隧道支护架对核磁探测影响的研究
Study on Tunnel Supporting Frame for Nuclear Magnetic Resonance Detecting Impact
王应吉 1赵治辉 1林君 1孙淑琴1
作者信息
- 1. 吉林大学地球信息探测仪器教育部重点实验室,仪器科学与电气工程学院,吉林长春130061
- 折叠
摘要
核磁共振超前探测在隧道中因受到支护架的影响,使发射电流减小,影响激发场的建立和信号的接收,以至于探测结果不精确.为了定量讨论这种影响,通过分析支护架与探测线圈物理关系、电磁场相互影响等,建立了变压器模型.简化电路模型,利用基尔霍夫电流定律建立核磁共振发射线圈的电阻增量、电感减量与隧道支护架电阻、电感的关系公式,得知发射电流增加和减少的量化分析.分析支护架与发射线圈的位置关系,推导出支护架与发射线圈的互感系数公式,根据电阻增量、电感减量以及支护架与发射线圈的互感系数,可以得到支护架的电阻以及电感.通过实验论证,实测结果与理论结果相吻合,这对后续反演提供了依据.
Abstract
The tunnel supporting frame has a strong impact on the nuclear magnetic resonance detecting.The emission current decreases,at the same time,the establishment of the excitation field and the reception of the signal are also influenced,hence,the detection results is imprecise.Combining with the transformer model,through Kirchhoff's current law,the relationship is obtained between the increasing amount of resistance of emission coin and the decreasing amount of inductance and the supporting frame resistance and inductance.The mutual inductance of supporting frame and the transmitter coil is calculated.According to the addition and the reduction,the resistance and inductance are calculated.Demonstrated by experiment,the measured and calculated results are consistent,the results provide a basis for the inversion of NMR signals.
关键词
核磁共振/线圈/支护架Key words
nuclear magnetic resonance (NMR)/coil/supporting frame引用本文复制引用
基金项目
科技部科技创新工作方法项目(3B810Z950537)
国家重大科学仪器设备开发专项(2011YQ030133)
出版年
2014
NETL
NSTL
维普
万方数据