基于ARMD和流固耦合的考虑地震载荷的水电机组转动部件强度分析

Strength analysis of rotational parts of hydroelectric unit under seismic loads based on ARMD and FSI

为更准确、全面地分析水电机组转动部件强度问题,本文基于CFD性能预测方法,对水轮机内部流场进行三维数值模拟,并采用单向流固耦合方法将流场的计算结果作为初始条件加载到结构场,对各部件进行静载和地震载荷下的仿真计算。其中对于结构复杂、刚度阻尼值随运动变化明显的导轴承,采用转子动力学程序ARMD(Advanced Rotating Machinery Dynamics)模拟计算其动力特性系数。研究结果表明:文章采用方法能正确评估水轮机结构强度,对机组灾后运行可靠性分析有一定指导作用。

For more accurate and comprehensive analysis of the strength of rotating parts of a hydroelectric unit, first we numerically simulated the three-dimensional flow field in the hydraulic turbine using a CFD code. Then, with the calculation results used as initial conditions, simulations of fluid-structure interaction （FSI） were made to calculate the strength of each part under static loads and seismic loads separately. To calculate the dynamic coefficient of guide bearings, which have complicated structures with stiffness and damping factor varying significantly with the movement, a code of advanced rotating machinery dynamics （ARMD） was adopted. The results show that the method presented in this paper gives an accurate evaluation on the structural strength of a turbine and thus it is useful for the operation reliability analysis of those hydroelectric units that experienced earthquake disasters.