| Flutter will reduce the fatigue life of the structure,and even lead to structural instability and disintegration in a very short time,which brings great hidden trouble to the safety of aircraft.In order to avoid the damage caused by flutter on the aircraft panel structure,designers pay attention to the application of new materials,the improvement of the structure form and the consideration of structural damage in the flutter analysis of the panel structure.In this thesis,three flutter problems of composite panels in supersonic flow field are studied.Firstly,based on the mixed rule model,five distribution forms of carbon nanotubes are considered,and the time-domain flutter characteristics of carbon nanotubes reinforced composite panels are investigated.Secondly,reinforcing strips are installed on the surface of carbon nanotube reinforced composite panels to improve the structural form of the panels.The time-domain flutter characteristics of the reinforced strip panel structure are studied.Finally,considering the possible damage,anisotropic damage model is introduced to study the time-domain flutter characteristics of damaged panels.In the research process,the structural model is based on Mindlin plate theory and Von-Karman large deformation theory.In terms of aerodynamic model,the first order quasi-steady piston aerodynamic theory is adopted.Then,based on Hamilton’s principle and finite element method,the finite element flutter motion equation of composite panel is established.Newmark method and Newton method are used to iteratively solve the nonlinear response characteristics of panel in time domain,such as critical flutter pressure and limit cycle.The correctness of the calculated results is verified by comparing with the literature results,and the influence of key parameters on the time-domain flutter characteristics of the composite panels is analyzed. |
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