This chapter extends the modified dual-level fast multipole algorithm
(MDFMA) to the field of acoustics. The Burton-Miller formulation is applied to
overcome non-uniqueness at internal resonance. The MDFMA based on the Burton-
Miller formulation is here tested by a series of complex engineering cases. It is
observed that the MDFMA performs 44% faster than COMSOL in the analysis of
acoustic scattering characteristics of an A-320 aircraft, and 56% faster than the fast
multipole boundary element method in the analysis of underwater acoustic scattering
characteristics of the Kilo-class submarine.
Keywords: Modified dual-level algorithm, Boundary element method, Fast
multipole method, Three-dimensional sound field.
