Modeling and identification of freeplay nonlinearity

Autor(es)

Abdelkefi, A. ^[1] ; Vasconcellos, R. ^[2] ; Marques, F. D. ^[2] ; Hajj, M. R. ^[1]

Afiliação do(s) autor(es)

^[1] Virginia Polytech Inst & State Univ, Dept Engn Sci & Mech, Blacksburg, VA 24061 - USA

^[2] Univ Sao Paulo, Lab Aeroelast, Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Sound and Vibration; v. 331, n. 8, p. 1898-1907, APR 9 2012.
• Citações Web of Science: 26

Resumo

A nonlinear analysis is performed for the purpose of identification of the pitch freeplay nonlinearity and its effect on the type of bifurcation of a two degree-of-freedom aeroelastic system. The databases for the identification are generated from experimental investigations of a pitch-plunge rigid airfoil supported by a nonlinear torsional spring. Experimental data and linear analysis are performed to validate the parameters of the linearized equations. Based on the periodic responses of the experimental data which included the flutter frequency and its third harmonics, the freeplay nonlinearity is approximated by a polynomial expansion up to the third order. This representation allows us to use the normal form of the Hopf bifurcation to characterize the type of instability. Based on numerical integrations, the coefficients of the polynomial expansion representing the freeplay nonlinearity are identified. Published by Elsevier Ltd. (AU)

• Processo FAPESP: 07/08459-1 - Análise de séries temporais aeroelásticas não lineares: um estudo experimental
• Beneficiário: Rui Marcos Grombone de Vasconcellos
• Modalidade de apoio: Bolsas no Brasil - Doutorado