Development of a fast temperature sensor for combustion gases using a single tunable diode laser
Development of a fast temperature sensor for combustion gases using a single tunable diode laser
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DOI：
10.1007/s00340-005-1934-y
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发表时间：
2005-08
期刊：
影响因子：
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通讯作者：
Xin Zhou;J. Jeffries;R. Hanson
中科院分区：
文献类型：
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作者：
Xin Zhou;J. Jeffries;R. Hanson
通过系统分析1 ~ 2 μm光谱区水光谱的HITRAN模拟，确定了12对最适合单束DFB激光火焰温度测量的近红外水过渡线对。利用波长调制和2f检测的扫描波长技术，在1.4 μm附近的特定线对进行了燃烧系统气体温度的非侵入式测量。该传感器使用单二极管激光器（分布反馈），工作在1.4 μm附近，以2 kHz重复率扫描一对H2O吸收跃迁（7154.354 cm-1和7153.748 cm-1）的波长。波长被调制（f=500 kHz），调制幅度a=0.056 cm-1。气体温度由两个选定的H2O跃迁的二次谐波信号的比值推断。光纤耦合的单激光器设计使系统紧凑，坚固，低成本和易于组装。作为传感器开发工作的一部分，应用设计规则来优化谱线选择，并通过实验室测量确定所选跃迁的基本光谱参数，包括温度相关谱线强度、自展宽系数和空气展宽系数。新的传感器设计包括硬件和软件的考虑，以实现快速数据采集和分析；在大气压下的实验室火焰测量中，温度读出率为2千赫。扫描波长和波长调制的结合最大限度地减少了发射和光束转向的干扰，从而产生了一种鲁棒的温度传感器，有望用于燃烧控制应用。
The 12 best NIR water transition line pairs for temperature measurements with a single DFB laser in flames are determined by systematic analysis of the HITRAN simulation of the water spectra in the 1–2 μm spectral region. A specific line pair near 1.4 μm was targeted for non-intrusive measurements of gas temperature in combustion systems using a scanned-wavelength technique with wavelength modulation and 2f detection. This sensor uses a single diode laser (distributed-feedback), operating near 1.4 μm and is wavelength scanned over a pair of H2O absorption transitions (7154.354 cm-1& 7153.748 cm-1) at a 2 kHz repetition rate. The wavelength is modulated (f=500 kHz) with modulation amplitude a=0.056 cm-1. Gas temperature is inferred from the ratio of the second harmonic signals of the two selected H2O transitions. The fiber-coupled-single-laser design makes the system compact, rugged, low cost and simple to assemble. As part of the sensor development effort, design rules were applied to optimize the line selection, and fundamental spectroscopic parameters of the selected transitions were determined via laboratory measurements including the temperature-dependent line strength, self-broadening coefficients, and air-broadening coefficients. The new sensor design includes considerations of hardware and software to enable fast data acquisition and analysis; a temperature readout rate of 2 kHz was demonstrated for measurements in a laboratory flame at atmospheric pressure. The combination of scanned-wavelength and wavelength-modulation minimizes interference from emission and beam steering, resulting in a robust temperature sensor that is promising for combustion control applications.