大型水电站分层取水叠梁门的脉动压力特性

Fluctuating Pressures Characteristics of Stoplogs Gate of Multi-Level Intake for Large Hydroelectric Station

为减少下泄低温水对下游生态环境的影响,某水电站进水口拟采取叠梁门分层取水方式.由于过流方式不同,叠梁门与普通平板闸门在荷载特性上存在明显差别.通过模型试验对进水口叠梁门的脉动压力进行测量,结合数值模拟结果,分析了叠梁门上脉动压力的分布规律及荷载特性.结果表明:在所有工况下,作用在叠梁门不同部位的脉动压力特性不同,但均在叠梁门下游侧底部出现了较大的脉动压力;叠梁门下游侧底部大漩涡产生的脉动压力是诱发叠梁门流激振动的主要激振力.提出了一种针对叠梁门顶部过流计算激振力的简易方法,可供工程设计参考使用.

Multi-level intake structure is applied by installing stoplogs gate in a certain hydroelectric station to reduce the effect of released cold water on downstream living creatures especially fish.Because of the different flow patterns,the load characteristics of stoplogs gate are significantly different from those of the ordinary plate gate.Through hydraulic model tests,the fluctuating pressures on the stoplogs gate were measured,and distribution law and characteristics of the fluctuating pressures were analyzed with the results of numerical simulation.The results show that the fluctuating pressures characteristics vary with the position on the stoplogs gate and larger fluctuating pressure appears on the bottom of the gate near the lower side under all conditions.The main excited power to induce flow-induced vibrations of gate is the fluctuating pressure on the gate in the bottom eddy area near the lower side.A simple way to compute the excited power was proposed for reference in engineering design.