The Effect of structural layout on the supersonic flutter characteristics of a fighter wing

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2018
Okumuş, Başak
The increase in flexibility of modern aircraft structures requires the aeroelastic effects be taken into consideration from the very beginning of the design phase in order to escape expensive iterations during the subsequent design phases and lower the required weight penalties resulting from compliance to certain aeroelastic requirements. Therefore, to be able to predict the supersonic flutter velocity is important in the preliminary design phase of fighter aircraft to increase design efficiency. In the first phase of the thesis study, the supersonic aerodynamics required for the flutter calculations are derived for a typical section wing section model using the application of Possio’s theory proposed by Garrick and Rubinow and the supersonic Piston theory. A code is developed applying these theories and it is used to estimate the supersonic flutter speed of a finite plate wing model. In the second phase of the study, the commercial aeroelastic solver ZAERO is utilized to calculate the flutter speed of the weakened AGARD 445.6 Wing. Finally, a fighter wing model is created and its various layout options are analyzed in terms of their effect on supersonic flutter speed with ZAERO. The spar number and orientation, the skin ply orientation and the effect of an external mass is analyzed to observe their effects on the supersonic flutter speed

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Citation Formats
B. Okumuş, “The Effect of structural layout on the supersonic flutter characteristics of a fighter wing,” M.S. - Master of Science, Middle East Technical University, 2018.