非线性空气舵系统模态试验及颤振设计研究

Modal Test and Flutter Research for Nonlinear Air Rudder System

在飞行器空气舵结构系统的设计中不可避免会存在摩擦、间隙、阻尼等非线性因素,在模态试验中表现为舵系统的模态试验结果随着激振力、舵面负载的变化产生明显的变化,而模态数据作为颤振设计的重要结构参数,对颤振分析结果有重大影响。工程设计中采用何种工况下的模态数据来进行颤振分析没有定论,保守设计认为所有模态状态下均不发生颤振则舵系统设计满足要求。以某空气舵系统为研究对象,给出了舵系统的模态变化范围,以不同工况下的模态数据为输入进行了颤振分析,最后采用当前的颤振设计思路,给出了在弯、扭频率最接近的模态状态下的颤振动压。

During the design of the air rudder system,nonlinear factors such as friction and clearance cannot be obviated.As a result,in the modal test the mode of the rudder system may differ with the amplitude of exciting force and load.Modal parameters are the principle inputs for flutter analysis,then these nonlinear factors impact the result of the flutter analysis.Which modal parameter should be used in the flutter analysis is not ascertained in the engineer designing;to achieve a conservative designing all the modal parameters are considered.An air rudder system is researched.The changing range of the modal parameters is determined.Flutter analysis for different modal parameters are achieved.In the end the flutter dynamic pressure of the rudder is present,on the condition that its bending frequency and torsion frequency are neared most.