Finite element analysis for predicting the vibration characteristics of natural fiber reinforced epoxy composites

Abstract Modal analysis is a tool to predict the vibration characteristics such as natural frequencies, mode shapes and viscous damping coefficients of the structures. These characteristics play an important role in engineering design and analysis. In this paper, the prediction of vibration characteristics or modal-modal of cantilever beam made of neat epoxy and various natural fiber composites carried out by using finite element analysis software ANSYS 20.0. In this study, the natural fibers such as jute, banana, coconut coir, hemp and kenaf fibers are used as reinforcement in the epoxy matrix. The size of beam is 160 mm × 20 mm × 3 mm. The volume fraction of fiber is 33.33% taken for all natural fiber composite materials. The natural frequencies, damping factor and frequency response function bode plot are obtained with the help of ANSYS software. The damping factor is found out using half power bandwidth method from frequency response function bode plot. The natural frequency and damping factors of different natural fiber composites are compared with epoxy material. It is found from this analytical study that the damping factor values for each natural fiber composite material have higher values corresponding to each mode than that of epoxy material. Hence, it is concluded that the natural fiber composites have better damping properties than epoxy material. Hemp and kenaf fiber composite materials have similar values of natural frequencies for lower modes (1st mode and 2nd mode) and at higher modes (5th mode and 6th mode) respectively.