It was demonstrated that a tensile force in a member increases its flexural stiffness and hence the frequency of vibration. In contrast, a compressive force was found to have the opposite effect. The numerical experiments performed using the scheme developed in this study demonstrated that an increase in the flutter speed is achievable through the proper location, magnitude and type of prestress forces induced within the wing structure. The strain energy and modal energy objective functions used in the experiments demonstrated an increase of the flutter speed by 16% and 26%, depending upon the objective function used, prior to the onset of divergence. Realistically achievable prestress forces were realized for these increases. The concept of stiffness modification by inducing an optimal distribution of prestress can be effectively used to achieve the desired dynamic characteristics in a structure. Such modification can be done either by passive or active means.
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