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Turbulent characteristics of flow velocity in a natural river were systematically analyzed in this study. Flow velocities were measured with time at six different lateral locations and at three different vertical elevations on a major navigable waterway in the United States. Analyses of the velocity data include the cross-sectional and vertical distributions of longitudinal and transverse velocity components (u, v), the fluctuating velocity components (u1, v1) and their frequency-distribution curves, turbulent intensities (�x'�y), and turbulent shear stress (scientific formula not reproduced). These analyses have shown that the strongest velocity fluctuation occurs near the main channel area above the river bed.
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Movement of navigation traffic such as barge tows within a restricted inland waterway such as the Illinois, Mississippi, or Ohio Rivers can and will alter the flow field in and around the moving vessel. These changes in the flow field will include altered velocity distributions, increase and/or decrease in the pressure field, and a directional change of the flow within the zones of return flows. Normally, as a barge-tow configuration of about 105 feet by 1,100 feet in surface area and a 9-foot draft moves within a river cross section of about 800 feet by 12 feet, significant changes on the flow field occur. River traffic such as this can also generate waves and drawdown, which sometimes range from a few inches to...
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Movement of barge traffic (barge tows) in restricted waterways such as the Illinois or Mississippi Rivers can generate rapid return flows and water-level depressions (drawdown) between the barge and the shoreline. Due to this return flow, velocity distribution in the zone between the barge and the shore changes temporarily in space and time. The return velocity and the drawdown generated by barge traffic depend on many factors, including river width and depth, barge characteristics, tow speed, draft, and lateral distance from the barge to the shore. An overall mathematical modeling concept of the lateral variation of return flow due to navigation traffic is discussed in this paper. The x- and y-components of velocity...
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Turbulence characteristics of ambient flow velocities and their comparison with those generated by the movement of barge traffic within the channel border area in a navigation waterway are discussed in this paper. The ambient velocity and the changes of velocity due to barge traffic are being continuously measured with time at three distances from the shore on one side of the Illinois River near McEvers Island. The analysis of velocity data includes the longitudinal and lateral components of velocity, turbulence intensities u' and v', and the variation of Reynolds stress (-pUV) with time. The lateral variations of Reynolds stress distributions (-pUV) for the ambient velocity and the velocity due to the movement...
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This report summarizes the investigation conducted by the Illinois State Water Survey on the physical changes associated with the movement of navigation traffic on the Illinois and Upper Mississippi Rivers. This research project was partially funded by the Environmental Management Technical Center of the U.S. Geological Survey and the U.S. Army Corps of Engineers. Project activities were conducted through the Illinois Department of Natural Resources. Research results have also been presented at technical society meetings and published in a number of journals.
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