A semi-analytical method for identification of thin elastic plate parameters basing on LWM

  • Ewa Pabisek
  • Zenon Waszczyszyn
  • Łukasz Ambroziński

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.

Keywords

Structure Health Monitoring, non-destructive method, Lamb waves, dispersion curve, modes of vibration, elastic isotropic and homogenous plate, dentification of plate parameters,
Published
Jan 25, 2017
How to Cite
PABISEK, Ewa; WASZCZYSZYN, Zenon; AMBROZIŃSKI, Łukasz. A semi-analytical method for identification of thin elastic plate parameters basing on LWM. Computer Assisted Methods in Engineering and Science, [S.l.], v. 21, n. 1, p. 5-14, jan. 2017. ISSN 2299-3649. Available at: <https://cames.ippt.pan.pl/index.php/cames/article/view/50>. Date accessed: 07 july 2020.
Section
Articles