机动飞行环境下双转子系统主共振特性分析

Analysis of primary resonance characteristics of dual-rotor system in maneuvering flight environment

以双转子系统为研究对象,综合考虑高低压转子双频不平衡激励、中介轴承间隙以及机动载荷,通过Lagrange方程,建立了水平盘旋机动飞行环境下双转子系统动力学模型,研究了双转子系统的主共振特性,分析了水平盘旋机动载荷对双转子系统主共振特性的影响规律,探讨了机动飞行环境下中介轴承间隙对双转子系统主共振特性的影响规律。研究结果表明,双转子系统存在振动突跳和双稳态等典型的非线性动力学行为,水平盘旋机动载荷增大会对双转子系统产生"刚度增强效应",中介轴承间隙增大会对双转子系统产生"刚度弱化效应"。

This paper focuses on the primary resonance analysis of a dual-rotor system considering the two rotor imbalanced excitations with different rotating speeds,the radial clearance of the inter-shaft bearing and the maneuver load.The vibration equations of the dual-rotor in the hover flight environment are formulated using the Lagrange equation.The primary resonance responses are then obtained by numerical methods,followed by the investigation into the primary resonance characteristics under the influence of the maneuver load and the clearance of inter-shaft bearing.The results reveal that the dual-rotor system has some typical nonlinear dynamic behaviors,such as vibration jump and bi-stable phenomenon.The maneuver load exerts a"stiffness enhancement effect"while the inter-shaft bearing clearance a"stiffness weakening effect"on the dual rotor system.