基于光纤光栅的海水剪切流速传感器

A new shear sensor for ocean based on optical fiber grating

设计了一种基于光纤光栅的新型剪切流传感器,主要包括光纤光栅压力传感机构和翼型探针。湍流对翼型探针产生力的作用,探针将受力传递给等强度悬臂梁使其产生变形,从而使粘贴在悬臂梁两侧的光纤光栅中心波长改变。通过测量两个光纤光栅中心波长改变量的差值,得到湍流的横向脉动速度。双光纤光栅的设计有效消除了温度的影响,解决了光纤光栅的交叉敏感问题。该传感器的空间分辨率为2 cm,采用ANSYS软件对传感器内部结构进行模态分析,得到空气中固有频率为344.26 Hz。经测试传感器灵敏度为。实验表明,传感器能够实现对湍流脉动的响应,实验与理论符合较好,且结构简单,抗电磁干扰,在海洋复杂电磁环境下的湍流测量领域,具有一定的应用前景。

Designing a new shear probe for ocean based on optical fiber grating in this paper,which mainly including fiber grating pressure sensor and airfoil probe. The airfoil probe transmits the force which caused by turbulence to the isosceles triangle cantilever and then the force changes the structure of the cantilever,which causes distortion. The distortion leads to the difference of central wavelength shift. By calculating this difference,the cross stream velocity can be obtained. The design of double fiber gratings wakens the influence of temperature effectively and solves the problem of cross sensitive. The spatial resolution of the sensor is 2 cm,and the natural frequency of the air is 344. 26 Hz can be obtained from the modal analysis of internal structure of the sensor using ANSYS software. The results show that the sensor can response to the turbulent fluctuation effectively and experimental results coincident well with theoretical analysis. The sensor has brief structure,electromagnetic anti-interference ability and has a great application prospect in the field of turbulence measurement under complex ocean electromagnetic environment.