Detailed Numerical Study of Free Vibration Analysis of Plates

Abstract

Plates are widely used in aircraft, ship building, boiler and automobile applications. It is important to study the vibration characteristics of the plates in order to avoid the resonance in their working condition. Because catastrophic failure occurs in resonance condition due violent vibrations. So to avoid these resonance condition vibration analysis of plates are very important. In this article the modal frequencies and mode shapes of the plates were analysed numerically using ANSYS. Structural steel is considered as the plate material. All edges clamped (CCCC) and all edges free (FFFF) boundary conditions were considered for the study. The effect of parameters such as aspect ratio, thickness, area and shape of the plates on natural frequency was studied. The aspect ratios of 1, 1.5, 2 and 2.5 keeping the surface are same, is considered for the study. Plates of thickness 1 mm, 1.5 mm, 2 mm and 3 mm are analysed. The effect of shape of the plate is studied by considering various shapes like square, circular, equilateral triangle and right angular triangle with same area. It is observed that the natural frequency increases with increase of aspect ratio and thickness. As the surface area increases the natural frequency decreases. The values of natural frequencies of the plates descend in the order of circular, equilateral triangular, square and right angled triangular shapes for all edges free. Whereas the values of natural frequencies of the plates ascend in the order of circular, square, equilateral triangular and right angled triangular shapes for all edges fixed conditions.