Iterative solution of boundary element equations for the exterior Helmholtz problem

In this paper an efficient boundary element method for the determination of the acoustic field around arbitrary-shaped finite structures immersed in an infinite homogeneous acoustic medium is studied. The direct boundary integral equation due to Burton and Miller is employed to overcome the nonuniqueness of solution associated with the classical boundary integral formulations of the exterior Helmholtz equation. The choice of the coupling parameter in the Burton and Miller formulation is discussed in order to minimize the condition number of the boundary integral equation. Numerical results are presented for the problem of acoustic radiation from several structures of practical interest.