水舌空中左右碰撞的水力特性及其作用下的河床基岩冲刷平衡深度估算  

Hydraulic Characteristics of Water Jets by Air-Collision in Lateral Direction and Estimation on Limiting Riverbed Scour

作　　者：孙建[1] 李玉柱[2] 

机构地区：[1]西安理工大学,西安710048 [2]清华大学,北京100084

出　　处：《应用力学学报》2004年第3期134-137,共4页Chinese Journal of Applied Mechanics

基　　金：国家"九五"重点科技攻关项目 :96 2 2 1 0 5 0 1 0 2

摘　　要：应用紊动射流理论和水流动量方程 ,提出了水舌空中左右碰撞时合水舌的碰撞流速矢量、碰撞消能效率的计算公式。分析和比较了水舌空中左右碰撞与上下碰撞方式下合水舌的碰撞角 ,碰撞消能效率和其空中扩散方面的差异 ,提出了水舌空中左右碰撞作用下河床基岩冲刷平衡深度的一种估算方法。以模型实验资料验证 ,预测值和实测值基本吻合。因此表明 ,对水舌空中碰撞的水力特性分析是正确的 ,河床基岩冲刷平衡深度的估算方法是合理可行的。By applying the theory of the turbulent jet and the momentum equation to the air-collision in lateral direction of two water jets, expressions of the velocity vector of the joint jet and the colliding efficiency are proposed. Both kinds of collision in lateral direction and in up-down one of water jets are analyzed and compared to give their differences in colliding plane angle, the colliding efficiency and the air diffusion of the joint jet, and to set up a way of estimation on the limiting riverbed scour. The verification through some hydraulic model shows that the forecasted basically tallies with the measured. Thus, it is shown that such an analysis is reasonable and the estimation is feasible. Research results can be used as a reference in designing a water cushion pool acted by the water head from high dam.

关 键 词：高坝 水舌 空中左右碰撞 碰撞角 河床基岩冲刷平衡深度 

分 类 号：TV653.3[水利工程—水利水电工程]