Research on Magnetic Anomalies Induced by Submerged Moving Bodies based on Potential Flow Theory

This study investigates the current density induced by the wake velocity field of submerged moving bodies (SMBs) during navigation and the resulting anomalous magnetic fields. Simulation results demonstrate that when an SMB navigates at 360 m depth with a speed of 25 knots, it can induce a 3.8 nT magnetic field on the sea surface and tens of nanotesla-level magnetic fields underwater, which are detectable by existing inductive or quantum magnetometers with noise levels below the measurement resolution of 0.1 nT. This research contributes to understanding magneto-hydrodynamic anomalies induced by underwater moving objects and developing novel non-acoustic detection methodologies for submarine surveillance.