将可调谐半导体激光吸收光谱技术应用于高温气体浓度在线检测,谱线参数的准确性非常重要.为利用红外波段进行燃烧生成H2 O的浓度在线测量,需要实验校准H2 O的谱线参数,尤其是A r加宽系数,该系数对燃烧反应速率测量和机理验证至关重要.采用半导体激光器作为光源,结合实验室搭建的谱线参数测量系统,采集了1.39μm波段附近H2 O的4条吸收谱线信号,获得了谱线线强、自加宽系数和N2加宽系数,与HITRAN数据库和文献结果进行了对比,均吻合较好.首次系统地获得了该波段谱线的Ar加宽系数.在谱线参数确定基础上,获得了在反射激波高温条件下H2/O2/A r燃烧生成H2 O的浓度随时间的演变曲线,验证了相应燃烧动力学机理.结果为利用该波段进行含氢燃料燃烧过程H2 O浓度测量及相关高温燃烧动力学研究提供了可靠的实验依据.%The accuracy of absorption spectral parameters is very important for the on-line measurement of combustion gas based on tunable diode laser absorption spectroscopy .In order to apply the spectroscopic parameters in infrared region in detecting the H2O concentration ,it is necessary to validate these parameters experimentally ,especially the Ar-broadening coefficient ,which is crucial to elementary reaction in combustion and validation mechanism .By using a distributed feed back diode laser as light source and combining with spectral parameters measurement system ,four spectral lines of H2 O around 1.39μm were collected . The line intensity ,self-broadening and N2-broadening coefficient were obtained .The results agreed well with those in HITRAN database and literature .Moreover ,the Ar-broadening coefficient was acquired systematically for the first time .By using current measured spectra parameters ,the time-history of H2 O concentration from H2/O2/Ar combustion behind high temperature reflected shock waves was obtained and corresponding combustion kinetic mechanisms were validated .The results in this work will provide reliable database for the measurement of H2 O concentration from the combustion process of hydrocarbon fuels ,as well as the validation of corresponding combustion kinetics research .
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