Prediction of the ship’s permanent magnetization – Applied on CFAV Quest


  1. Birsan, M.
Corporate Authors
Defence R&D Canada - Atlantic, Dartmouth NS (CAN)
DRDC Atlantic has an ongoing program looking at developing integrated signature management (ISM) techniques for a variety of platforms. This includes the conversion of the measured platform signatures into source strengths, creating a time-history of these source strengths, and advising the Canadian Forces on how to reduce the detection ranges of these platforms. Military submarines and surface ships are regularly subjected to a treatment called “deperming” that seeks to design the vessel’s permanent magnetization for optimal magnetic silencing. At present, during a ranging operation the permanent magnetization is inferred qualitatively from the performances of the degaussing coils. This study sets out to quantitatively predict the vessel permanent magnetization as the difference between the total (un-degaussed) and the induced magnetization using a combination of measured magnetic signatures and magnetic modeling. A variety of models describing the ship’s magnetization have been developed starting from a single magnetic dipole to sophisticated distributions of magnetic sources. Depending on the complexity of these models, they describe the signature of the magnetized ship at large or small distances from the sensors. Two methods are proposed that correlate the modeling parameters with the ship magnetization for a correct interpretation of the signature. Due to the ship self-demagnetization effect, the induced magnetization is not known. For this reason, a numerical m

Il y a un résumé en français ici.

Report Number
DRDC-ATLANTIC-TM-2008-186 — Technical Memorandum
Date of publication
01 Nov 2008
Number of Pages
Electronic Document(PDF)

Permanent link

Document 1 of 1

Date modified: