A semi-analytical method for identification of thin elastic plate parameters basing on LWM
Journal Title: Computer Assisted Methods in Engineering and Science - Year 2014, Vol 21, Issue 1
Abstract
A new semi-analytical method, discussed in the presented paper, is composed of two stages. Stage A corresponds to the direct analysis, in which the Lamb Waves Measurements (LWM) technique enables obtaining an experimental set of points , where f and k are frequency and wavenumber, respectively. After the preprocessing in the transform space an experimental approximate curve can be formulated. In Stage B the identification procedure is simulated as a sequence of direct analyses. The dimensionless Lamb Dispersion curves are computed by means of the dimensionless simulation curve ksim ( f | par), where the vector of plate parameters par = {E, v, d, p} is adopted, in which Young's modulus E , Poisson ratio v , plate thickness d and density p are used. The main idea of the proposed approach is similar to that in the classical method of error minimization. In our paper we propose to apply the zero error value of relative criterion Reky = 0, cf. formula (15). The formula can be applied for the identification of a single plate parameter, assuming a fixed value of the other plate parameters. This approach was used in a case study, in which Stages A and B were analysed for an aluminum plate.
Authors and Affiliations
Ewa Pabisek, Zenon Waszczyszyn, Łukasz Ambroziński
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