脉冲磁激励的磁声效应和热声效应的仿真研究

发布时间：2018-02-01 13:33

  本文关键词： 磁声效应 热声效应 感应式磁声成像 磁热声成像 脉冲磁场　出处：《生物医学工程学杂志》2017年01期 　论文类型：期刊论文

【摘要】：我们根据电磁场辐照低电导率样本时电磁场和声波场之间的耦合关系,对脉冲磁激励的磁声效应和热声效应展开研究。本文基于电磁场理论和声波传播理论知识,推导了脉冲磁激励的声压波动方程;构建二维载流线圈和低电导率圆形薄片模型以模拟成像物理环境,利用有限元方法分析瞬态电磁场;并且根据电磁场仿真结果,进行磁声效应和热声效应所产生的声场仿真计算。仿真结果表明,微秒级高斯脉冲磁场激励下,低电导率样本中热声效应比磁声效应大,且起主要作用;微秒级高斯脉冲磁场和0.2 T静磁场激励下,低电导率样本中热声效应和磁声效应共存。该研究为感应式磁声成像和磁热声成像的进一步应用奠定了基础。
[Abstract]:According to the coupling relationship between electromagnetic field and acoustic field when irradiated by electromagnetic field with low conductivity sample. The magnetoacoustic and thermoacoustic effects of pulsed magnetic excitation are studied. Based on the theory of electromagnetic field and the theory of acoustic wave propagation, the wave equation of sound pressure under pulsed magnetic excitation is derived. A two-dimensional current-carrying coil and a low-conductivity circular thin slice model were constructed to simulate the imaging physical environment and the transient electromagnetic field was analyzed by finite element method. And according to the results of electromagnetic field simulation, the simulation results of magnetoacoustic effect and thermoacoustic effect are carried out. The simulation results show that, under the excitation of microsecond Gao Si pulse magnetic field. The thermoacoustic effect in low conductivity samples is larger than that of magnetoacoustic effect and plays a major role. Under the excitation of microsecond Gao Si pulse magnetic field and 0.2 T static magnetic field, thermoacoustic effect and magnetoacoustic effect coexist in low conductivity samples. This study lays a foundation for the further application of inductive magnetoacoustic imaging and magnetothermoacoustic imaging.
【作者单位】： 中国科学院电工研究所;中国科学院大学;
【基金】：国家自然科学基金(51137004,51477161,61427806)
【分类号】：R312
【正文快照】： 引言长期以来,生物组织电特性的研究是学者关注的焦点。许多研究表明,不同的正常组织以及器官之间、正常组织与病变组织之间的电特性具有较大的差异[1]。例如正常乳腺组织的电导率是0.4 S/m,但是癌变的乳腺组织的电导率是4 S/m[2-4]。因而利用这一性质可以了解生物组织生理和，

本文编号：1481975