一种柔性支承转子系统的地震动响应分析

Seismic response analysis of an ultra-high speed rotor system with flexible supports

以工作在柔性支承上的超高速转子系统为对象,研究支撑框架对系统地震动响应的影响。采用欧进萍改进的地震波模型作为输入载荷,碰摩力模型模拟动静件之间的碰摩过程,以拉格朗日方法建立了系统的动力学模型。计算分析了支撑框架对地震动响应中时域波形、碰摩时间、最大振幅的影响。结果表明:转子系统和支撑框架地震动响应呈现出一致的规律,转子振幅约是支撑框架的1.5倍;最大振幅和碰摩时间随支撑框架刚度单调增长、随质量单调减小、随阻尼单调减小;支撑框架基频是影响转子系统地震动响应的关键因素;在工程设计中应先从保持基频不变的思路出发,如果支撑框架质量增加不可避免,而刚度又增无可增,则可增加支撑框架上的阻尼。

Here,taking an ultra-high speed rotor system with flexible supports as the study object,effects of support frame on seismic response of the system were studied.Using the seismic wave model improved by OU Jinping as input load and the rubbing force model to simulate the rubbing process between moving and stationary parts,the dynamic model of the system was established with Lagrange method.Effects of support frame on time domain waveform,rubbing time and maximum amplitude of the system’s seismic response were calculated and analyzed.The results showed that seismic responses of the rotor system and support frame are consistent,and rotor amplitude is about 1.5 times that of support frame;the system’s maximum amplitude and rubbing time increase monotonically with increase in support frame stiffness,decrease monotonically with increase in its mass,and decrease monotonically with increase in its damping;the fundamental frequency of support frame is the key factor affecting the system’s seismic response;in engineering design,designers start from the idea of keeping support frame fundamental frequency unchanged,if increase in support frame mass is inevitable while its stiffness can’t increase,support frame damping can be increased.