摘要
当前飞机货舱烟雾探测报警装置易受环境中灰尘、水蒸气等干扰源影响,导致误报率较高。为解决上述问题,提出了基于消光系数比的三波长火灾烟雾探测模型。该模型基于朗伯-比尔吸收定律,利用不同气溶胶对不同波段光的吸收差异,通过测量不同烟雾颗粒在不同波段下的光功率,构建以消光系数比(Extinction Coefficient Ratio,ECR)为核心的火灾烟雾探测模型,通过筛选相对标准差(Relative Standard Deviation,RSD)小于5%的消光系数比数据,建立火灾烟雾与干扰源的判别体系,提高火灾烟雾区分精度。开展棉绳、榉木、纸片的阴燃试验,以及正庚烷、柴油、聚氨酯的明火试验,并以细水雾和石蜡油烟雾作为干扰源进行火灾模拟试验。结果表明,不同类型的烟雾气溶胶在消光系数比上存在显著差异。当消光系数比R635 nm/532 nm介于0.70~0.89时,可以判定为石蜡油干扰源。当消光系数比R532 nm/450 nm在1.15~1.68时,则为细水雾干扰源。当消光系数比R_(635 nm/450 nm)大于1.42时,可判定为明火烟雾,消光系数比R_(635 nm/450 nm)小于1.12时可以判断为阴燃烟雾,结合具体消光系数比R_(635 nm/450 nm),可进一步区分明火与阴燃烟雾的具体类型。
This paper introduces a three-wavelength fire smoke detection model that utilizes extinction coefficient ratios.The primary objective is to reduce the high false alarm rate in aircraft cargo hold smoke detection systems,which is often exacerbated by interference from dust,water vapor,and other contaminants.By comparing the optical properties of fire smoke particles with those of interfering aerosols,a specialized three-wavelength fire smoke detection platform was developed and tested in a simulated aircraft cargo hold at the Sichuan Provincial Key Laboratory of Civil Aircraft Fire Science and Safety Engineering.Comprehensive tests were performed on smoldering fires,open-flame fires,and various interference sources,with each scenario replicated three times for accuracy.The extinction coefficient ratio across the red,green,and blue light bands was chosen as the key fire characteristic parameter.Utilizing the Lambert-Beer absorption law,we analyzed differential light absorption across these bands by various aerosols,alongside variations in extinction efficiency factors based on size parameters under Mie scattering theory.This theory posits that small smoke particles exhibit decreasing extinction efficiency as the incident wavelength increases,while larger interference particles approach an extinction efficiency of 2.To facilitate detection,a characteristic parameter library centered on extinction coefficient ratios was developed.By measuring the optical power attenuation of smoke particles across the three light bands,we established a feature parameter library focused on these ratios.We selected values with relative standard deviations below 5%to create a comprehensive database of ratio relationships,enabling effective differentiation between fire smoke particles and interfering aerosols.Four primary conclusions emerged from the experiments:(1)Smoldering smoke particle characteristics:The diameter of smoldering smoke particles is relatively small and approaches the wavelength of the incident light used in this study.Consequently,the extinction efficiency factor,which reflects the relative strength of long-wavelength versus short-wavelength absorption in smoke particles,decreases as the wavelength increases.In contrast,aerosol particles from interference sources are significantly larger than the incident light's wavelength.For these particles,the extinction efficiency factor approaches 2 and remains stable,leading to a higher extinction coefficient ratio(R_(635 nm/450 nm))for interference source aerosols compared to smoldering smoke particles.(2)Open-flame smoke properties:Open-flame smoke is characterized by incompletely combusted carbon black particles that primarily absorb light.This results in an extinction coefficient ratio that differs markedly from those of smoldering smoke and interference source aerosols,facilitating the elimination of open-flame interference in initial assessments.Subsequent analysis of the extinction coefficient ratios allows for distinguishing between smoldering smoke and interference aerosols.Each test group was replicated three times,and the implementation of a discrimination system based on extinction coefficient ratio values with a Relative Standard Deviation(RSD)of less than 5%proved effective in enhancing differentiation accuracy.(3)Identification of interference sources and fire types:By analyzing extinction coefficient ratios across three distinct wavelengths(635 nm,532 nm,and 450 nm),it is possible to identify various interference sources,open flames,and smoldering fires.Specifically,when the ratio of extinction coefficients at 635 nm and 532 nm falls between 0.70 and 0.89,paraffin oil is identified as the interference source.If the R 532 nm/450 nm extinction coefficient ratio ranges from 1.15 to 1.68,a fine water mist is indicated as the interference source.By combining specific extinction coefficient ratios,interference sources like fine water mist and paraffin oil can be initially ruled out,followed by differentiation between open flame and smoldering smoke types.An R_(635 nm/450 nm) exceeding 1.42 suggests open-flame smoke,while a value below 1.12 indicates smoldering smoke.This specific ratio can then be utilized to ascertain whether the smoke originates from a smoldering or open flame.(4)Limitations and Future Optimizations:This study was conducted under standard ambient conditions(i.e.,room temperature and pressure)and did not account for extreme environments,such as low pressure(e.g.,60 kPa)or low temperatures found in aircraft cargo holds.Additionally,the long-term stability of the detector during continuous operation has yet to be verified.Further optimization of the model based on actual cargo hold conditions is necessary.
作者
王海斌
卜宗豪
汪璐瑶
李金浩
刘全义
WANG Haibin;BO Zonghao;WANG Luyao;LI Jinhao;LIU Quanyi(College of Civil Aviation Safety and Engineering,Civil Aviation Flight University of China,Guanghan 618300,Sichuan,China;Sichuan Provincial Key Laboratory of Civil Aircraft Fire Science and Safety Engineering,Guanghan 618300,Sichuan,China;Air Traffic Control Centre,Civil Aviation Flight University of China,Guanghan 618300,Sichuan,China)
出处
《安全与环境学报》
北大核心
2026年第2期559-567,共9页
Journal of Safety and Environment
基金
国家重点研发项目(2024YFC3014400)
四川省重点实验室项目(MZ2022JB01,MZ2024JB02)。
关键词
安全工程
飞机货舱
烟雾探测
朗伯-比尔吸收
消光系数比
误报率
safety engineering
aircraft cargo hold
smoke detection
Lambert-Beer absorption
extinction coefficient ratio
false alarm rate
