地下铁质管线的地面高精度磁测数值模拟  

Numerical simulation of surface high-precision magnetic detection of underground metal pipes

作　　者：张颖颖[1] 刘得军[1] 李轶 郭智勇[1] 王政[1] 

机构地区：[1]中国石油大学(北京)油气资源与探测国家重点实验室地球物理与信息工程学院,北京102249

出　　处：《中国矿业大学学报》2016年第1期182-188,共7页Journal of China University of Mining & Technology

基　　金：国家自然科学基金项目(41374151)

摘　　要：为了能够准确探测地下铁质管线,利用多物理场有限元软件Comsol建立了铁质管线的磁异常响应的三维数值模拟模型,将均匀磁化球体模型的数值解与解析解进行对比,验证了计算程序的准确性,分析了管道的相对磁导率、长度、外径和走向对磁异常信号的影响规律.由模拟结果可知,管道的相对磁导率和外径与磁异常信号的幅值呈正相关,不影响其基本波形;当管道长度较长时,中间段磁异常变化很小;当管道长度较短时,中间段磁异常变化剧烈;管道走向可严重影响管道磁异常信号的幅值和波形.管道端点处具有较大的正磁异常或负磁异常,可通过连接两端磁异常的顶点和谷点,确定管道走向.通过模型检验,表明化极处理可以有效识别管道的埋深和平面位置.To detect underground metal pipes precisely,a 3Dnumerical model was built to study the magnetic response of the underground metal pipes using multiphysics finite element method（FEM）software Comsol.The numerical solutions of a uniformly magnetized sphere were compared with the analytical solutions and results validated the accuracy of the computation program.Based on the model,the relative permeability,length,outer diameter and direction of the pipe were analyzed.Numerical simulation results show that the relative permeability and outer diameter are positively relative to the magnetic anomaly amplitude,but have nothing to do with the magnetic anomaly phase degree;when the pipe is long,the magnetic anomaly at the middle of the pipe changes little;when the pipe is short,the magnetic anomaly at the middle of the pipe changes dramatically;the pipe direction has great effects on the amplitude and shape of the magnetic anomaly.Big amplitude of magnetic anomaly can be detected at two ends of the pipe,and the direction of pipe can be determined by connecting the peak point and valley point at both ends.Also,experiment results show reduction to the pole helps effectively identify the depth and horizontal position of the pipe.

关 键 词：磁异常 铁质管道 有限元 响应规律 化极 

分 类 号：P631[天文地球—地质矿产勘探]