Experimental and Theoretical Study of Gust Response for High-Aspect-Ratio Wing

A nonlinear response analysis of a high-aspect-ratio wing aeroelastic model excited by gust loads is presented along with a companion wind-tunnel test program. For the wind-tunnel tests, a high-aspect-ratio wing aeroelastic experimental model with a slender body at the tip has been constructed, and a rotating slotted cylinder gust generator has been used to generate a gust excitation field. A LabVIEW 5.1 measurement and analysis system is used to measure the gust response, flutter boundary, and limit-cycle oscillation behavior. Structural equations of motion based on a nonlinear beam theory are combined with the ONERA aerodynamic stall model to study the effects of geometric structural nonlinearity and steady angle of attack on nonlinear gust response of high-aspect-ratio wings. Also a dynamic perturbation analysis about a nonlinear static equilibrium is used to determine the small perturbation flutter boundary. The fair to good quantitative agreement between theory and experiment demonstrates that the present analysis method has reasonable accuracy.