DEVELOPMENT OF ANALYSIS FRAMEWORK FOR GUIDED ELASTIC WAVE PROPAGATION THROUGH THIN HYPERELASTIC MEMBRANES

Abstract

In this study, the effects of varying various parameters on the dispersive nature on the fundamental modes of Lamb waves through a compressible transversely isotropic hyperelastic plate with one family of fiber and hard magnetic active soft elastomer are studied. The dispersion curves by a numerical framework called Semi Analytical Finite Element (SAFE) method is used. For modeling the hyperelastic material, Gent model is used. The report starts with a brief discussion on the importance of studying dispersion plots. A brief introduction to the hyper elastic models, its various models and the corresponding strain energy functions which are used to derive the elastic moduli, elastic wave propagation, and dispersion are presented. Types of modes of Lamb waves are also discussed. Finally, the phenomenon of acoustoelasticity is also mentioned which is very important in structural health monitoring. After that, there is a comprehensive literature review of various studies done on wave propagation through hyperelastic materials which can be broadly classified into analytical methods and numerical methods. In Chapter 4, derivation of elastic moduli for a fiber reinforced hyperelastic plate and hard magnetic plate are presented. In Chapter 5, the elastic moduli derived, is used to calculate the SAFE formulations is discussed. In Chapter 6, the results obtained from SAFE program are shown comprising of variation of phase velocity with different material and waveguide parameters.