctuations decrease, and lift forces are negative, pulling particles to the bed 3. Results help explain high flow resistance, high critical Shields numbers, and low sediment transport rates in mountain streams
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