Abstract：In order to study energy dissipation characteristics of stepped spillway, the water head along a stepped spillway is compared with that along a smooth spillway, and a relative hydraulic head concept is introduced in this paper. Three engineered stepped spillway models are measured with slope in range of 1 ∶2.0-1 ∶0.9 and step height ranged in 0.5-2.0 m. The effects of length of flow path, unit discharge, step height and slope on the relative head are studied. The experimental results show that the relative head all along the spillway is less than zero, indicating that the flow energy along a stepped spillway is lower than a smooth spillway. The relative head has a linear relationship with the length of flow path that is subject to a correlation coefficient between 0.998 3 and 0.999 8. The relative head has nothing to with the unit discharge, as a result, the head in the same section is nearly constant at different discharges with an equal or less than 4.5% relative error in comparing with the straight line slope. The step height and slope have a great influence on the relative head, especially, the higher the step height and the steeper the slope, the greater the absolute value of relative head. The experimental data confirm that the relative head of a stepped spillway varies regularly, and it is convenient for practical application and analysis, and also can provide a reference for the design of stepped spillway..
文明宜, 刘韩生, 范灵芝, 柳思源. 台阶式溢洪道滑行水流的相对水头[J]. 排灌机械工程学报, 2016, 34(5): 414-417.
WEN Mingyi, LIU Hansheng, FAN Lingzhi, LIU Siyuan. Relative water head of skimming flow over stepped spillways. Journal of Drainage and Irrigation Machinery Engin, 2016, 34(5): 414-417.
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