Damping study of composites using wavelet analysis

摘要

This study aims at estimating the damping parameters of composite beams. The composites used are glass-fiber-reinforced epoxy (GFRE), glass-fiber-reinforced polyester (GFRP), and carbon-black-filled epoxy (CBFE). The Morlet wavelet transform is used to investigate the system response analytically. A single-degree-of-freedom system under forced vibration is considered. The procedure employs a relationship between damping ratio, natural frequency, and continuous wavelet analysis of the system response. It is observed that the validity of the relationship depends on the translation factor, scaling factor, and central frequency of the Morlet wavelet. Experimental results are used to verify the wavelet analysis. The error obtained in damping ratio and natural frequency is less than 2%, which authenticates the theoretical analysis. Further, the CBFE composite gives better damping properties than the other two types of composite.