地磁场磁力线可视化种子点选取的磁场强度线积分等分算法

将磁力线按流线进行绘制是地磁场可视化的通用方法. 磁力线种子点的选取 决定了绘制磁力线的疏密, 其疏密程度能否真实反映地磁场强度分布是评价地 磁场可视化效果的关键. 基于磁经圈均匀角度种子点选取算法绘制 的磁力线通常不能客观反映地磁场强度的空间分布, 针对这一不足, 提出一种等分磁场强 度线积分的磁力线种子点选取算法. 利用该算法对地磁场IGRF模型和T96模型 描述的地磁内外源场进行可视化绘制, 对磁力线追踪结果中出现的冗余磁力线 进行过滤, 统计分析了绘制磁力线的空间分布与地磁场强度空间分布的相关性, 结果表明该算法能够较好地实现对地磁场的可视化. 

Seed Point Selection through Equal Line Integral of Magnetic Field Intensity Algorithm for Visualization of Geomagnetic Field

Drawing the magnetic lines as streamlines is a general method of visualizing geomagnetic field. A key factor to evaluate the effect of the geomagnetic field visualization is whether the space distribution of geomagnetic field lines is consistent with that of magnetic field intensity, while the distribution of geomagnetic field lines is determined by seed point selection. The traditional algorithms that select seed points with uniform angles on magnetic meridian circles cannot objectively reflect the space distributions of magnetic field intensity. This paper proposes an algorithm of selecting seed points with equal line integral of magnetic field intensity. The algorithm is applied to draw the geomagnetic field lines with the data from T96 model and IGRF model. The redundant magnetic field lines existing in the result are removed. Statistical analysis and comparison between the space distribution of magnetic field lines and the geomagnetic field intensity reveals that this algorithm can effectively visualize the geomagnetic field.