低温和常温环境下EGR冷却器积碳台架试验对比研究  

Comparative Study on Bench Test of Carbon Deposits in EGR Cooler in Low-Temperature and Room Temperature Environments

作　　者：税绍强 魏厚敏[1] 田茂军[1] 邓力[1] 唐卜 唐秀云 SHUI Shaoqiang;WEI Houmin;TIAN Maojun;DENG Li;TANG Bu;TANG Xiuyun(China Automotive Engineering Research Institute Co.,Ltd.,Chongqing 401122,China)

机构地区：[1]中国汽车工程研究院股份有限公司,重庆401122

出　　处：《汽车工程学报》2023年第4期597-602,共6页Chinese Journal of Automotive Engineering

摘　　要：为研究发动机低温和常温环境下EGR冷却器积碳的差异性,以两台相同型号和配置的国Ⅵ柴油机为试验对象,设计了常温(25℃)、低温(-8℃)两种不同环境温度下EGR积碳发动机896 h台架试验。结果表明,低温环境下EGR冷却器的积碳程度和速度均大于常温,换热效率下降幅度和压力损失增大幅度均大于常温;EGR冷却器积碳导致的换热效率下降是试验后NOx、PM排放增大,HC排放减小的主要原因,冷却器换热效率下降越严重排放变化越明显;HC的冷凝会导致废气中HC浓度的下降,排气温度和冷却介质的冷却能力都对EGR管道内HC浓度的下降有影响,但是冷却介质的冷却能力起主导作用。In order to compare the carbon deposits in the EGR cooler in the room temperature and the low temperature environments respectively,two nationalⅥdiesel engines with the same model and configuration were tested.And the 896 h bench testing of the EGR engine under two different ambient temperatures(25℃and-8℃)was designed.The results show that the amount of carbon deposit,the deposition rate,the decrease in heat exchange efficiency and the increase in pressure drop in the EGR cooler at-8℃are greater than those at 25℃.The decrease in heat exchange efficiency caused by the carbon deposits in the EGR cooler leads to the increase in NOx and PM emissions and the reduction of HC-emissions after the test.The more sharply the heat exchange efficiency dropped,the more obvious the emission change was.The condensation of HC will cause a reduction in the HC concentration in the exhaust sample.Both the exhaust temperature and the capacity of the cooling medium have an effect on the HC concentration in the EGR pipe.However,the capacity of the cooling medium plays a leading role.

关 键 词：发动机 废气再循环 环境温度 台架试验 积碳 

分 类 号：TK427[动力工程及工程热物理—动力机械及工程]