燃油喷射正时对直喷式天然气发动机性能的影响(英文)  

Influence of Fuel Injection Timing on Combustion and Emission in Direct Injection Natural Gas Engine

作　　者：黄佐华[1] 曾科[1] 王子延[1] 杨中乐[1] 

机构地区：[1]西安交通大学汽车工程系,陕西西安710049

出　　处：《内燃机学报》2001年第5期417-424,共8页Transactions of Csice

基　　金：国家自然科学基金杰出青年基金资助项目 (5992 561 7)

摘　　要：使用快速压缩装置研究了燃油喷射正时对直喷式天然气发动机性能的影响。研究结果表明 ,提早喷射(喷射正时 6 0 ms)会降低燃烧初期放热速率而增加后期放热速率 ;推迟喷射 (喷射正时 75 ms)会增加燃烧初期放热速率而降低后期放热速率 ;在喷射持续期结束时 (喷射正时 80 ms)点火放热持续期最短 ;提早喷射增加火焰发展期而推迟喷射会增加后燃期 ;在当量比相同且大于 0 .8的条件下 ,提早喷射会产生相对量低的CO,而推迟喷射会产生相对量高的 CO;在当量比为 0 .6～ 0 .8时 ,不同喷射正时条件下 NOx 均较高 ,喷射推迟 NOx 降低 ;在当量比为 0 .5～ 0 .8时 ,燃烧效率较高 ,当量比小于 0 .5或大于 0 .Investigation of fuel injection timing on combustion and emission of direct injection natural gas engine is carried out using a rapid compression machine.The results show that early injection (injection timing at 60 ms) brings to slow initial heat release rate and rapid late heat release process.Late injection (injection timing at 75 ms) give rapid initial heat release rate and slow late release rate.The heat release process lasts the shortest duration when the end of fuel injection is set at 80 ms (the same timing of ignition).The shortest combustion duration occurs in the case of injection end at 80 ms.Early injection has long flame developing period whereas late injection has long late burning period.Early injection produces relative low CO while late injection produces relative high CO when equivalence ratio is larger than 0.8.NO x reaches its peak value in the range of equivalence ratio between 0.6 and 0.8 regardless of fuel injection timings.Late injection gives relatively low NO x emission.Combustion efficiency maintains high value in the range of equivalence ratio from 0.5 to 0.8,combustion efficiency decreases for both φ>0.5 and φ>0.8.

关 键 词：喷射定时 燃烧 直喷式发动机 天然气发动机 性能 快速压缩装置 燃油喷射 汽车 

分 类 号：U464.174[机械工程—车辆工程]