Flutter characteristics of plate like structures

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2014
Dalmış, Mevlüt Burak
In this study, flutter characteristics of plate like structures in incompressible flow are investigated by comparing the results of commercial flutter analysis program ZAERO© with wind tunnel tests conducted in Ankara Wind Tunnel (ART). Firstly, a rectangular polycarbonate (PC) plate, 5x125x1000 mm in dimensions, is investigated. In this case, analysis and test results are in good agreement with each other. Second test item is a 1/10 scaled F-16 wing like PC plate. In this case, the plate is capable of carrying external stores in different dimensions. Two different flutter analysis are conducted for this plate by using two different fixed end structural boundary conditions. In the first boundary condition, the plate is fixed from its bottom; in the second boundary condition, the plate is fixed from both bottom and side surfaces of the plate. Moreover, modal test is conducted by impact hammer for this test item. Results of this modal test indicates that modal analysis result using the first structural boundary condition, in which only bottom of the plate is fixed, is more realistic than the modal analysis result using the second structural boundary condition, in which the bottom of the plate with its side surfaces are kept fixed. Therefore, even if the modal analysis results are used for the flutter analysis, a modal test should be conducted in order to validate the modal analysis results to have accurate flutter analysis results. A comparison between two different solution methods of ZAERO©, namely K-method and g-method, is also done by using the results of second test item.

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Citation Formats
M. B. Dalmış, “Flutter characteristics of plate like structures,” M.S. - Master of Science, Middle East Technical University, 2014.