基于实体单元的转子动力特性计算方法

Rotor dynamic analysis based on solid element

现代航空发动机振动分析必须考虑各结构间的动力影响,因此,应该运用实体单元对发动机进行整机建模.为了在进行复杂转子系统动力特性分析时能够考虑陀螺力矩的影响,在对八节点六面体实体单元有限元动力方程推导的基础上,对通用有限元软件MSC/NASTRAN,利用DMAP语言进行二次开发,通过修改解题序列,加入陀螺力矩、科氏力和离心力的影响因素.在对典型结构计算分析的基础上,总结了转动结构振动的一些特点,通过对计算结果的对比,证明本程序在计算复杂旋转结构模型时能全面考虑壳体行波振动和转子进动的影响,指出了其在整机建模中的应用前景.

In modem times, dynamical interaction of different structures should be taken into account in aero - engine vibration analysis, as a reason, the engine should be modeled by solid elements. To take the gyroscopic effect into account in the analysis of complex rotor dynamics characteristic, based on the dynamics finite element equation of 8 node element CHEXA, a rotor dynamic the platform of MSC/NASTRAN with the DMAP process by analysis software package was developed on adding gyroscopic torque , Coriolis acceleration and centrifugal force to it. Dynamic analysis of typical models were performed, including a diagonal compressor and a conical shell. The results of calculation and experiments were compared. Typical vibration characteristics as rotor bending, shells traveling waves and various sectional vibrations were summered. The results showed that traveling waves and rotor precessions could be taken into account accurately while using the author g method. For the vibration of complex rotors can be calculated with the method, the foreground of the use in full modeling in multi-field was figured out.