共查询到20条相似文献,搜索用时 31 毫秒
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双套管式光纤Bragg光栅温度传感器 总被引:3,自引:0,他引:3
研制了一种双套管式光纤Bragg光栅温度传感器,以实现无外力作用的温度测量。其中外套管隔离外加应力应变,在内套管内松弛地放置光栅以隔离封装结构的表观热应变。引入引出尾纤穿过带孔螺栓,以探测多个串联光栅。为了避免光栅处于张拉状态,封装在外套管1、外套管2和内套管中的光纤余长应分别大于1.4mm,1.8mm和0.4mm。试验结果表明,该光栅传感器的温度响应灵敏度为9.671×10-3nm/℃,温度测量分辨率为0.1℃。当水温从20℃跃变到70℃时,该传感器的温度响应时间分别为t0.5=15±2s和t0.9=52±4s。当水温从70℃跃变到20℃时,该传感器的温度响应时间分别为t0.5=26±9s和t0.9=63±8s。 相似文献
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光纤Bragg光栅应变、温度交叉敏感问题解决方案 总被引:6,自引:2,他引:6
应变和温度变化都会引起光纤Bragg光栅(FBG)反射波长的移动,这种交叉敏感问题是制约FBG传感检测技术实用化的“瓶颈”。从应变、温度交叉敏感的物理机制出发,分两类综述国内外关于交叉敏感问题的解决方案,介绍各类方案的工作原理,并详细分析几种近年来出现的典型方案的优缺点。 相似文献
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光纤布喇格光栅应变传感器结构优化研究 总被引:1,自引:2,他引:1
提出了一种改进的光纤光栅应变传感器结构,用有限元分析软件对其进行建模和静力仿真,得到其应力分布和光栅区域的应变情况.在整体宽度与厚度相等的情况下,此结构的灵敏度约为传统"工"字型结构的600倍.进一步分析了其关键区域的6个结构参量对应变灵敏度及量程的影响.筛选、设计并加工出不同尺寸的两种应变片,分别用UV胶与玻璃焊料对光栅进行封装,得到灵敏度分别为:249pm/N、330pm/N和1.1pm/N.比较分析表明,本文提供的分析方法与数据,可为不同工程应用场合的最优结构设计提供依据. 相似文献
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A novel stable multi-wavelength fiber Bragg grating laser is achieved and its sensing characteristic with the strain is studied. The beat signals generated by the multi-wavelength fiber laser are measured under different strains. Four-wave mixing (FWM) is firstly observed in such a short-cavity fiber laser. 相似文献
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A study on fiber Bragg grating (FBG) strain sensor, based on erbium-doped fiber (EDF) laser, is presented. A strain-sensing element, FBG, also acts as the lasing wavelength selecting component. When strain is applied on the FBG, the laser cavity loss changes, leading to a modification of the laser transient. Strain measurements are obtained in the time domain by simply measuring the EDF laser build-up time. Relative variation in the build-up time of up to 190%, for a strain range from 0 με to 2350 με, is achieved with a resolution corresponding to a strain of better than 2.35 με. This study demonstrates a novel fiber sensor concept and the technical feasibility to develop fiber strain measurement. 相似文献
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针对光纤布拉格光栅(FBG)温度和应变的交叉敏感问题,设计了一种带熔点保偏光纤光栅(PMFBG)结构。该结构通过将2段保偏光纤带加大推进量熔接,形成中间凸起结构,然后在熔点位置写入光栅。文中首先采用熊猫保偏光纤设计制作了该结构,并搭建实验装置测试其在(0~2)N轴向应力作用下的反射光谱,发现PMFBG快轴和慢轴的反射谱均分裂成2个峰值,随着轴向应力的增加,反射谱整体产生红移,同时分裂的2个峰值强度的比值单调减小,且不受温度的影响。随后,采用有限元法分析了该结构的轴向应变分布,并基于传输矩阵法仿真分析了该PMFBG反射光谱随应力的变化特性,仿真与实验结果的一致性较好。证实可利用PMFBG反射光谱的峰值之比消除轴向应变与温度的交叉敏感性,实现轴向应变的测量。 相似文献
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为解决干涉型光纤应变传感器自由光谱范围较小或干涉条纹精细度较低等问题,提出了一种基于单拉锥光纤布拉格光栅的法布里-珀罗腔的应变传感结构及其改进方案。利用啁啾光纤布拉格光栅不同位置反射不同波长的特性,形成腔长随波长连续变化的法布里-珀罗腔,得到了无穷大的自由光谱范围且谐振谷精细度高。数值计算结果表明,应变传感灵敏度与拉锥光纤的腰区直径和栅区长度正相关。在0~300 με范围内,当腰区直径为光纤直径的3/25,栅区长度为30 mm时,应变传感灵敏度为7.05 pm/με。该结果对其他干涉型传感结构的设计具有一定的参考价值。 相似文献
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A novel fiber-laser-based strain sensor is proposed and experimentally demonstrated. The laser cavity is composed of a high-birefringence Sagnac fiber loop mirror (HiBi-SFLM) and a fiber Bragg grating (FBG) which also acts as a strain-sensing element. In the linear region of the HiBi-SFLM reflection spectrum, when the strain applied on the FBG makes the Bragg grating wavelength shift, the laser output power changes due to refleetivity variation of the HiBi-SFLM. Experimental results show that the laser output power varies almost linearly with the applied strain. The measurement of the output power can be performed by a conventional photo-detector. 相似文献
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A high sensitive fiber Bragg grating (FBG) strain sensor with automatic temperature compensation is demonstrated. FBG is axially linked with a stick and their free ends are fixed to the measured object. When the measured strain changes, the stick does not change in length, but the FBG does. When the temperature changes, the stick changes in length to pull the FBG to realize temperature compensation. In experiments, 1.45 times strain sensitivity of bare FBG with temperature compensation of less than 0.1 nm Bragg wavelength drift over 100 ℃ shift is achieved. 相似文献
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A four-element fiber Bragg grating acceleration sensor array is presented in this paper. The system combines an unbalanced Mach–Zehnder interferometer and three coarse wavelength division multiplexers (WDMs). The totally passive scheme has the advantages of high operation frequency and loose requirements for the working environment. An acceleration resolution of better than for the four channels is achieved. 相似文献
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A novel fiber Bragg grating high-temperature sensor 总被引:3,自引:0,他引:3
A novel fiber Bragg grating (FBG) sensor for the measurement of high temperature is proposed and experimentally demonstrated. The interrogation system of the sensor system is simple, low cost but effective. The sensor head is comprised of one FBG and two metal rods. The lengths of the rods are different from each other. The coefficients of thermal expansion of the rods are also different from each other. The FBG will be strained by the sensor head when the temperature to be measured changes. The temperature is measured basis of the wavelength shifts of the FBG induced by strain. A dynamic range of 0–800 °C and a resolution of 1 °C have been obtained by the sensor system. The experiment results agree with theoretical analyses. 相似文献