Relation between Mean and Maximum Velocities in a Natural River

Abstract

The cross-sectional mean velocity is an important variable in open-channel hydraulics, whereas the maximum velocity in a channel cross section is mentioned very little. However, the maximum velocity in a channel cross section might be as important as the cross-sectional mean velocity. This is because the measurable maximum velocity can be considered as a “signal,” from which one can know the range of the velocity in a channel cross section. This study explored the relation between the cross-sectional mean and maximum velocities in a natural river by using velocity data collected from the Mississippi River. The relation of the maximum velocity to the cross-sectional mean velocity on different straight reaches in the Mississippi River is perfectly linear. The relation of the maximum velocity to the cross-sectional mean velocity on different river bends is still linear and changes with the