公路坡度差对车辆尾气排放的影响分析

公路的几何线形设计直接影响机动车的尾气排放。为了探究凸形竖曲线路段前后坡差变化对小客车尾气排放的影响，以速度预测模型和多项式模型为基础，得到了凸形竖曲线路段不同坡差的逐秒速度曲线，统计分析不同线形组合条件下机动车比功率分布，基于综合移动源排放预测模型MOVES，得到不同坡差情况下凸形竖曲线路段尾气排放量。结合SPSS软件进行小客车单位竖曲线长度上CO2排放量与坡差进行拟合，得到单位距离小客车CO2排放量与坡差的关系，最后通过实测试验对模拟结果进行验证。结果表明，小客车在凸形竖曲线上行驶，前后坡度差代数值越大，尾气排放量越多。在四种主要排放物中，CO2排放量最大，依次是CO、NOx、NH3排放量。研究结果对提高低碳公路设计水平具有一定的参考作用。

Analysis on the Influence of Highway Slope Difference on Vehicle Exhaust Emission

The geometric linear design of the curve directly affects vehicle exhaust emissions. In order to explore the influence of the front and rear slope difference of the convex vertical curve section on passenger car exhaust emissions, the speed prediction model and polynomial model are used to generate the second-by-second speed profile of the convex vertical curve section with different slope differences, and statistical analysis under different linear combinations The specific power distribution of motor vehicles is based on the MOVES model, and the exhaust emissions of the convex vertical curve section under different slope differences are obtained. The SPSS software is used to fit the CO2 emissions per unit vertical curve length of the passenger car with the slope difference, and the relationship between the CO2 emissions per unit distance and the slope difference is obtained. Finally, the simulation results are verified through actual test. The results show that when a passenger car runs on a convex vertical curve, the greater the algebraic value of the front and rear slope difference, the more exhaust emissions. Among the four main emissions, CO2 emissions are the largest, followed by CO, NOx, and NH3 emissions. The research results have a certain reference for improving the design level of low-carbon highways.