ABSTRACT
For the analysis of wave propagation problems by the finite element method, one must take into account the numerical dispersion of waves. In this paper, the numerical modelling of wave propagation by the finite element method is thus analyzed and discussed for linear constitutive laws. Numerical dispersion may increase the numerical error during the propagation process as the wave velocity (phase and group) depends on the features of the numerical model. Numerical dispersion is analyzed herein for 1D and 2D cases considering the influences of element size, element type, wave type… For 2D-cases, the angle of incidence is shown to have a strong effect on numerical dispersion (error). The classical assumptions giving the maximum value of element size to wavelength ratio are discussed. The accuracy of high order 15-node finite elements towards numerical dispersion is also considered.
