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研究了矩形平底明渠淹没水跃区的水头损失。根据Rajaratnam对淹没水跃区的流速分布、壁面切应力、最大流速的试验成果和Verhoff附壁射流区断面流速分布的计算公式,应用紊流边界层理论研究了淹没水跃区的边界层发展和沿程水头损失的计算方法。根据动量方程和能量方程研究了淹没水跃区的跃前断面水深、总水头损失、局部水头损失、消能率的计算方法。给出了淹没水跃区最大流速、紊流边界层厚度、沿程水头损失、总水头损失、局部水头损失、局部阻力系数、消能率的计算方法。研究表明:淹没水跃区的总水头损失是跃前断面弗劳德数、跃前水深和淹没度的函数,沿程水头损失和局部水头损失与跃前断面流速、水深、水跃长度、跃前断面的特征雷诺数和消力池宽度有关。淹没水跃区的水头损失主要是局部水头损失,消能率随着弗劳德数的增加而增加。
The water head loss in the submerged aquaplane area with rectangular flat bottom and open channel was studied. According to Rajaratnam’s calculation formula of velocity distribution, wall shear stress, maximum flow velocity and flow velocity distribution in Verhoff attachment zone, the application of turbulent boundary layer theory to the development of boundary layer in submerged hydrojunction area Calculation of head loss along the way Based on the momentum equation and energy equation, the calculation method of water depth, total head loss, local head loss and energy dissipation ratio in the submerged aquatic region was studied. The calculation methods of the maximum flow velocity, the thickness of the boundary layer, the head loss, the total head loss, the local head loss, the local resistance coefficient and the energy dissipation rate are given. The results show that the total head loss in flooded area is a function of Froude number before jump, water depth and submergence before jump, head loss and local head loss and flow velocity, water depth and water jump length The characteristic Reynolds number of the front section is related to the width of the stilling pool. The water head loss in flooded area is mainly caused by local head loss, and the energy dissipation rate increases with the increase of Froude number.