복합재료 날개의 진동 특성

Abstract

The analysis of vibration characteristics for various shaped composite wings has been performed by the finite element method based on shear deformable theory. The wing is composed of Graphite/Epoxy composite materials. Symmertric stacking sequence has been adapted in this analysis. This paper presents the effects of sweptback angles and fiber orientation on the vibration characteristics. The first mode of sweptback wing is the first bending mode regardless of the fiber orientation. However, the second mode changes from the 1st torsional mode to the 2nd bending mode as the fiber angle increases. In the case of 40 degree sweptback wing, the 2nd and the 3rd natural frequencies become very close when the fiber angle is near 8 degree. In the higher modes, we can see the similar mode shape changes due to the fiber orientation.