新能源汽车非排放产物生成规律及其对隧道需风量的影响研究

Study on the Generation Mechanism of Non-exhaust Emissions from New Energy Vehicles and Its Impact on Air Demands in Tunnels

随着我国新能源汽车的推广使用,隧道中的污染物组成比例发生变化。为明确新能源汽车对隧道需风量的影响,采用资料调研、理论分析等方法,量化新能源汽车的污染物生成特性及与内燃机汽车的区别,探明在坡度与车速影响下大、中、小型3类车型的新能源汽车在不同混入比情况下对隧道运营阶段需风量的影响规律,对《PIARC2019》隧道需风量计算公式进行修正,给出修正系数的计算方法,并根据工程情况给出详细的通风设计方法。研究结果为:(1)基于4种生成途径下非排放类污染物PM生成机理,给出了非排放类污染物PM生成量与汽车重量之间关系的计算公式;(2)大型、中型和小型新能源汽车的非排放颗粒基准排放量修正因子分别为1.127、1.093和1.088;(3)考虑隧道坡度、车速、混入比影响,给出了临时施工运输隧道与普通公路隧道的运营通风需风量修正系数计算方法;(4)建立了运营通风需风量计算时不修正、修正、宜设置除尘机3个层次的适用条件判别公式。

With the widespread adoption of new energy vehicles(NEVs)in China,the composition ratio of pollutants in tunnels has been changing.To clarify the impact of NEVs on air demand in tunnels,the research methods including data investigation and theoretical analysis were employed to quantify the pollutant generation characteristics of NEVs and distinguish them from internal combustion engine vehicles.The impact of different mix ratios of large,me⁃dium,and small-sized NEVs on the air demand during tunnel operation was explored under influence of the gradient and vehicle speed.The tunnel air demand calculation formula in PIARC2019 was revised,and a calculation method for the correction factor was proposed.Detailed ventilation design method was provided based on a project case.The results are as follows:(1)Based on the generation mechanisms of non-exhaust particulate matter(PM)from four sources,the calculation formulae for the relationship between non-exhaust PM emissions and vehicle weight were provided;(2)The correction factors for baseline emissions of non-exhaust PM for large,medium,and small-sized NEVs are 1.127,1.093,and 1.088,respectively;(3)Considering the impact of tunnel gradient,vehicle speed,and mix ratio,a correction factor calculation method for the air demand in temporary construction transport tunnels and ordinary road tunnels was provided;(4)The discrimination formulae for three applicability conditions—no correc⁃tion,correction,and setting dust removal machine—were established for calculating the air demand during tunnel operation.