基于修正Gaussian Puff模型的飞机LTO循环PM_(2.5)排放及扩散特性研究

Research on PM_(2.5) emission and diffusion characteristics of aircraft LTO cycle based on modified Gaussian Puff model

为评估飞机细颗粒物(PM_(2.5))排放对机场周边环境的影响,构建了飞机起飞着陆(LTO)循环排放及扩散特性评估模型.首先基于机载QAR数据中的空燃比、燃烧室入口温度等热力学参数,采用一阶近似-形成氧化法的耦合模型(FOA-FOX)对细颗粒物排放特性进行评估;然后建立飞机LTO循环坐标系,结合航空器运行特征对Gaussian Puff模型进行修正,将实时排放强度及气象数据作为输入源,计算LTO循环不同时刻下的扩散浓度分布,分析影响扩散浓度的因素;最后结合计算结果,对上海浦东国际机场进行污染物监测点的布局.结果表明:LTO循环的PM_(2.5)排放强度约为38.61~845.78 mg·s^(-1),进近和起飞爬升阶段高于滑行阶段;进近后期、滑行阶段及起飞初期的扩散浓度对人群影响较大,下风向4000 m几乎不构成污染;风速增加、大气稳定度降低会不同程度地增大扩散速率.

In order to evaluate the impact of aircraft fine particulate matter(PM_(2.5))emissions on the airport surrounding environment,an aircraft LTO cycle emission and diffusion characteristics evaluation model was constructed.Firstly,based on the air-fuel ratio,combustion chamber inlet temperature and other thermodynamic parameters in the aircraft QAR data,the first-order approximation formation and oxidation method(FOA-FOX)coupling model was used to evaluate the emission characteristics of fine particles;then the aircraft LTO cycle coordinate system was established,the Gaussian Puff model was revised in combination with aircraft operating characteristics,real-time emission intensity and meteorological data were used as input sources,the diffusion concentration distribution at different times of LTO cycle was calculated,and the factors affecting diffusion concentration were analyzed.Finally,based on the calculation results,the layout of pollutant monitoring points at Shanghai Pudong International Airport was carried out.The results show that the PM_(2.5) emission intensity of LTO cycle is about 38.61~845.78 mg·s^(-1),the approach and take-off-climb phase is higher than taxi phase;the diffusion concentration level in the late approach,taxi and early take-off has a great impact on the population,while 4000m downwind almost does not constitute pollution;increasing wind speed and decreasing atmospheric stability will increase the diffusion rate to varying degrees.