热致轴向窜动引发的双盘转子扭转振动分析

FLEXURAL-TORSIONAL VIBRATION ANALYSIS OF A DOUBLE-DISK ROTOR CAUSED BY THERMAL EXPANSION INDUCED AXIAL MOVEMENT

以航空发动机整机系统的结构特点及复杂的运行环境为研究背景,运用Lagrange方法建立双盘转子在不平衡激励和轴向窜动影响下的弯扭耦合动力学模型;针对温度非均匀分布以及热膨胀性质引起的转轴轴向窜动,导出转/静盘面接触时环带面摩擦力与摩擦力矩表达式;最后采用4阶Runge-Kutta方法对系统进行数值求解.对系统进行动力学分析的结果表明,对于非对称双盘转子结构,热膨胀所积蓄的温度内力引发的转子轴向窜动将改变转子系统的固有特性,所产生转静件盘面环带面摩擦力与力矩,是造成转轴扭转振动的关键因素之一.

Taking the structural characteristics and the complexity operating environment of the whole aero-engine system as the research background,the Lagrange approach was employed to establish the flexural-torsional dynamic model for a double-disk rotor subjected to the influence of imbalance exciting force and axial movement caused by the thermal expansion.Due to the axial movement of the shaft caused by the non-uniform distribution of temperature and thermal expansion properties,the analytical expressions of the surface rubbing force and moment were derived respectively.Finally the fourth-order Runge-Kutta method was adopted to solve the dynamic model.Numerical analysis on the dynamical response of the system shows that the temperature stress accumulated by thermal expansion,axial movement of the shaft,and surface rubbing moment,are all the key factors,which would change the inherent physical properties and cause flexural-torsional vibration of the double-disk rotor.