操纵面非线性气动弹性响应引起的结构疲劳损伤分析方法研究

摘要

Due to free play,aeroelastic response of a control surface is nonlinear,limited cycle vibration (LCO) occurs on the control surface.Frequencies of LCO are higher than those of fatigue load spectrum of a plane structure,the total vibration cycle number of the control surface with in a plane's lifetime will be more than one hundred thousand times, and the fatigue damage of the control surface induced by LCO has to be taken into account.Thus the relationship between the aeroelastic data of the control surface (free play and velocity)and structural fatigue damage should be established. Here,based on the nonlinear aeroelastic analysis and the structural fatigue analysis,an analysis procedure was developed to study the relationship between LCO of the control surface and structural fatigue damage,and this analysis procedure could guide the setting of free play.In order to illustrate this method,the rotational angle responses of a control surface were obtained with the nonlinear aeroelastic analysis.Based on these responses,the fatigue load spectrum was gained. Finally,the structural fatigue analysis was performed to obtain the relationship between the fatigue damage features of the periphery structures and the nonlinear aeroelastic response of a control surface.%由于间隙的存在，随着速度的增加操纵面会发生非线性气动弹性响应，即操纵面发生极限环振动，其振动频率比飞机结构疲劳载荷谱的频率高，因此操纵面在每次飞行中只需经历1～2 s 的极限环振动，其在整个飞机服役期内累加得到的总循环数将达到10万次的量级，可见操纵面极限环振动引起的结构疲劳损伤不容忽视，所以需要建立起操纵面气动弹性数据（飞行速度和间隙）与结构疲劳损伤的对应关系。针对此问题，将非线性气动弹性分析方法和结构疲劳预测技术结合，发展一套分析流程用来讨论操纵面极限环振动与周边结构疲劳的关系，为设定操纵面间隙值提供参考。为了对此分析流程进行说明，对具有操纵面的复杂机翼进行了非线性气动弹性分析获得其偏转角响应，并将其转化为作用在作动器两头耳片上的疲劳载荷谱，通过疲劳分析获得周边结构疲劳特性与操纵面非线性气动弹性响应的关系。