雷击建筑物环境下高灵敏度光纤磁场传感技术研究

With the development of society, there are more and more large-scale buildings and they will be moving towards an intelligent direction. Sensor technology plays a key role in the building intelligent system. The existing sensing devices are electrically powered. When lightning strikes the intelligent architecture, a stronger magnetic field will be generated inside, which may lead to an equipment failure. In order to effectively monitor the magnetic field from lighting, this project proposed a magnetic field measurement method combining sensitive materials and a special optical fiber. For the sensitive materials, a novel magnetic fluid grating was presented. Compared with the traditional gratings, it exhibits the advantages such as easy formation and better magnetic tunability. In the study, dissipative particle dynamics method was presented to simulate the formation process of the magnetic fluid grating. In addition, the magnetic fluid grating was fabricated and the experimental observation system was established. The formation process of the magnetic fluid grating was observed. For the special optical fiber, a D-shaped optical fiber was used as a carrier to excite a surface plasma wave. Finally, a novel magnetic field sensor combined the magnetic fluid grating and the D-shaped optical fiber was proposed. The modulation of the surface plasmon wave by the magnetic fluid grating was studied, and the resonance characteristic as a function of the magnetic field was analyzed. The project based on sensitive materials, electromagnetics, optics and sensing technology, has an obvious innovation, novel interdisciplinary and great prospect.

随着社会的发展，大型综合建筑物越来越多，并朝着智能化方向发展。传感技术在建筑智能化中起着决定作用。现有的传感装置大多采用电力驱动，这样当遭受雷击时，会在建筑物内部产生较强磁场，导致传感装置失效。为了有效监控雷击所产生的磁场范围，本课题提出一种磁敏感材料结合特种光纤的磁场测量方法。在敏感材料方面，提出一种新型磁流体光栅结构，与传统光栅相比，这种结构的形成不仅不需要复杂的制备工艺，还具有很好的磁调谐性。采用耗散粒子动力学方法，模拟磁性粒子形成磁流体光栅的过程；制备磁流体光栅，搭建磁流体光栅的实验观测系统，观察磁流体光栅形成过程；在特殊光纤方面，采用D型光纤作为载体激发表面等离子体波。最后提出将磁流体光栅与D型光纤相耦合的磁场传感方法，分析磁流体光栅对表面等离子体波的调制作用，研究共振特性随磁场的变化。本项目是基于敏感材料、电磁学、光学和传感技术，具有明显的创新性、多学科交叉性和实际应用前景。

本项目针对智能建筑在雷击环境下产生磁场干扰传感装置的问题，提出一种磁敏感材料结合特种光纤的磁场测量方法，并实现了磁场传感应用的相关研究；本项目已经完成的研究内容包括：采用耗散粒子动力学方法，模拟了磁性粒子形成磁流体光栅的过程；搭建磁流体微观结构的实验观测系统，验证了磁流体形成光栅结构的理论，并且证实了这种结构具有磁调谐特性；采用D型光纤作为载体激发表面等离子体波，建立了磁流体光栅与D型光纤相耦合的磁场传感模型，验证了磁流体光栅对表面等离子体波的调制作用，以及共振特性随磁场的变化。本项目针对敏感材料及特种光纤的相关研究成果，将为下一步D型光纤在智能建筑结构健康监测的其他方面应用研究提供理论参考和实验依据，极大丰富特种光纤技术的研究内容，促进特种光纤在智能建筑中的应用发展。