Je. Caruthers et al., GREEN-FUNCTION DISCRETIZATION FOR NUMERICAL-SOLUTION OF THE HELMHOLTZ-EQUATION, Journal of sound and vibration, 187(4), 1995, pp. 553-568
A discretization method based on free space Green function interpolati
on with a minimum L(2) norm property has been developed for numerical
solution of the Helmholtz equation. It has been shown to produce accur
ate solutions with less than three points per wave, which implies a ma
nyfold improvement in solution efficiency over previous methods. The a
ccuracy of the method does not break down formally until the grid reso
lution approaches two points per wave. (C) 1995 Academic Press Limited
.