不同折叠角下含间隙折叠机翼极限环振荡分析  

Analysis of the Limit Cycle Oscillations of the Folding Wing with Clearance at Different Folding Angles

作　　者：杨执钧 张忠[1] 高博[1] 郭静[1] 魏龙 YANG Zhijun;ZHANG Zhong;GAO Bo;GUO Jing;WEI Long(Science and Technology on Reliability and Environmental Engineering Laboratory,Beijing Institute of Structure and Environment Engineering,Beijing 100076,China)

机构地区：[1]北京强度环境研究所可靠性与环境工程技术重点实验室,北京100076

出　　处：《强度与环境》2024年第3期37-45,共9页Structure & Environment Engineering

基　　金：国家自然科学基金(51805036);重点实验室基金(6142004220106)。

摘　　要：折叠机翼作为变体飞行器的重要变体机构之一,其气动弹性响应规律研究为变体飞行器稳定性及操纵性的提升奠定基础。本文提出基于干风洞的含间隙折叠机翼地面颤振虚拟试验模型建模方法,其中折叠机翼翼面子结构采用Craig-Bampton方法建立其刚柔耦合降阶模型,子结构连接采用线性/非线性弹簧连接,气动力采用偶极子格网法获得并转化为激振器集中力,由于地面颤振试验中气动力建模需基于统一的模态振型,针对含间隙折叠机翼采用虚拟质量法获得统一坐标下的虚拟模态振型。仿真结果表明,基于Craig-Bampton方法建立的线性折叠机翼地面颤振虚拟试验模型预测颤振速度与商用软件相比误差低于2%。当模型中采用非线性弹簧连接时,折叠机翼在低于和高于线性颤振速度下均会形成极限环振荡,仿真表明由于间隙非线性的影响,极限环的临界速度比线性颤振降低。研究发现折叠角0°下间隙大小对极限环幅值具有显著影响,而折叠角30°下间隙大小则对极限环幅值几乎不产生影响。As one of the important variant mechanisms of the variant aircraft,the aeroelastic response law of the folding wing is studied to lay the foundation for the improvement of the stability and maneuverability of the variant aircrafts.In this paper,a modeling method for the virtual ground flutter test of folding wings with clearance based on dry wind tunnel is proposed.The Craig-Bampton method is used for the substructure of the folding wing surface to establish its rigid-flexible coupling reduced-order model.The linear/nonlinear spring is used for the connection of the substructure.The aerodynamic force model is computed via the double lattice method and converted into concentrated force trough the exciter.Due to only unified mode shape can be used for establishing the aerodynamic model in the ground flutter test,the virtual mass method is used for the folding wings with the clearance nonlinearity as a unified coordinate to represent virtual mode shapes.The simulation results show that the flutter velocity error of the virtual ground flutter test model of folding wings based on the Craig-Bampton method predicts is less than 2%.When nonlinear spring connections are used in the model,the folding wing will form limit cycle oscillations below and above linear flutter velocities.Due to the influence of clearance nonlinearity,the critical velocity of the limit cycle oscillations is lower than that of linear flutter.It is found that the size of clearance in the 0°folding angle model has a significant effect on the amplitude of the limit cycle oscillations,while the size of clearance in the 30°folding angle model has almost no effect on the amplitude of the limit cycle oscillations.

关 键 词：折叠机翼 柔性多体动力学 间隙非线性 颤振 极限环 

分 类 号：V211.47[航空宇航科学与技术—航空宇航推进理论与工程]