Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
Study of a nonlinear aeroelastic model with combined SMA-based structural hysteresis and dynamic stall
Submission Author:
Vagner Candido de Sousa , SP
Co-Authors:
Lucas Victorelli Caravita, Luís Felipe Moreira da Silva Cassales, Giovanne Sooma Assunção Silva, Vagner Candido de Sousa
Presenter: Vagner Candido de Sousa
doi://10.26678/ABCM.COBEM2023.COB2023-0054
Abstract
This study focus on the aeroelastic behavior of a pitch-and-plunge airfoil undergoing nonlinear oscillations related to shape-memory alloy hysteresis and dynamic stall. The shape-memory alloy behavior is modeled based on the well-known Brinson's model. The unsteady aerodynamic loading is represented by the nonlinear Beddoes-Leishman model. Numerical results are comparable when linear (oversimplified by neglecting nonlinear contributions) and nonlinear (complete model) aerodynamic representations are considered in cases specifically at the flutter boundary of the airfoil and for relatively small initial disturbances. With increasing airflow speeds the amplitudes of oscillation grow over time and the linear aerodynamic model overestimates the amplitudes more severely. For the same conditions, the nonlinear model predicts the transformation of unstable oscillations into limit-cycles of smaller amplitudes (in agreement with experimental data from the literature). The presence of the shape-memory material is qualitatively similar in effect, but structurally introduced via hysteretic damping of reversible austenitic-martensitic phase transformation. The results also depict the attractiveness of combined structural and aerodynamic nonlinearities to airfoil-based energy harvesting purposes, predicting bounded oscillations at higher post-flutter airflow speeds when compared with cases for isolated structural or aerodynamic nonlinear behaviors. Although no attention is pay to the quantitative amount of electrical power obtained (not included in the scope of this study), the predicted operating envelope of the combined nonlinear effects considered here seems superior to that obtained from other previously investigated strategies.
Keywords
Aeroelasticity, Beddoes-Leishman, dynamic stall, smart materials, nonlinear behavior, Unsteady Aerodynamics
