S型水跃局部水头损失系数与跃后水深计算方法

鉴于水跃跃后水深作为消力池体形设计的重要参数,通过建立水跃区跃前和跃后断面的能量方程,分析了突扩式消力池S型水跃局部水头损失系数和共轭水深比的变化规律。研究发现,S型水跃相对局部水头损失系数是跃前断面弗劳德数函数,并随着弗劳德数的增大而增大;相对局部水头损失系数随跃前断面弗劳德数的变化规律既可用线性公式表示又可用乘幂公式表示;水跃共轭水深比是跃前断面弗劳德数和消力池突扩比的函数。通过能量方程求解的S型水跃跃后水深公式具有较高的计算精度和较好的通用性,且能作为矩形明渠水跃共轭水深的求解公式。

Calculation of Local Head Loss Coefficient and the Sequent Depth of S-type Hydraulic Jump

The sequent water depth of hydraulic jump is an important parameter for shape design of stilling basin. The change rule of the local head loss coefficient and the conjugate depth ratio occurring in an abruptly expanding stilling basin were analyzed based on energy equation. It is shown that the relative local head loss coefficient of S-type hydraulic jump is the Froude number in the upstream jump section, and increases with the increase of the Froude number. The relationship between them obeys linear distribution and exponentiation distribution. The conjugate depth ratio is the function of upstream Froude number and abruptly expanding ratio. The equation of the sequent depth of S-type hydraulic jump which obtains from energy equation has higher calculation accuracy and good generality. Furthermore, the above equation can be used to solve the conjugate depth of rectangular open-channel hydraulic jump.