Chen Chen, Gao Song, Chen Liang, Bao Xiaoyi
Department of Physics, University of Ottawa, 25 Templeton Street, Ottawa, ON K1N 6N5, Canada.
Sensors (Basel). 2020 Nov 10;20(22):6407. doi: 10.3390/s20226407.
The distributed high temperature measurement of an optical fiber subjected to electric arc discharges based on optical frequency-domain reflectometry is experimentally demonstrated. The distributed temperature profile is attained in an open glow regime of a few milliamps with maximum detectable temperature up to 2100 ± 20 °C. The discharge arc-induced softened length of the fiber and mechanical stress are measured and statistically analyzed in terms of the correlation of the Rayleigh spectra. The large wavelength scanning range of OFDR enables much higher accuracy for the delay time measurement with a minimum measured delay of 40 fs. The delay shift over the entire heating range for a single discharge duration is statistically calculated by using a temporal correlation method. The reliability of the thermal sensitivity coefficient as 10 pm/°C for telecom single mode fiber (SMF, @1550 nm) is quantitatively analyzed and evaluated by the correlation coefficient. Lastly, a spectral mapping method is employed in spectrum monitoring for discharge dynamic impact on the optical path length (OPL) and local Rayleigh scatter.
基于光频域反射法对承受电弧放电的光纤进行分布式高温测量的实验得到了验证。在几毫安的开放辉光状态下获得了分布式温度分布，最大可检测温度高达2100±20°C。根据瑞利光谱的相关性，测量并统计分析了放电电弧引起的光纤软化长度和机械应力。光频域反射仪（OFDR）的大波长扫描范围使得延迟时间测量具有更高的精度，最小测量延迟为40飞秒。通过使用时间相关方法，统计计算了单个放电持续时间在整个加热范围内的延迟偏移。通过相关系数对电信单模光纤（SMF，@1550nm）热灵敏度系数为10pm/°C的可靠性进行了定量分析和评估。最后，采用光谱映射方法进行光谱监测，以研究放电对光程长度（OPL）和局部瑞利散射的动态影响。
