敏感度法估算转子危险转速区

Sensitivity Method for Estimating Dangerous Speed for Rotors

关键词:  转子  临界转速  传递系数法  多层叠片阻尼器  振动  动力学 

Key words:  Rotor  Critical speed  Transfer coefficient method  Multilayer laminated damper  Vibration  Dynamics

摘要:

提供一种估算含多层叠片阻尼器转子危险转速区的“敏感度”分析法。采用传递系数法,计算刚度区间各离散点对应的临界转速,通过分析临界转速相对支承刚度变化的敏感程度,确定转子危险转速区。首先,划分转子计算节点,计算各节点物性参数值；其次,取定支承刚度存在的范围,按二分法离散刚度区间,利用传递系数法,循环计算每个离散刚度点对应的临界转速和振型,直到找出振型突变的两个相邻刚度点；接着,做出临界转速随刚度变化的规律曲线,根据曲线找出临界转速变化剧烈时对应的子刚度区间,该区间与上步找出的刚度点行成的区间应是相符的；然后,若希望得到更高精度的结果,可以在子刚度区间内,重复步骤二,直到得到满意结果。该方法易于实现模块化操作,避免在敏感支承刚度区出现危险转速。 

Abstract:

A sensitivity method to estimate the dangerous speed for rotors with multilayer laminated damper was provided. The method, which uses the transfer coefficient method to compute critical speed for every scattered stiffness point in preset stiffness domain, tends to verify the dangerous speed of a rotor through analyzing the sensitivity of critical speed changing with supporting stiffness. The first step is to partition the rotor into many stations, and to compute their physical characteristics. The second step is to set the domain of supporting stiffness and scatter stiffness points inside by dichotomy method, then to circularly compute the critical speed and modes corresponding to every scattered stiffness point until the two neighboring stiffness points with the phenomenon of modes changing extremely are found.The third step is to draw the law curve which shows how the critical speeds change with supporting stiffness and find the sub-domain corresponding to the phenomenon of the critical speed changing extremely. The sub-domain should be consonant with that, which is formed by those two neighboring points found in the former step. Then, if more accurate result is expected, in the sub-domain, repeat the second step until find the satisfying critical speed. It is convenient to modularize this method and helpful to avoid dangerous speed in sensitive support stiffness domain. 