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USGS · 70189356

Topographic evolution of sandbars: Flume experiment and computational modeling

Paul J. Kinzel·Jonathan M. Nelson·Richard R. McDonald·Brandy L. Logan
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Abstract

Measurements of sandbar formation and evolution were carried out in a laboratory flume and the topographic characteristics of these barforms were compared to predictions from a computational flow and sediment transport model with bed evolution. The flume experiment produced sandbars with approximate mode 2, whereas numerical simulations produced a bed morphology better approximated as alternate bars, mode 1. In addition, bar formation occurred more rapidly in the laboratory channel than for the model channel. This paper focuses on a steady-flow laboratory experiment without upstream sediment supply. Future experiments will examine the effects of unsteady flow and sediment supply and the use of numerical models to simulate the response of barform topography to these influences.

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Paul J. Kinzel, Jonathan M. Nelson, Richard R. McDonald, Brandy L. Logan. 2010. Topographic evolution of sandbars: Flume experiment and computational modeling. https://pubs.usgs.gov/publication/70189356

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