Accurate prediction of unknown corrosion currents distributed on the hull of a naval ship utilizing material sensitivity analysis

This paper presents an efficient approach to determining the corrosion currents distributed on the hull of a naval ship, which offers useful information for the prediction of underwater electric fields and diagnosis of hull corrosion state. To achieve this goal, a material sensitivity formula containing the first-order gradient information of an objective function with respect to the corrosion current is analytically derived by exploiting the augmented Lagrangian method and the adjoint variable method. The validity of the proposed method has been proved through the comparison of the predicted and the measured fields for a test ship model.