Near-field Ferromagnetic Object Detection Based on 3D Magnetic Imaging

doi:10.19596/j.cnki.1001-246x.7966

Abstract

Abstract: We propose a method for three-dimensional inversion imaging of unknown magnetic sources in near-field conditions. Considering that most magnetic sources are not only magnetized with background magnetic field, but also have strong remanence, we convert magnetic field on observation surface into magnetic field vector anomaly modulus, and establish objective function to optimize solution to get the best match for magnetic field characteristics. Simulations and experiments show that the method eliminates effectively influence of residual magnetism on inversion results, and realizes imaging of magnetic susceptibility distribution of multiple magnetic sources in near field. It shows that the proposed method can be used to detect position and shape of unknown magnetic body.

Key words: magnetic inversion, magnetic sources detection, magnetic anomaly, magnetic anomaly modulus

CLC Number:

P318

LI Jian, JIN Chunxing, ZHANG Yu, HUANG Xinjing. Near-field Ferromagnetic Object Detection Based on 3D Magnetic Imaging[J]. CHINESE JOURNAL OF COMPUTATIONAL PHYSICS, 2020, 37(1): 88-96.

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