摘要

The results of an experimental investigation of the time variation of scour width, upstream scour length and scour depth and the flow characteristics of the quasi-equilibrium state of scour a non-cohesive bed upstream of gate openings due to hydraulic differences and gate opening sizes are presented. Experiments were carried out with non-cohesive sediments for various gate openings, sediment diameter, and hydraulic differences including upstream depth. Attempts have been made to explain the main parameters affecting upstream sediment transport. The scour profiles at different times follow a particular geometrical similarity and can be expressed by a polynomial using relevant parameters. The characteristic parameters affecting the time variation of scour width, upstream scour length and scour depth are identified based on physical reasoning and a dimensional analysis. Equations for time variation of maximum scour width, upstream scour length, and scour depth are obtained empirically. A regression analysis between the measured value in a hydraulic laboratory and the predicted value in a prediction model of upstream sediment transport matched well with the determinant coefficients (r(2)) which were 0.84 for scour width, 0.89 for upstream scour length, and 0.70 for scour depth.

  • 出版日期2015-6-26

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