CAJ | 학술논문

大柔性太阳能无人机在气动载荷的作用下产生较大的弯曲变形，机翼结构的刚度、质量分布等特性亦发生较大改变，线性理论无法满足这类飞机气动弹性稳定性分析的精度要求。基于Cor-ota -tional（CR ）理论，推导了结构变形后的切线刚度矩阵和质量矩阵，建立了大柔性机翼结构动力学模型；采用建立在局部气流坐标系下的片条非定常气动力模型，建立了考虑几何非线性效应的大柔性无人机气动弹性运动方程。引入准模态假设，采用P-k法研究了几何大变形对类＂太阳神＂布局太阳能无人机的气动弹性稳定性的影响。研究结果表明：随着弯曲变形的增加，非线性颤振速度可降低10％以上，非线性颤振频率可下降8％；合理的增加扭转刚度、前移弹性轴、前移剖面质心等，均可以有效改善几何大变形引起的不利影响。研究工作对大柔性飞机的气动弹性设计具有一定的参考意义。
대유성태양능무인궤재기동재하적작용하산생교대적만곡변형，궤익결구적강도、질량분포등특성역발생교대개변，선성이론무법만족저류비궤기동탄성은정성분석적정도요구。기우Cor-ota -tional（CR ）이론，추도료결구변형후적절선강도구진화질량구진，건립료대유성궤익결구동역학모형；채용건립재국부기류좌표계하적편조비정상기동력모형，건립료고필궤하비선성효응적대유성무인궤기동탄성운동방정。인입준모태가설，채용P-k법연구료궤하대변형대류＂태양신＂포국태양능무인궤적기동탄성은정성적영향。연구결과표명：수착만곡변형적증가，비선성전진속도가강저10％이상，비선성전진빈솔가하강8％；합리적증가뉴전강도、전이탄성축、전이부면질심등，균가이유효개선궤하대변형인기적불리영향。연구공작대대유성비궤적기동탄성설계구유일정적삼고의의。
A very flexible solar powered UAV under aerodynamic loading undergoes large deformation, thus chan-ging the stiffness characteristics and mass distribution of its wing structure.It is impossible to obtain its precise aero-elastic stability with the linear theory.Therefore we use the co-rotational theory to develop the aeroelastic stability a-nalysis algorithm suitable to a very flexible aircraft, derive the expression of tangent stiffness matrix and mass matrix of a spatial two-node beam element, and establish the dynamic model of a geometrically nonlinear structure.Using the unsteady aerodynamic strip model and the quasi-mode assumption, we derive the aeroelastic motion equations. We use the P-K method to analyze the aeroelastic stability characteristics of a solar-powered UAV with the layout similar to Helios under geometrically large deformation.The analysis results on a test are compared with other analy-sis results given in Table 2, and they show good agreement:as the wing deformation increases, the nonlinear flutter speed decreases by 10%, and the nonlinear flutter frequency decreases by 8%;the aeroelastic stabilities of a solar-powered UAV will be improved by increasing torsional rigidity or by moving its elastic axis and the mass center of its wing section toward the leading edge.