分布式传感光缆温度及应变特性研究
发布时间:2018-03-25 06:30
本文选题:布里渊光时域分析仪 切入点:光缆温度传递 出处:《电子科技大学》2014年硕士论文
【摘要】:光纤传感技术由于其无可比拟的优势,在现代测量技术中受到人们越来越多的重视,尤其是分布式光纤传感技术,其可以实现对被测量长距离、实时性地监测,受到国内外研究学者的重点关注,已经被广泛应用在电力工程、军事防御、周界安防等领域。目前对于提高测量精度在系统方面已经进行过众多研究,然而在实际的测量过程中,光缆对系统的测量精度也产生一定的影响,进而影响系统总体性能,本论文对布里渊光时域分析仪(BOTDA)中光缆的特性进行了理论及实验研究,研究内容主要分为两个方面:一是温度传感光缆的温度传递时间及其对系统响应时间的影响;二是应变传递光缆在不同的材料及布设方式下的应变传递性能。具体研究内容如下:首先介绍了传热学的基本相关理论,在此基础之上分析了温度传感光缆的温度传递机制,并在有限元软件中建立模型进行仿真,接着设计温度传递实验进行验证,仿真与实验结果相吻合,为分析光缆温度传递时间提供了一种方法,并结合BOTDA系统进行光缆与紧包光纤的温度传递对比实验,结果表明光缆在一定条件下会影响系统的响应时间;然后分析了应变传感光缆在不同的布设方式下的应变传递特性:首先分析了埋入式光缆的应变传递原理,建立埋入式应变传递光缆模型,并在有限元软件中对影响其应变传递性能的因素进行仿真分析,结果表明涂敷层的弹性模量越大、厚度越小,光缆的应变传递效果越好,相比之下,护套层材料对应变传递性能的影响较小,可忽略;接着在表面粘贴式光纤光栅(FBG)的应变传递理论基础之上,推导了应变传递光缆在表面粘贴布设方式下的应变传递机制,得到应变传递系数表达式,并在有限元软件中对定点布设和全面粘贴两种方式进行仿真,分别得到其所对应的应变传递系数曲线。本论文的研究结果为工程应用中不同场合光缆的选择提供了一定的方法和指导,有望促进分布式光纤传感系统性能的进一步优化。
[Abstract]:Because of its unparalleled advantages, optical fiber sensing technology has been paid more and more attention in modern measurement technology, especially distributed optical fiber sensing technology, which can realize the real-time monitoring of long distance measurement. It has been widely used in the fields of power engineering, military defense, perimeter security and so on. At present, many researches have been carried out to improve the measurement accuracy in the field of system. However, in the actual measurement process, the optical fiber cable also has a certain influence on the measurement accuracy of the system, and then affects the overall performance of the system. In this paper, the characteristics of optical fiber cable in Brillouin Optical time Domain Analyzer (BOTDA) are studied theoretically and experimentally. The research contents are divided into two aspects: first, the temperature transfer time of the temperature sensing cable and its effect on the response time of the system; Second, the strain transfer performance of the strain-transfer optical cable under different materials and layout. The specific research contents are as follows: firstly, the basic related theory of heat transfer is introduced, and then the temperature transfer mechanism of the temperature sensing cable is analyzed. The model is established in the finite element software for simulation, and then the temperature transfer experiment is designed to verify it. The simulation results are in agreement with the experimental results, which provides a method for analyzing the temperature transfer time of optical fiber cable. The experimental results of temperature transfer between fiber optic fiber and fiber optic fiber show that the response time of the system will be affected by the cable under certain conditions. Then the strain transfer characteristics of the strain sensing cable under different arrangement modes are analyzed. Firstly, the strain transfer principle of the embedded fiber optic cable is analyzed, and the embedded strain transmission cable model is established. The results show that the greater the elastic modulus and the smaller the thickness of the coating, the better the strain transfer effect of the fiber optic cable, and the simulation results of the factors affecting the strain transfer performance in the finite element software show that the higher the elastic modulus and the smaller the thickness of the coating layer, the better the strain transfer effect of the cable. The effect of sheathing material on the strain transfer performance is negligible, and the strain transfer mechanism of the strain-transfer cable is deduced on the basis of the strain transfer theory of the surface bonded fiber Bragg grating (FBG). The expression of strain transfer coefficient is obtained, and the two methods of fixed point placement and full pasting are simulated in finite element software. The corresponding strain transfer coefficient curves are obtained respectively. The research results in this paper provide a certain method and guidance for the selection of optical fiber cables in different applications in engineering applications, which is expected to promote the further optimization of the performance of distributed optical fiber sensing systems.
【学位授予单位】:电子科技大学
【学位级别】:硕士
【学位授予年份】:2014
【分类号】:TN818
,
本文编号:1661952
本文链接:https://www.wllwen.com/kejilunwen/wltx/1661952.html