Modal and Aeroelastic Analysis of A High-Aspect-Ratio Wing with Large Deflection Capability

Subject Areas : Mechanical Engineering

R. Koohi ¹ , H. Shahverdi ² , H. Haddadpour ³

1 - Department of, Mechanical and Aerospace Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran
2 - Department of Aerospace Engineering and Center of Excellence in Computational Aerospace, Amirkabir University of Technology, Tehran, Iran
3 - Department of Aerospace Engineering, Sharif University of Technology, Tehran, Iran

Received: 2014-08-19 Accepted : 2014-10-22 Published : 2015-03-01

Keywords: FEM, Jone's Approximate Unsteady Aerodynamics, Wing Aeroelastic Stability, Large Deflection,

Abstract :

This paper describes a modified structural dynamics model for aeroelastic analysis of high-aspect-ratio wings undergoing large deformation behavior. To gain this aim, a moderate deflection beam model is modified with some important large deflection terms and then coupled with a state space unsteady aerodynamics model. Finite element method is used to discretize the equations of motion. A dynamic perturbation equation about a nonlinear static equilibrium is applied to determine the flutter boundary. The obtained results show good agreement in comparison with the other existing data such as high-altitude long-endurance (HALE) wing and Goland wing. It is found that the present aeroelastic tool have a good agreement in comparison with valid researches and also considering the effect of the geometric structural nonlinearity and higher order nonlinear terms on the flutter boundary determination is very significant.

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