Numerical propagation of spatially distributed acoustic sources using the exterior Helmholtz integral equation

A finite difference approximation of the Helmholtz equation numerically integrated over a measurement surface can determine the acoustic field throughout an entire volume of a homogeneous region outside. This approach has been developed and implemented to study acoustic fields radiating from large immersed structures from pressure data measured over a generalized cylindrical measurement surface. The numerical algorithm is described, and simulation examples are presented. The results show pressure, velocity, and intensity distributions both in the evanescent wave region of the geometric nearfield and in the acoustic farfield