射流冲刷平衡深度研究

Study on equilibrium scour depth of impinging jet

本文通过水槽实验和理论分析,研究了在水流速度低、泥沙易淤积的区域引入平面冲击射流对消除泥沙淤积的影响。实验观测了射流局部达到冲刷平衡时,最大冲刷深度随射流喷口高度、喷口宽度、喷口流速、横流流速及泥沙特性变化的规律。由泥沙起动理论和平面射流运动规律,建立了射流冲刷平衡深度计算式。用不同性质的泥沙和采用不同射流喷口宽度、不同喷口高度的射流冲刷实验资料对建立的计算公式进行了验证,计算结果与实验资料吻合良好。

In this paper, the effects of the water impinging jet on the local scour equilibrium depth were studied through laboratory experiments and theoretical analysis. The experiments were conducted by inducing jet into flume flow, in which the flow velocity was low and the sediments were easily deposited. The variations of the local scour equilibrium depth with the pa-rameters of the jet, such as jet exit height, width, velocity and sediments characteristics, were observed in the experiments. Based on the theory of sediment particle incipient motion and the jet flow movement transport, a formula for calculating the e-quilihrium depth scoured by impinging jet was established. The calculated results were compared and in good agreement with the experiments' ones.