密排加糙床面消力池自由水跃跃长计算

摘要

As the important parameters in designing the stilling basin, calculation of the length of the free hydraulic jump plays a major role in the safety, stability and economization for the stilling basin. The research on the variation laws of the vortex roll length of the free hydraulic jump and the hydraulic jump length occurred on the uniform rough height bed of the stilling basin was carried out according to establishing the motion equations for water body particle in the hydraulic jump zone, and developing a theoretical method for calculation of the vortex roll length of the free hydraulic jump and the hydraulic jump length, and the physical parameters are calibrated by the given expressions based on the testing data from the existing literatures. Research results show that both of the hydraulic jump vortex roll length and the hydraulic jump length on the uniform rough height bed of the stilling basin increase with the increase of the upstream Froude number, upstream supercritical water depth and the conjugate depth ratio, and at the same time decrease with the increase of the equivalent roughness of the riverbed. From the verification results it is found that the calculated values are well approximate to the measured values of the hydraulic jump vortex roll length and the hydraulic jump lengths.%水跃长度作为消力池设计的重要参数，对消力池安全稳定以及经济合理的影响效果显著。通过建立水跃区水体质点的运动方程，研究密排加糙床面消力池水跃旋滚长度和水跃长度的变化规律，提出了水跃旋滚长度和水跃长度计算的理论方法，并根据已有文献的试验数据对所推公式涉及的物理参数进行率定。计算研究结果表明，密排加糙床面消力池水跃旋滚长度和水跃长度均随跃前断面弗劳德数、跃前断面水深和水跃共轭水深比的增大而增大，随着床面当量粗糙高度的增加而减小。经验证发现，水跃旋滚长度和水跃长度的计算值与实测值接近。