多轴齿式离心压缩机转子系统耦合振动特性分析

Analysis of Coupling Vibration Characteristics of the Rotor Systems for Integrally Geared Centrifugal Compressors

以某五平行轴齿式离心压缩机为研究对象,建立多平行轴齿轮耦合转子系统有限元模型。采用数值方法,在考虑齿轮耦合与不考虑齿轮耦合两种情况下分别对系统运动方程进行求解,得到系统横向及轴向振动的固有频率和振型,在考虑陀螺力矩的情况下计算系统临界转速值并绘制Campbell图,进而详细分析齿轮啮合作用对多平行轴转子系统动力学特性的影响。研究表明齿轮的耦合作用会使系统派生出新的固有频率及耦合振型,整体系统表现为原有单轴的固有特性与耦合特性两种模式,系统出现新的临界转速值,同时分别指出齿轮耦合作用对系统横向振动和轴向振动的不同影响以及派生频率的来源。

Taking a centrifugal compressor of gear type with five parallel shafts as the research object, the finite element model of a multi-parallel-shaft rotor system was established. The natural frequencies, lateral vibration modes and longitudinal vibration modes were acquired in numerical simulation considering the two conditions of gear coupling and uncoupling respectively. The critical speed was calculated and the Campbell diagram was drawn with the gyroscopic moment considered. The impact of gear meshing on the dynamic performance of the rotor system was analyzed. The result shows that the coupling effect of gears can yield new intrinsic frequencies and coupled modals for the system, the system demonstrates the original single-shaft intrinsic characteristic and coupling characteristic, and new critical speeds appear due to the gear meshing. Finally, the influence of the gear meshing effect on the radial vibration and the transverse vibration of the rotor system and the cause of the new intrinsic frequencies were analyzed.