Study of flutter on a composite UAV wing

Abstract

A study of flutter of the VAV composite wing has been done by considering the aeroelasticity phenomenon which involves the dynamic instability of a structure which able to lead a catastrophic failure. To prevent any failure, various design effects and materials parameters of the wing structure for a composite VAV wing are being considered in the study as it able to give a significant effect towards the flutter. The flutter velocity can be obtained by deriving the equation from the binary wing model which governs by mathematical equation related to the effect of aerodynamic damping and stiffness as well as structural damping and stiffness. The most important parameters in this study is the heaving stiffness, Ku and pitching stiffness, Ke which is resulted from the derivation of the full aeroelastic equation of motion. The stiffness can be obtained by simulating or analysis of the wing structures in the finite element software, Abaqus/CAE 6.13-EFI where the natural frequencies of the bending and torsional can be obtained. The equation of full aeroelastic motion can be solved by finding its eigenvalue from the MATLAB software by writing the script file. The flutter speed can be obtained from the intersection point of heaving and pitching frequency across the speed as well as at the point where the damping ratio is zero along the air speed. From the study, a sets of spar and ribs at certain location across the wing has been proves to produce a higher flutter velocity which is 162.31 m/s.