CNG重型车排气含水量对CO_(2)测量的影响  

Effect of exhaust water content of a CNG heavy-duty vehicle on CO_(2)measurement

作　　者：钟祥麟 李彤 黄鹏程 孟庆梁 ZHONG Xianglin;LI Tong;HUANG Pengcheng;MENG Qingliang(CATARC Automotive Test Center(Tianjin)Co.,Ltd.,Tianjin 300300,China)

机构地区：[1]中汽研汽车检验中心(天津)有限公司,天津300300

出　　处：《内燃机与动力装置》2024年第4期41-47,55,共8页Internal Combustion Engine & Powerplant

摘　　要：为研究不同干湿基修正方法对压缩天然气(compressed natural gas,CNG)重型车冷起动阶段CO_(2)排放测量结果的影响,在底盘测功机上对某国六CNG车辆进行不同试验循环下冷起动测试,分别采用国六标准中推荐的干湿基修正法和排气中水的体积分数湿基修正法计算车辆冷起动阶段的CO_(2)排放。结果表明:车辆冷起动阶段,采用国六标准推荐的干湿基修正法计算的CO_(2)排放结果偏差较大;充分热机后,2种方法的计算结果趋于一致;采用国六推荐方法修正时,相比直接湿基测量结果,冷起动热机阶段的排放中CO_(2)体积分数偏低约14%。对于排气中水的体积分数较大的燃用CNG、甲醇、汽油等燃料的车辆的冷起动阶段CO_(2)排放计算,采用排气中水的体积分数计算CO_(2)湿基修正因子,结果更准确。To investigate the influence of different dry-wet correction methods on the measurement results of CO_(2)emissions during the cold start phase of a compressed natural gas(CNG)heavy-duty vehicle,cold start tests are conducted on a CHINA 6 CNG vehicle under different test cycles using a chassis dynamometer.The CO_(2)emissions during the cold start phase of the vehicle are calculated using the dry-wet correction method recommended by CHINA 6 regulations and the dry-based correction method based on the volume fraction of H_(2)O in the exhaust gas.The results indicate that during the cold start phase of vehicles,the CO_(2)emissions calculated using the dry-wet correction method recommended by CHINA 6 have a significant deviation.After sufficient heating,the calculation results of the two methods tend to be consistent.When using the recommended method of China 6 for correction,compared to direct wet-based measurement results,the CO_(2)emissions during the cold start are about 14%lower.For the calculation of CO_(2)emissions during the cold start phase of CNG,methanol,gasoline and other vehicles with high exhaust water content,using the volume fraction of H_(2)O in the exhaust to calculate the CO_(2)dry-wet correction factor yields more accurate results.

关 键 词：CNG 重型车 冷起动 干湿基修正 

分 类 号：X734.2[环境科学与工程—环境工程] U491.92[交通运输工程—交通运输规划与管理]