光学学报, 2015, 35 (2): 0230001, 网络出版: 2015-01-21
基于波长调制技术的温度实时测量方法研究
Study on Real-Time Temperature Measurement Based on Wavelength Modulation Technology
光谱学 温度测量 波长调制吸收光谱技术 分时锯齿 二次谐波信号 spectroscopy temperature measurement wavelength modulation absorption spectroscopy timeshare sawtooth wave second harmonic signal
摘要
可调谐二极管激光吸收光谱技术(TDLAS)以其响应速度快、灵敏度高、非接触等优点已被广泛应用于气体浓度、温度的原位在线测量。基于波长调制吸收光谱技术,理论分析和推导了二次谐波温度反演公式。并采用分时锯齿波扫描形式使两个激光器分别产生覆盖中心波长为760.21 nm 和760.88 nm 的两条氧气吸收谱线的激光,经2×1 光纤耦合器耦合为一束光束,通过测量管式炉内同一区域的二次谐波信号来反演有氧环境中的平均温度值。为了修正谱线线型和光强对实验所得的二次谐波信号峰值比值的影响,采用室温下标定温度反演公式中所需参数的方法,有效地简化了实验过程,提高了测量精度。温度在300 K~900 K 范围内变化的测量结果与管式炉的平均温度值具有较高的一致性,误差在±20 K 以内。
Abstract
Tunable diode laser absorption spectroscopy (TDLAS) has been widely used in the gas concentration and temperature online monitoring because of its excellent characteristics such as fast response, high spectral resolution and non-contact feature. In order to reduce error values and simplify experimental equipments, the temperature inversion theory and derivation formula based on wavelength modulation absorption spectroscopy are analyzed. Two distributed feed back (DFB) lasers with output wavelengths of 760.21 nm and 760.88 nm generate laser covering two oxygen absorption lines with time-sharing sawtooth scanning, respectively. Only one laser beam passes through the same optical path after coupling by a 2×1 fiber coupler. Average temperature in the tube-furnace is obtained by the peak-ratio of second harmonic signals. A method to calibrate required parameters for temperature inversion at indoor temperature is used to correct the impact of line-shape and spectral intensity. The experimental results show that the measured temperatures and the preset values within the temperature of 300 K~900 K are consistent, and the measurement error is within ±20 K.
孙鹏帅, 张志荣, 夏滑, 庞涛, 吴边, 崔小娟, 沈凤娇, 王煜, 董凤忠. 基于波长调制技术的温度实时测量方法研究[J]. 光学学报, 2015, 35(2): 0230001. Sun Pengshuai, Zhang Zhirong, Xia Hua, Pang Tao, Wu Bian, Cui Xiaojuan, Shen Fengjiao, Wang Yu, Dong Fengzhong. Study on Real-Time Temperature Measurement Based on Wavelength Modulation Technology[J]. Acta Optica Sinica, 2015, 35(2): 0230001.