DISPERSION PROPERTIES OF SIMPLE 3D FINITE ELEMENTS.
- Resource Type
- Article
- Authors
- Johnson, Erland
- Source
- Communications in Numerical Methods in Engineering. Feb95, Vol. 11 Issue 2, p97-103. 7p.
- Subject
- *WAVES (Physics)
*NUMERICAL analysis
*FINITE element method
*MATRICES (Mathematics)
*ALGEBRA
*DISPERSION (Chemistry)
- Language
- ISSN
- 1069-8299
The dispersion properties of plane waves, propagating in an infinite uniform mesh with linear cubic 3D finite elements, are investigated. Time discretization is performed with the central-difference time- stepping scheme in combination with lumped mass matrices. The stiffness matrices are integrated analytically with different integration schemes, and dispersion relations are derived. The results show that the stiffness integration scheme can be chosen to reduce dispersion and improve the isotropy of wave propagation. It is also observed that the numerical wave speed becomes zero along certain wave propagation directions for specific wave numbers. [ABSTRACT FROM AUTHOR]