Calculation and verification of manifold of baffled hydrophone array based on boundary element method

A model used for calculating the manifold of a baffled hydrophone array mounted on a complicated structure is presented. In the proposed model, the manifold of an arbitrary array is obtained by computing the scattered sound field response of the array elements based on the boundary element method (BEM). Using the calculated manifold, the array element weights are derived using a beampattern optimization algorithm. Therefore, if the measured manifold and the theoretical manifold are known, we can get the measured beampattern and the theoretical beampattern. Watertank experiments were carried out for an arc array mounted on the surface of a half-sphere shell made of rigid aluminum. The results indicate that the measured manifolds are approximately identical to the theoretical manifolds calculated from the proposed model, and the measured beampatterns are also consistent with the theoretical beampatterns. Moreover, the above beampatterns are much better than the beampatterns obtained from phase compensation assuming that the array elements are omnidirectional point hydrophones.