组合转子动力学集中参数模型建模研究
Research on Dynamic Lumped Parameter Modeling of Combined Rotor

组合转子作为燃气轮机的核心部件，结构特殊，受力情况复杂，目前其动力学特性研究基本依赖于有限元模型，难以对其深层机理进行系统研究。从难度较大的弯曲振动入手，建立了组合转子的铁木辛柯梁（Timoshenko beam）集中参数模型。根据组合转子非连续性的结构特点，将组合转子以轮盘为单元进行集中参数化，建立弯振解析模型；利用MATLAB对该集中参数模型进行固有频率、振型计算以及谐响应分析，将其计算结果与有限元模型结果进行对比。结果表明：该集中参数模型能较为准确地反映出组合转子的固有特性，可以适用于组合转子的动力学分析与研究。相比于有限元模型，该模型能更为直观地反映组合转子的内部机理，并且将计算机运算时间缩短了3个数量级以上。
As the core component of gas turbine, the structure of combined rotor is relatively special and its force condition is complex. At present, the study on its dynamic characteristics is fundamentally based on finite element mode. Therefore, to conduct systematic study on its deep mechanism is difficult. In this paper, the Timoshenko beam lumped parameter model of combined rotor was developed. According to the discontinuity of combined rotor, which is one of the structural features, the combined rotor was central parameterized using the disk as the unit, and the bending vibration mode was modeled. Then, MATLAB was used to calculate the natural frequency and mode of vibration of the centrally parametric model, and analyze harmonic response; the results were contrastively analyzed with the results of finite element model. The results show that the natural frequency the combined rotor can be accurately reflected by the centrally parametric model and it can be used to study and analyze the dynamics of combined rotor. Compared to finite element model, the internal mechanism of the combined rotor was reflected by this centrally parametric model more accurately and the calculation time was shortened over three orders of magnitude