相交轴转子系统当量化建模与扭振响应分析

齿轮联结的相交轴转子系统具有转子不同体、不同速、不同轴线等结构特点,使其动力学建模异于常规转子系统,论文采用当量化建模方法,将相交轴转子系统转化为同转速、同轴线的转子系统并建立动力学模型,通过与已有研究对比验证了文中基于DyRoBeS当量化建模方法的有效性.以相交轴齿轮联结转子系统典型结构——某型直升机尾传动系统为研究对象,建立了当量化转子系统动力学模型,分析了系统各阶扭振临界转速及其组成、联结齿轮啮合刚度对扭振的影响、联结齿轮转动惯量对系统临界转速的影响,结果表明:传动系统第1、2阶临界转速为派生临界转速,其余8阶均源于各组成轴;中、尾减啮合刚度值与扭振的各阶共振峰值存在映射关系,部分啮合刚度值会激发共振极大值,应尽量避免;中、尾减啮合刚度变化会引发系统临界转速的变化,尤其是第1、2阶临界转速;不同阶临界转速对各个联结齿轮转动惯量的敏感性亦不同.论文从转子动力学角度研究了齿轮联结的相交轴转子系统的动力学特性,可为此类转子系统的结构优化设计及运行维护提供理论依据.

Intersecting shaft rotor system idealized modeling and torsional vibration response analysis

Intersecting shaft gear-rotor system with the structure characteristics of multi-body, different speed and axis line, which make the rotor dynamics modeling method different from coaxial rotor system, the paper adopts a idealized method that can enable the rotor system with characteristics of multi-body, different speed and axis line change into the coaxial rotor system with the same speed , then the modeling method using idealize modeling method and Finite element software DyRoBes is verified by contrast researches. Use helicopter tail drive system a typical structure of intersecting shaft gear-rotor-system as the research object, establish its idealized rotor system dynamic model, then analyze the natural frequency, torsional mode, the influence of moment of inertia of the coupling gear on the natural frequency, finally the influence of the mesh stiffness are analyzed. The results show that in the first 10 orders of natural frequency of the transmission system, except the 1st and 2nd order are coupling natural frequency, the other orders are all derived from the natural frequency of each component shaft. There is a mapping relationship between the meshing stiffness values of middle and tail reduction, and some meshing stiffness values will stimulate the maximum torsional vibration value of resonance, which should be avoided. Meshing stiffness of the middle and tail will cause changes of critical speed, especially the 1st and 2nd critical speed. Different order natural frequency has different sensitivity to change of inertia of different components. This paper studies the dynamic characteristics of intersecting shaft gear rotor system from the view of rotor dynamics, which can provide theoretical basis for the optimal design of this kind of rotor system.