海水可以被看成是磁流体并能传播磁声波,运用建立的海洋磁流体力学模型,从理论上通过声波密度扰动驱动下的离子密度群聚现象,以及磁场脉冲驱动下的离子密度群聚现象的分析,得到磁声波的微观特征,即在地磁场的作用下,声波传播的粒子密度极大值前后会形成离子密度漂移电流,海水的盐离子将群聚到中性粒子密度极大值区,而当在海水中激励一个磁脉冲时,盐离子将产生磁场梯度漂移运动,使得盐离子向磁脉冲极大值区域群聚。在此基础上,探讨海水中无人潜航器激励磁声波的传播特征,提出通过高灵敏磁感应搜索线圈探测磁声波传播时产生的磁场扰动,从而实现一种有效的高灵敏非声探测潜航器的方法。
Seawater can be regarded as a magnetic fluid and can propagate magneto-acoustic waves. Using the established marine magneto-hydrodynamic model, theoretically through the ion density clustering phenomenon driven by the acoustic wave density disturbance, and the ion density cluster driven by the magnetic field pulse. Through the analysis of the aggregation phenomenon, the microscopic characteristics of the magneto-acoustic wave are obtained, that is, under the action of the geomagnetic field, the ion density drift current will be formed before and after the maximum particle density of the sound wave propagation, and the salt ions of the seawater will be clustered to the maximum neutral particle density. When a magnetic pulse is excited in seawater, the salt ions will produce a magnetic field gradient drift motion, which makes the salt ions cluster to the maximum value region of the magnetic pulse. On this basis, the propagation characteristics of magneto-acoustic waves excited by unmanned submersibles in seawater are discussed, and a highly sensitive magnetic induction search coil is proposed to detect the magnetic field disturbance generated during the propagation of magneto-acoustic waves, so as to realize an effective high-sensitivity non-acoustic detection submarine method of the device.
2023,45(5): 124-131 收稿日期:2022-10-24
DOI:10.3404/j.issn.1672-7649.2023.05.023
分类号:P754
基金项目:湖北省弱磁探测工程技术研究中心资助项目(1640084)
作者简介:步远恒(1995-),男,硕士研究生,主要从事弱磁探测研究