龙羊峡水电站表孔弧形闸门原型试验研究

Prototype test and research on arc steel gate in Longyangxia Hydropower Station

针对龙羊峡水电站表孔弧形闸门存在的振动和异常声响问题,通过闸门的制作安装精度检测、启闭力测试、模态测试、动力响应测试、声响测试等原型试验,对闸门振动原因和特性、启闭力不均衡问题、支臂的应力应变特性、异常声响的原因和特性等进行深入的研究。研究成果表明:①闸门在强振区的振动主要是变形模量小的水封的振动,水封振动的原因是闸门轨道存在严重偏差和铰轴同心度超标;②异常声响主要是两个铰轴同心度的偏差相对较大和铰轴与轴套之间存在干摩擦所致;③门体振动、支臂应力应变和启闭力的交替变化、铰轴异常声响之间都有密切关系,闸门在强振区的主要频率(1号门约4Hz;2号门约3Hz)基本一致。

Aimed at the problems of vibration and exceptional noise of arc-gate in Longyangxia Hydropower Station, the vibration causes and characteristics of the arc steel gate, the unbalance problems of forces in course of the gate's switch-on and switch-off, the characteristics of the arm′s stresses and strain, the causes and characteristics of the exceptional noise are analyzed deeply by means of the measured precision of gate erection, the measured forces in course of the gate's switch-on and switch-off, the tested model of gate, the tested dynamic responds, the measured exceptional noise. The following conclusions are obtained: I. strong vibration of arc steel gate roots in the vibration of water seal with low modulus of elasticity, the vibrant causes of water seal due to bigger erection error of gate orbit and degree of two articulation axes in line. II. Exceptional noise of arc steel gate roots in direct friction between articulation axes and articulation axes cover. III. vibration of gate, alternant change of arm stress, alternant change of force in course of the gate's switch-on and switch-off and exceptional noise, which have contact with each other, primary frequency of alternant change or exceptional noise in strong vibration area are consistent with primary frequency of vibration (the frequency of No.1 gate is 4Hz, the frequency of No.2 gate is 3Hz).