Evaluation of a Numerical Model for Ship Magnetic Signature Induced by an External Field

In order to assess the ship magnetism induced by the Earth's magnetic field, a virtual ship was built, which was further analyzed in the Ansoft Maxwell environment. The virtual ship model's main dimensions and material characteristics were similar to the ones of the actual ship. The ship model was considered a metallic shell of 12 mm width. The analysis studied the impact on ship magnetization of an external magnetic field oriented vertically and afterwards horizontally. Finally, there was determined the magnetization induced by the geomagnetic field, consisting of the previously considered components. The external magnetic field values were chosen from the main geomagnetic field reference model (IGRF) for the area near the Romanian coast of the Black Sea. Simulation results were compared to a set of measurements performed on the ship itself, and differences between simulated and measured values were discussed.