On free vibration of laminated skew sandwich plates: A finite element analysis

Abstract

The present work emphasizes the determination of the fundamental frequency of skew sandwich plates with orthotropic core and laminated facings using different design parameters. Finite elements CQUAD4 and CQUAD8 of MSC/NASTRAN are used for obtaining fundamental frequencies, which are validated against available literature results. The influence of the skew angle, the ratio of the length-to total thickness (a/h) of the sandwich plate, and the ratio of the thickness of the core to face sheet (tc/th) on the fundamental frequency of skew sandwich plates are studied. Also, the influence of parameters such as the number of layers in the face sheet, laminate sequence, and fiber orientation angle on the fundamental frequency of laminated skew sandwich plates have been studied. It is found that the CQUAD8 element yields better results than the CQUAD4 element in the present study. The fundamental frequencies are found to increase with the increasing skew angle. The variation in fundamental frequency is negligible when the number of layers is large in the face sheet.

Keywords

• fundamental frequency
• non-dimensional frequency parameter
• skew sandwich plate
• skew angle
• antisymmetric laminate
• fiber orientation angle