基于双光路的镜头污染度检测在颗粒物浓度测量中的研究  

Research on Particle Concentration Measurement Based on Dual Light Path Lens Pollution Detection

作　　者：焦敏 JIAO Min(State Key Laboratory of Gas Disaster Detecting,Preventing and Emergency Controlling,Chongqing 400037,China;China Coal Technology and Engineering Group Chongqing Research Institute,Chongqing 400037,China)

机构地区：[1]瓦斯灾害监控与应急技术国家重点实验室,重庆400037 [2]中煤科工集团重庆研究院有限公司,重庆400037

出　　处：《仪表技术与传感器》2021年第7期122-126,共5页Instrument Technique and Sensor

基　　金：国家重点研发计划资助项目(2016YFF0102800)。

摘　　要：为了解决光散射法颗粒物浓度在线监测系统中激光检测镜头容易受到污染的问题,设计了具有光学镜头污染度自检功能的双光路颗粒物浓度检测系统,对不同污染度光学镜头的散射光信号强度进行实验测量,结合米散射理论的颗粒物浓度计算,得到光学镜头污染程度与激光检测信号衰减的关系。结果表明,随着激光检测镜头污染程度的加重,光散射法测量的颗粒物浓度值会出现严重的负偏差,双光路颗粒物浓度检测系统能够用于光学镜头污染度检测,通过光学镜头污染度的实时测量,可计算出光学镜头由于污染而造成的光信号衰减度,光学镜头污染程度达到25%时,修正后的颗粒物浓度测量误差≤11.92%。In order to solve the problem that the laser detection lens are easy to be contaminated in the on-line monitoring system of particle concentration by light scattering method,a dual optical path particle concentration detection system with self inspection function of optical lens pollution degree was designed,and the scattering light signal intensity of optical lens with different pollution degree was measured experimentally.The particle concentration was calculated based on the Mie scattering theory.The relationship between the contamination degree of optical lens and the attenuation of laser detection signal was obtained.The results show that with the aggravation of laser detection lens pollution,the particle concentration value measured by light scattering method will appear serious negative deviation.The particle concentration detection system with double optical paths can be used to detect the pollution degree of optical lens.Through the real-time measurement of the pollution degree of optical lens,the attenuation degree of optical signal and the pollution degree of optical lens can be calculated when it reaches 25%,the corrected measurement error of particulate matter concentration is no more than 11.92%.

关 键 词：双光路 污染度 颗粒物检测 光散射 信号衰减 光学探头 

分 类 号：X851[环境科学与工程—环境工程]