为改善航空发动机中央传动杆的动态特性，结合某航空发动机中央传动杆的结构及工况参数，采用有限单元法建立动力学模型及方程，对中央传动杆的动态特性进行理论分析．探讨陀螺力矩对临界转速以及中间辅助支点的支承位置和支承刚度对中央传动杆临界转速的影响．提出中间辅助支点最佳位置的确定方法，对中央传动杆的工程设计具有一定的应用价值．分析结果表明：在工作转速范围内，陀螺力矩对其固有频率的影响较小，不大于0．5％；中间辅助支点设置在中间无支点时的二弯“振型节点”处时，可使中央传动杆获得最高的临界转速，以及最大的支承刚度设计裕度．试验结果验证了理论计算方法的正确性．%To improve the dynamic performance of a radial driving shaft employed on an aero engine, a theoretical analysis based on FEM is conducted. Dynamic model and equation is constructed consistent with the actual structure and practical operating condition. The influences of gyroscopic moment, supporting stiffness and location of the intermediate fulcrum on shaft critical speed are discussed. The method to determine the intermediate supporting location is suggested, which is believed to be valuable in practical design of radial driving shaft. Analysis results indicate that the gyroscopic moment has minimum impact on the natural frequency, less than 0. 5%. When the intermediate fulcrum is located at the point of the ‘Natural Mode ’ of second curved modal shape with no intermediate fulcrum, the highest critical speed and design margin of supporting stiffness could be achieved. The experimental results prove the correct of the theoretical analysis.
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