Flutter Investigation of Isotropic 3-D Wings

Document Type : Original Article


1 Syrian Armed Forces, Syria.

2 Egyptian Armed Forces, Egypt.

3 Prof. Cairo University, Egypt.


The aeroelastic characteristics of wing depend upon the relationship between its aerodynamic and structural properties of the wing box. In the present work the wing box structure has been modeled using linear equivalent plate approach. The mass and stiffness matrices are calculated for a wing composed of skin, spars, and ribs based on simple polynomial functions. The static and dynamic responses to external loads are calculated for a short plate, and a wing box. The doublet point method has been used for calculating the effect of unsteady aerodynamic loads on harmonically oscillating wing in subsonic flow. Using the standard eigenvalue methodology, the solutions for the resulting complex eigenvalue problem are obtained. The V-g method has been used for determining the flutter speed of rectangle wing by calculating the natural frequencies and damping ratios. The obtained results show good agreement with published results. A parametric study has been carried out to obtain the effect of changing the thickness of skin on the flutter speed. The influence of the aspect ratio on the wing flutter speed has been shown that the flutter speed decreases when the aspect ratio increases.