大型铁磁性物体近场磁异常场数值仿真

磁异常探测是一种在地球物理领域有着广泛应用的探测方法，磁异常场的空间分布规律信息是磁异常探测的主要理论依据。对矩形铁磁性物体空间磁场模型进行了推导，利用ANSYS Maxwell分析了大型铁磁性物体近场的磁异常场空间分布规律。针对不同地磁场方向条件，得到了近场空间磁感应强度总量分布及矢量分布规律，揭示了在不同条件下磁感应强度模量场和矢量场都具有普遍的对称性和规律性。通过对仿真模型进行缩比试验，测量了类似条件下模型近场的磁感应强度模量场和矢量场信息，验证了仿真得到的磁异常场空间分布规律的一致性和正确性。

Numerical simulation of near-field magnetic anomaly field for large-scale ferromagnetic objects

Magnetic anomaly detection is a widely used approach to detect ferromagnetic objects, which is mainly based on the spatial distribution of magnetic anomaly field. The spatial magnetic field model of rectangular ferromagnetic object is derived. The spatial distribution of the magnetic anomaly field in the near-field of the large-scale ferromagnetic target is analyzed using ANSYS Maxwell. For different geomagnetic field direction conditions, the laws of magnitude distribution and vector distribution of the magnetic induction in the near-field are obtained, which reveals a universal symmetry and regularity in magnetic induction modulus field and vector field. The shrinkage ratio experiment is conducted and the magnitude distribution and vector distribution of the magnetic induction in the near-field of model are measured in similar conditions, which validates the consistency and correctness of the spatial distribution law of magnetic anomaly field.