Abstract: In this article, the limit cycle flutter of a two-dimensional wing with an external store system with gaps in their connection is investigated. Applying the linearization method, the flutter boundary curve is gained, according to which the limit cycle phase pictures are acquired by using the 4th Runge-Kutta. Then the differences between the limit cycle flutter and normal cycle vibration are seen obviously. By using the interval analysis method the influence of the uncertainty in structure parameters on flutter boundary is studied. The stochastic finite element method (FEM) is introduced to verify the reliability of the interval analysis method. Moreover, for a fixed speed, the upper and lower amplitudes of the wing-store system with uncertainty are obtained and the influence of the uncertainty is cognized on the limit cycle phase pictures. Then proper control can be performed to restrain that known amplitude of the external store.

Key words: limit cycle flutter, wing with an external store, uncertainty, interval analysis, stochastic FEM