Role of modal interchange on the flutter of laminated composite wings

The vibration and flutter behavior of laminated composite wings are investigated by looking into unexpected blips or abrupt changes occurring at certain fiber angles of the laminate and pinpointing its underlying cause. A modal elimination technique is used to establish the number of dominant normal modes that contribute to the flutter behavior for different ply angles in the laminate. The flutter mode is computed using selective normal modes that were found to be primarily responsible to cause flutter. Contributions from each normal mode to the flutter mode are isolated in each case, and their relative individual contributions are studied. The results are discussed and some conclusions are drawn.