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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Finite element analysis of fluttering plates reinforced by flexible beams: An energy-based approach

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Autor(es):
Pacheco, Douglas R. Q. [1] ; Marques, Flavio D. [1] ; Ferreira, Antonio J. M. [2]
Número total de Autores: 3
Afiliação do(s) autor(es):
[1] Univ Sao Paulo, Sao Carlos Sch Engn, Sao Carlos, SP - Brazil
[2] Univ Porto, Fac Engn, Porto - Portugal
Número total de Afiliações: 2
Tipo de documento: Artigo Científico
Fonte: Journal of Sound and Vibration; v. 435, p. 135-148, NOV 24 2018.
Citações Web of Science: 6
Resumo

Aircraft and spacecraft skin can undergo potentially destructive aeroelastic motions in high-speed flight. Reliable mathematical modelling is crucial for understanding such phenomena and aiding aerospace structural design. The panels of real skin structures are normally thin-walled elements riveted to beams and frames that act as stiffeners. In panel flutter literature, however, such stiffening components are normally idealised as perfectly immovable supports or, at best, as linear springs, which restricts the level of information to be obtained from the analyses. Aiming to better understand how the flexibility and mobility of stiffeners affect the aeroelastic behaviour of reinforced panels, the present work employs a more realistic model for skin structures. The Mindlin theory is used for the panel, and the stiffener is modelled as an eccentric Timoshenko beam. Geometrical non-linearity is added to both models, and the supersonic aerodynamic loads are calculated via linear piston theory. The Finite Element Method is employed for spatial discretisation, and an iterative Newmark-type scheme is used for time marching. Differently from what is typically done in the literature, the results are discussed not only from the standpoint of oscillation amplitudes, but also using energy distribution assessment. Solutions have been generated for several flow conditions and stiffener cross-sections. Comparison between the present results and those from a structurally-idealised model has demonstrated that modelling stiffeners as immovable boundaries overestimates flutter onset conditions and underestimates post-flutter amplitudes, thus being an unconservative simplification. Energy distribution analysis has shown that, for reasonably flexible stiffeners, the aeroelastic system can bifurcate and move between two stable limit cycles, one of which displays larger energy levels. Furthermore, it has been shown that the total energy can be unevenly distributed along the structure during flutter, which can be used to determine suitable locations for control devices or energy sinks. (C) 2018 Elsevier Ltd. All rights reserved. (AU)

Processo FAPESP: 17/26284-6 - Modelagem aeroelástica não linear de painéis aeronáuticos reforçados, pelo método dos elementos finitos
Beneficiário:Douglas Ramalho Queiroz Pacheco
Modalidade de apoio: Bolsas no Brasil - Mestrado