摘要
颤振边界与颤振耦合机理对飞行器设计与颤振试验设计有着重要意义。模态坐标下的颤振计算通过各阶广义坐标的变化特性来确定颤振边界,并对颤振耦合机理进行分析。然而这常常依赖设计人员的工程经验,难以保证判别标准量化统一。基于功能原理提出了一种新的颤振模态参与度分析方法,通过广义坐标下广义气动力做功的能量累积,实现颤振模态参与度分析。分别采用频域方法与CFD/CSD方法对AGARD445.6标模进行颤振计算,验证了所提模态参与度分析方法的正确性。随后针对双体飞机颤振计算中发现的"漂移频率"现象,使用所提方法进行了解释,凸显了方法的优势。综合表明,所提模态参与度分析方法较好地反映了颤振耦合机理,具有指标正确可靠、结果归一化强、物理意义明确、适用于复杂结构复杂模态的特点。
Flutter boundaries and flutter coupling mechanisms are of high significance for aircraft design and flutter tests.The flutter boundary is determined by the distinguishing characteristic of the generalized coordinate of modes,which often depends on the experience of designers and therefore it is difficult to guarantee the quantitative uniformity of discriminant standards.This paper proposes a new method for the flutter mode indicator analysis based on the principle of work and power.The analysis is realized through energy accumulation of generalized force work on modal coordinates.Rational function approximation and the CFD/CSD method are used respectively in the AGARD445.6 flutter mode indicator analysis to verify the proposed method.Then,the‘frequency drifting’phenomenon of twin-fuselage aircraft is explained logically by the proposed method,highlighting the advantage of the proposed method.The results show that the proposed method well reflects the flutter coupling mechanism,exhibiting characteristics of reliable flutter modes indexes,clear physical meaning and strong results normalization.
作者
王昕江
刘子强
郭力
付志超
吕计男
WANG Xinjiang;LIU Ziqiang;GUO Li;FU Zhichao;LYU Jinan(China Academy of Aerospace Aerodynamics,Beijing 100074,China;China Academy of Launch Vehicle Technology,Beijing 100076,China)
出处
《航空学报》
EI
CAS
CSCD
北大核心
2022年第1期408-418,共11页
Acta Aeronautica et Astronautica Sinica
关键词
颤振
气动弹性
功能原理
模态参与度
漂移频率
flutter
aeroelasticity
principle of work and power
mode indicator
frequency drift
