机动车尾气碳氧化物检测中的非线性修正方法  

Nonlinear correction method for vehicle exhaust carbon oxides detection

作　　者：刘国华 张玉钧[2] LIU Guohua;ZHANG Yujun(Institutes of Physical Science and Information Technology,Anhui University,Hefei 230601,China;Key Laboratory of Environment Optics and Technology,Anhui Institute of Optics and Fine Mechanics,HFIPS,Chinese Academy of Sciences,Hefei,230031,China)

机构地区：[1]安徽大学物质科学与信息技术研究院,安徽合肥230601 [2]中国科学院合肥物质科学研究院安徽光学精密机械研究所,中国科学院环境光学与技术重点实验室,安徽合肥230031

出　　处：《大气与环境光学学报》2022年第2期241-248,共8页Journal of Atmospheric and Environmental Optics

基　　金：大气环境污染监测先进技术与装备国家工程实验室开放基金,2005PP173065-2019-03。

摘　　要：机动车运行工况复杂多变,排放的尾气成分浓度范围跨度大。利用常规光学方法检测尾气中污染成分的浓度时,由于受限于光学气池的结构固定和系统对光电微弱信号的检测极限,因此待测气体的量程和精度范围都受到很大限制。基于朗博比尔定律,在待测气体浓度变量上增加指数因子修正,可以在不降低测量精度的同时,实现尾气CO、 CO_(2)大量程检测。用标准气体对便携式机动车尾气检测装置进行标定实验,结果表明,传统的线性修正方法得到的CO拟合度为0.988, CO_(2)拟合度为0.998;而增加了非线性修正因子后得到的CO拟合度为0.999, CO_(2)拟合度为0.999。进一步外场对比实验表明,修正后的仪器测量结果与同类先进仪器的一致性较好,柴油车实验拟合度为0.93,汽油车拟合度为0.95,验证了非线性修正方法的必要性和实用性。As the operating conditions of motor vehicles are complex and changeable, the concentration range of exhaust components is very large. Due to the fixed structure of optical gas cell and the detection limit of the system for weak photoelectric signal, the concentration range and detection accuracy of the gases to be measured are greatly limited when using conventional optical methods to detect the concentration of pollutants in exhaust gas. It is found that based on Lambert Beer′s law, adding an exponential factor correction to the gas concentration variable to be measured can realize the large range detection of CO and CO_(2) without reducing the measurement accuracy. The calibration experiment of the portable vehicle exhaust detecter with standard gas shows that the fitting degrees of CO and CO_(2) obtained by the traditional linear correction method are 0.988 and 0.998 respectively, while those of CO and CO_(2) obtained after adding nonlinear correction factor are 0.999 and 0.999 respectively. Further field comparison shows that the measurement results of the modified instrument are in good agreement with those of similar advanced instruments. The experimental correlation of diesel vehicle is 0.93 and that of gasoline vehicle is 0.95, which verifies the necessity and practicability of the proposed nonlinear correction method.

关 键 词：光学检测 非线性修正 机动车尾气 碳氧化物 

分 类 号：TN219[电子电信—物理电子学] X831[环境科学与工程—环境工程]