CAJ | 학술논문

综合运用棱镜气室与谐波检测技术,构建了适用于宽广浓度范围内的光纤甲烷检测系统.以大气环境为背景,基于比尔-朗伯(Beer-Lambert)定律在气体弱吸收时的近似表述,利用背景扣除和比值处理技术,实现了常压下甲烷不同浓度水平(0～20%)的检测.利用渐变折射率透镜(GRIN)气室测量了甲烷在不同浓度时的直接吸收谱,结合现有DFB-LD光源选择甲烷2v3带的R5支(1 648.212 nm)作为被测吸收峰.在不同浓度气体配置过程中,进行了系统的在线实验,结果表明系统示值与浓度变化间线性良好,而且系统的稳定性和动态响应特性比较理想.该系统可根据不同现场环境的甲烷浓度水平,选择适当强度的吸收线,通过步进电机调节棱镜中线间的距离,进而改变气室内有效吸收光程,拓展了仪器的应用领域,可作为煤矿巷道或天然气管道沿线的瓦斯监测仪器.
종합운용릉경기실여해파검측기술,구건료괄용우관엄농도범위내적광섬갑완검측계통.이대기배경위배경,기우비이-랑백(Beer-Lambert)정률재기체약흡수시적근사표술,이용배경구제화비치처리기술,실현료상압하갑완불동농도수평(0～20%)적검측.이용점변절사솔투경(GRIN)기실측량료갑완재불동농도시적직접흡수보,결합현유DFB-LD광원선택갑완2v3대적R5지(1 648.212 nm)작위피측흡수봉.재불동농도기체배치과정중,진행료계통적재선실험,결과표명계통시치여농도변화간선성량호,이차계통적은정성화동태향응특성비교이상.해계통가근거불동현장배경적갑완농도수평,선택괄당강도적흡수선,통과보진전궤조절릉경중선간적거리,진이개변기실내유효흡수광정,탁전료의기적응용영역,가작위매광항도혹천연기관도연선적와사감측의기.
A novel fiber methane detection system was constructed based on integration of prism gas eell and harmonic detection technique.The system can be applied to broad-range concentration detection.Grounded on the Beer-Lambert approximation,the detection of various concentration(0-20%)of methane was completed using subtraction of background and ratio processing method,as the atmosphere surroundings was treated as background.The direct absorption spectra for various concentration were measured using GRlN gas cell,combined with available DFB-LD,and the R5 line of the 2v3 band of methaRe was selected as absorption peak-The system was tested online during gas mixing process and the linear relation between system indication and concentration variation was validated,while the stability and dynamic response characteristics was confirmed by experiments.The system sensitivity can be adjusted according to the concentration level of various field environments by changing the prism distance using step motor.So that,the system can be applied to various application fields and carl be adopted as a monitoring instrument for coalmine tunnel and natural gas pipeline.