N_2和CO_2稀释对天然气发动机燃烧和NO_x排放的影响  

Effects of N_2 and CO_2 dilution on the combustion and NOxemissions of natural gas engines

作　　者：李伟峰[1] 刘忠长[1] 王忠恕[1] 许允[1] 王建堃[1] 

机构地区：[1]吉林大学汽车仿真与控制国家重点实验室,长春130022

出　　处：《吉林大学学报（工学版）》2015年第4期1115-1123,共9页Journal of Jilin University:Engineering and Technology Edition

基　　金：'973'国家重大基础研究发展计划项目(2013CB228402);国家自然科学基金项目(50906033);吉林省科技发展计划项目(20126009);吉林大学研究生创新基金项目(2015092)

摘　　要：为改善天然气发动机be-NOx'此消彼长'的变化关系,以一台六缸天然气发动机为试验对象,在1450r/min、50%负荷下,保持转速、点火时刻、节气门开度、燃料量等不变,研究了N2和CO2稀释对燃烧和NOx排放的影响。结果表明:与CO2稀释相比,N2稀释能有效改善be-NOx'此消彼长'的变化关系。N2稀释抑制NOx生成的主要因素是其稀释效应;而CO2稀释抑制NOx生成的主要因素是其热效应。当稀释比或NOx排放相同时,与CO2稀释相比,采用N2稀释时混合气的燃烧速率较快,因而可获得较高的燃料经济性。To improve the ＂trade-off＂ relationship between be and NOx emissions, the effect of N2 and CO2 dilution on combustion and NOx emissions was experimentally investigated. The experiments were arranged on a six-cylinder Natural Gas （NG） engine under 1450 rpm and 50% load while keeping other conditions unchanged, e.g. the engine speed, spark timing, throttle opening and fuel amount are constants. The results show that, compared with CO2 dilution, N2 dilution can improve the ＂trade-off＂ relationship between be and NOx emissions when NOx emissions are reduced to the same levels. The main factor decreasing the NOx emissions is the dilution effect for N2 dilution and the thermal effect for CO2 dilution, respectively. Compared with CO2 dilution, the combustion rate of NG-air mixture is faster when using N2 dilution, which improves the fuel economy at the same NOx emissions or dilution ratio.

关 键 词：动力机械工程 天然气发动机 N2稀释 CO2稀释 NOX排放 燃料消耗率 

分 类 号：TK464[动力工程及工程热物理—动力机械及工程]