摘要
目的 基于大展弦比无人机的几何大变形的特性开展颤振分析。方法 基于大展弦比无人机大变形状态下的非线性动力学特性,得到非线性平衡态下的结构刚度,通过与非定常气动力的耦合,得到大展弦比无人机的非线性颤振特性。在此基础上,探究考虑曲面效应的平板气动力与结构非线性动力学耦合下的大展弦比无人机的颤振特性。结果 考虑几何非线性条件下的颤振速度相较于线性颤振速度下降约8%,考虑曲面效应的颤振速度相较于平板气动力下的颤振速度下降约11%。结论 结构大变形引起的几何非线性会引起机翼水平和垂直的运动耦合,改变相应的频率和振型,从而影响气动弹性耦合关系,降低临界颤振速度。另外,考虑曲面效应的气动力模型会改变与结构模型的插值关系,引起颤振临界速度的降低。
The work aims to conduct flutter analysisbased on the geometric deformation characteristics of high aspect ratio unmanned aerial vehicles.Based on the nonlinear dynamic characteristics of high aspect ratio unmanned aerial vehicles in large deformation states,the structural stiffness in nonlinear equilibrium states was obtained.The nonlinear flutter characteristics of high aspect ratio unmanned aerial vehicles were obtained by coupling with unsteady aerodynamics.On this basis,the flutter characteristics of high aspect ratio unmanned aerial vehicles under the coupling of flat plate aerodynamics and structural nonlin-ear dynamics considering surface effects were explored.Considering geometric nonlinearity,the flutter velocity decreased by about 8%compared with linear flutter velocity.Andconsidering surface effects,the flutter velocity decreased by about 11%compared with flat aerodynamic forces.The calculation results indicate that the geometric nonlinearity caused by large structural deformation can cause coupling of horizontal and vertical wing motion,change the corresponding frequency and vibration mode,thereby affecting the aeroelastic coupling relationship and reducing the critical flutter velocity.Moreover,aerodynamic models that consider surface effects can alter the interpolation relationship with structural models,leading to a decrease in the critical flutter velocity.
作者
李广耀
卢佳
胡炜
徐焱
LI Guangyao;LU Jia;HU Wei;XU Yan(AVIC Chengdu Aircraft Industrial(Group)Co.,Ltd.,Chengdu 610092,China)
出处
《装备环境工程》
CAS
2024年第9期100-105,共6页
Equipment Environmental Engineering
关键词
颤振
几何非线性
大展弦比
无人机
曲面效应
气动力
flutter
geometric nonlinearity
high aspect ratio
unmanned aerial vehicles
surface effect
aerodynamics
