导流兼泄洪洞泄流能力计算

Discharge Capacity Calculation of Diversion and Spillway Tunnels

泄洪系统是水库电站建筑物的重要组成部分,承担泄洪任务,一般由表孔及底孔组成,其最小结构尺寸由泄洪时的特征水位及所需要下泄的流量确定。针对有压导流兼泄洪洞(即底孔)进行水力学计算,有压洞泄流量由出口工作弧门控制,采用有压洞泄流公式计算确定出满足最大泄流要求所需要的最小结构尺寸,在此基础上,当出口工作弧门局部开启时,同时采用闸孔出流公式及有压洞泄流公式分别进行计算不同水位、开度及所对应的流量值,并将其与物理模型试验结果进行对比。分析表明在弧门局部开启时采用闸孔出流公式计算出的结果与模型试验结果一致性较好,其结果可以为类似工程水力学计算提供实践参考。

The release flood water system is an important part of reservoir power station buildings, it has operated for the purpose of whole project discharge, generally composed of upper and bottom outlets, its minimum structure size is determined by the reservoir characteristic stage and water release when flood is discharged. The Flood-discharge tunnel （bottom hole） is the pressure tunnel which was diversion used in the construction period,and its flow was controlled by service radial gate at the exit of the tunnel. In this paper, the discharge capacity of the flood-discharge tunnel is calculated through two formulas, one is pressure hole discharge formula, the other is brake orifice discharge formula. On the basis of the minimum size of the bottom, the outlet is determined by the pressure hole discharge formula, when the arc gate under local opening conditions, in different water levels and exits of different openings, the flow is calculated by the two formulas, and the results are compared with those of the physical model test. Analyses indicate that the arc door opened by the local gate orifice flow formula of the calculated results and the model test results are in good agreements, and the results can be provided for the similar engineering hydraulic calculation reference for practice.