Assessment of the ellipsoidal shell model for ship magnetic signature

Abstract

There is described and assessed the ellipsoidal shell model for solving the ship's magnetic signature. This model relies on the premises of equating the mass of magnetic materials used in the ship hull construction with the mass of material of the ellipsoidal shell. The magnetic field is computed in a horizontal plane situated below the analyzed body, starting from the solution to Laplace's equation formulated in the ellipsoidal coordinate system, and by applying the variable separation method. The field computation is performed in the situations: the external field is parallel to the ellipsoid's main axis and perpendicular to it, respectively. The model is analyzed by comparing the computation results to the numerical model constructed in Ansoft Maxwell environment, and, finally, to a set of measurements performed on the actual ship.