An efficient Green's function for acoustic waveguide problems

Efficient implementations of the boundary element method for underwater acoustics should employ Green's functions which directly satisfy the boundary conditions on the free surface and the horizontal parts of the bottom boundary. In the present work, these Green's functions are constructed by using either eigenfunction expansions or Ewald's method. This method is discussed in detail, including an attempt to optimize the value of the parameter b, which splits the integral employed in Ewald's representation. A numerical analysis of the infinite series used in the two-dimensional acoustic waveguide problem is described, considering the following simplifications: the source of acoustic disturbance is time-harmonic, the velocity of sound is constant and the medium in the absence of perturbations is quiescent. Copyright © 2006 John Wiley & Sons, Ltd.