Modified integration rules for reducing dispersion error in finite element methods Original Research Article

This paper describes a simple but effective technique for reducing dispersion errors in finite element solutions of time-harmonic wave propagation problems. The method involves a simple shift of the integration points to locations away from conventional Gauss or Gauss–Lobatto integration points. For bilinear rectangular elements, such a shift results in fourth-order accuracy with respect to dispersion error (error in wavelength), as opposed to the second-order accuracy resulting from conventional integration. Numerical experiments involving distorted meshes indicate that the method has superior performance in comparison with other dispersion reducing finite elements.