激光吸收光谱气体检测中谱线的自动筛选

Automatic selection of spectra lines for laser absorption spectroscopy gas detection

激光吸收光谱(LAS)技术进行气体检测具有高选择性、高灵敏度、快速响应、可多组分多参量同时非接触测量等优势,被广泛用于环境监测、污染排放检测、工业过程控制等领域。在应用LAS技术进行气体检测时,首要工作就是选择合适的目标谱线。目前对谱线的筛选都是基于人工观察完成,费时费力,效率低下。设计了一款自动化谱线筛选软件,对于给定波段范围,基于LAS检测原理和谱线筛选原则,结合测量的环境条件对HITRAN光谱数据库中的相关谱线数据进行分析,根据吸光度和谱线的线宽等对灵敏度和谱线干扰进行判断,最终输出筛选的目标谱线或测温谱线对。该方法大大提高了谱线的筛选效率,可用于LAS气体检测之前目标谱线的自动化筛选,对于气体的浓度检测和温度测量具有重要意义。

Laser absorption spectroscopy(LAS)technology has advantages of good selectivity,high sensitivity,fast response,capability of noncontact measurement of multi-species and multi-parameters in gas detection applications.Therefore,it has been widely used for environmental monitoring,pollution discharge detection,industrial process control and other fields.When LAS is applied for gas analysis,the first key step is to select suitable target spectral line for the measured gas.At present,the selection of spectral lines is based on manual work,which is time-consuming and laborious.Herein an automatic line selection software is designed.For a given band range,the relevant spectral line data in the HITRAN spectral database are analyzed based on the LAS detection principle and line selection criterion.According to the conditions of actual application scenarios,the absorbance and line width are calculated to evaluate the sensitivity and spectral line interference.And then the selected target spectral line or line pair for temperature measurement is output.This method greatly improves the efficiency of spectral line selection,which can be used for automatic screening of target spectral lines before LAS gas detection.It is of great significance for gas concentration detection and temperature measurement.