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The longitudinal and transverse components of flow velocity, as well as the normal and tangential stresses, must be expected to fluctuate with time and space when flow at a high Reynolds number moves between fixed boundaries. Although these nonperiodic fluctuations are generally secondary in magnitude compared to the mean motion, they have profound effects on properties of the primary mean motion. Scientists from the Illinois State Water Survey are involved in collecting and analyzing detailed velocity data from the Illinois and Mississippi Rivers using 2-D electromagnetic current meters. The goal of the present research is to understand and evaluate the turbulent structure in natural river systems, especially near...
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DWSM, the dynamic watershed simulation model, was expanded with a subsurface and a reservoir flow routing schemes. The hydrology and sediment components of the model were applied to three agricultural watersheds in Illinois, Big Ditch (100 km2), Court Creek (250 km2), and Upper Sangamon River (2,400 km2), to simulate spatially and temporally varying surface and subsurface storm water runoff, propagation of flood waves, upland soil and streambed erosion, and sediment transport; to evaluate these simulation capabilities through calibration and validation; and to conduct various watershed investigative analyses. The new schemes were selected from the literature. DWSM was able to simulate the major hydrologic, soil...
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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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The hydrodynamic characteristics of large rivers differ from those observed in smaller streams. Large rivers by nature carry substantially larger volumes of water, and their flow more closely resembles a two-dimensional pattern than does the flow of small streams. Ambient flow patterns of large rivers can be altered at least temporarily by external disturbances created by the movement of large-scale navigation traffic. Within the Upper Mississippi River System (UMRS), consisting of about 2,100 kilometers (km) including the Illinois River, navigation traffic with a geometric configuration of about 32 meters (m) by 297 m and a draft of 2.74 m can move up and down the river at speeds ranging from 0.03 to 4 or 5 meters/second...
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A pilot classification system has been developed for three trend analysis pools: 4, 8, and 13, on the Upper Mississippi River System (UMRS). Various physical parameters such as widths, radius of curvatures, and deflection angles; and attributes such as orientation of various non-main channel areas were utilized in this classification system. The techniques and the methodology developed here should be used in the classification of the entire Upper Mississippi River System. This type of classification will be needed to properly manage the system for the benefit of navigation, commerce, recreation, ecology, and the environment.
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