기울어짐 정렬불량을 고려한 회전디스크의 진동해석

Abstract

This study investigates the dynamic characteristics of a spinning disk with angular misalignment using finite element method. The angular misalignment in this study is defined as the angle between the axis parallel to the shaft and the axis perpendicular to the disk. The angular misalignment is one of major vibration sources in optical disk drives such as CD-ROM, CD-R, CD-RW and DVD drives. Based upon Kirchhoff plate theory and von-Karman strain theory, three coupled non-linear equations of motion for the spinning disk with angular misalignment are obtained. After transforming these equations into weak forms, the weak forms are discretized by using annular sector finite elements. Applying perturbation method on the discretized equations, natural frequencies of the disk are calculated and the effects of the angular misalignment on the natural frequencies are analyzed. The results show that the angular misalignment causes the mode split of the degenerate modes of the disk.