Periodic Properties of 1D FE Discrete Models in High Frequency Dynamics

Table 1

Average errors of frequency spectra of an isotropic rod of free ends for various types and degrees of approximation polynomials —a numerical model of 736 DOFs according to the elementary theory of rods [36] used for calculations by the TD-FEM ( km/s,  m).

Polynomial type	Polynomial degree	[%]	[%]
Chebyshev	1	3.47	9.92
	3	0.44	11.73
	5	0.13	15.36
	7	0.05	18.75
Legendre	1	3.39	12.76
	3	0.25	3.81
	5	0.06	8.95
	7	0.02	13.01
B-spline	3	0.01	0.85