水轮发电机组在运行过程中由于水力、机械、电磁等原因不可避免会发生振动,机墩作为水轮发电机组的支承结构,其结构的稳定性至关重要.建立起机墩、蜗壳、尾水管直至地基的整体模型,通过数值模拟可以得到机墩在谐振荷载作用下任意部位的幅值,在此基础上运用统计学方法响应曲面试验方法,以机墩内径、厚度两个参数作为设计变量,结合信息量权数法将机墩在垂向、径向、环向的最大振幅用一个综合目标函数来代替,并以该综合目标函数作为优化目标,由此建立起响应曲面模型,并对机墩模型进行优化.结果表明:优化后的机墩垂直方向的最大振幅减少了17.8%,环向最大振幅减少了4.7%,径向最大振幅减少了1.4%;本工程机墩的内径建议取值范围为1.73D1~1.83D1,机墩厚度的建议取值范围为0.50D1~0.63D1;响应曲面的优化设计方法可以有效应用于水电站机墩的减振设计中.
Due to hydraulic,mechanical,electromagnetic and other reasons,vibration will inevitably occur during the operation of the hydro-electric generating set.As the supporting structure of the hydroelectric generating set,the stability of the pier is very important.In this pa-per,the whole model of the pier,volute,draft tube and foundation is established.The amplitude of any part of the pier under the resonant load can be obtained by numerical simulation.On this basis,the response surface method is used by statistical method.The two parameters of the inner diameter and thickness of the pier are taken as the design variables,and the information weight method is used to replace the maxi-mum amplitude of the pier in the vertical,radial and circumferential directions with a comprehensive objective function,and the comprehen-sive objective function is used as the optimization objective.The response surface model is established and the pier model is optimized.The results show that the maximum amplitude of the optimized pier in the vertical direction is reduced by 17.8%,the maximum amplitude in the circumferential direction is reduced by 4.7%,and the maximum amplitude in the radial direction is reduced by 1.4%.The recommended value range of the inner diameter of the pier is 1.73D1~1.83D1,and the recommended value range of the pier thickness is 0.50D1~0.63D1.The optimization design method of response surface can be effectively applied to the vibration reduction design of hydropower station pier.