折流坎高度对导流洞交汇段水力特性的影响

Influence of Baffle with Different Heights on Flow State of Rebuilt Conduit

针对竖井旋流泄洪洞与原导流洞交汇段后水流冲顶、流态紊乱的问题,结合某导流洞改建工程,通过水工模型试验,研究了不同高度折流坎对交汇段后水力特性的影响。结果表明,随着折流坎高度的降低,折流坎压强增大,最大压强均出现在上游侧;随着折流坎高度的降低,导流洞内的水流逐渐平顺;增设折流坎后,交汇段的局部水头损失降低了8.627%~15.063%,且折流坎高度降低,局部水头损失减小。综合考虑发现设计工况下体型d(折流坎高度约为1.05倍的来流水深)相对较优。研究结果可为类似工程提供参考。

In order to solve the problem that the flow top and flow state are disorder after the intersection section of the shaft swirling flood discharge tunnel and the original diversion tunnel,combined with a diversion tunnel reconstruction project,the influence of different height baffles on the hydraulic characteristics of the intersection section is studied through hydraulic model test.The results show that with the decrease of the height of the baffle,the pressure of the baffle increases,and the maximum pressure appears the upstream side.With the decrease of the height of the baffle,the flow in the diversion tunnel is smoother;The local head loss of the intersection section is reduced by 8.627%-15.063%;With decrease of the height of the baffle,the loss of the local head is smaller.It finds out that the baffle height fits relatively better in 1.05 times of the flow depth in design flux(shape d).The results can provide reference for the similar projects.