燃气车废气再循环寒区潜在失效浅析  

Analysis on Potential Failure of Gas Vehicle Exhaust Gas Re-circulation in Cold Area

作　　者：袁志宏 康孝峰 马佳 YUAN Zhihong;KANG Xiaofeng;MA Jia(Institute of Automotive Engineering,Shaanxi Heavy Duty Automobile Co.,Ltd.,Xi’an 710200,China)

机构地区：[1]陕西重型汽车有限公司汽车工程研究院,陕西西安710200

出　　处：《汽车实用技术》2022年第6期43-46,共4页Automobile Applied Technology

摘　　要：国六阶段天然气发动机采用三元催化转化器和理论空燃比相结合的技术路线。与国五阶段稀薄燃烧相比,缸内热负荷和爆震显著增加,燃气消耗量也出现明显增加。为改善天然气发动机热负荷和爆震,提高燃气经济性,天然气发动机引入了废气再循环系统。天然气主要成分是甲烷,燃烧后发动机尾气中水分含量较高,在极寒环境下,废气经废气再循环系统冷却器冷却进入进气系统后,可能出现废气再循环阀、燃气混合器、节气门等部位结冰的潜在失效模式。文章介绍增加废气再循环系统后出现结冰现象的原因、车辆运行表现和寒区试验验证部件,提前识别可靠性风险,保证车辆在极寒环境下可靠运行。China’s six stage natural gas engine adopts the technical route of combining three-way catalytic converter and theoretical air-fuel ratio. Compared with the fifth stage lean combustion in China, the heat load and knock in the cylinder are significantly increased, and the fuel gas consumption is also significantly increased. In order to improve the heat load and knock of natural gas engine and improve the fuel economy, the exhaust gas re-circulation system is introduced into natural gas engine. The main component of natural gas is methane. After combustion, the moisture content in the engine exhaust is high. In extremely cold environment, after the exhaust gas is cooled by exhaust gas re-circalation(EGR) cooler and enters the intake system, there may be potential failure modes of icing in the exhaust gas re-circulation valve, gas mixer, throttle and other parts. This paper introduces the causes of icing after adding exhaust gas re-circulation system,vehicle operation performance and cold zone test verification components, so as to identify the reliability risk in advance and ensure the reliable operation of vehicles in extremely cold environment.

关 键 词：燃气车 废气再循环系统 发动机 潜在失效 

分 类 号：U464.239[机械工程—车辆工程]