车载排放测试技术的研究

A study of portable emission measurement system

对定量评价机动车在特定运行状况下排放状况的问题,研制一种车载排放测试系统,该系统由排放分析仪、GPS、尾气流量计和便携式电脑等组成,可实现对汽车在实际道路行驶时的瞬时车速及HC、CO、NO等有害气体瞬时排放因子的测量与计算。车载道路实验结果表明:汽车冷起动阶段CO、HC、NOx排放较高,而怠速阶段质量排放浓度较低;汽车加速和减速交替阶段,HC和CO排放较高;在车速较高阶段,NOx排放较高。

In order to accurately reflect the vehicle emissions change with operation condition ,the PEMS （Portable Emission Measurement System ） Is developed , which consists of emission analyzer , GPS , exhaust flow meter and mobile computer etc ,and the PEMS can measure and calculate the instantaneous speed and emission characteristics of HC ,CO ,NO .The on‐board experiment results show that ,the emission of HC ,CO ,NOx is higher at cold start stage ,while mass emission concentration is lower at idle ;HC and CO are higher at the inflection point of speed ;the NOx emission increases at the higher speed .