滚流强度对可变气门升程汽油机燃油经济性影响研究  

Effects of Tumble Ratio on Fuel Economy of Variable Valve Lift Gasoline Engine

作　　者：刘洋 鲁震 冯浩 林思聪 秦博 李钰怀 LIU Yang;LU Zhen;FENG Hao;LIN Sicong;QIN Bo;LI Yuhuai(GAC Automotive Research&Development Center,Guangzhou,Guangdong,511400,China)

机构地区：[1]广州汽车集团股份有限公司汽车工程研究院,广东广州511400

出　　处：《小型内燃机与车辆技术》2022年第5期1-5,共5页Small Internal Combustion Engine and Vehicle Technique

基　　金：国家重点研发计划项目(2017YFB0103300)。

摘　　要：在一台增压直喷汽油机上开展了可变气门升程(VVL)的燃油经济性试验研究,对比不同进气升程的燃烧特性及换气过程等相关参数发现低升程方案由于米勒效应在改善泵气损失及摩擦损失方面有较明显的优势,但是燃烧速率的恶化限制了其最终燃油消耗率的改善效果。针对可变气门升程中低升程方案燃烧恶化问题进行了提高进气滚流强度对比分析,结果表明提高进气道平均滚流比能显著提升其燃油经济性。1 500 r/min平均有效压力(BMEP)0.2~1.1 MPa工况下,比油耗降幅在1.8%~4.7%之间。主要原因是低升程方案下泵气损失与燃烧速率之间存在权衡关系,而进气滚流强度的增大能够提升燃烧速率,进而突出低升程方案在降低泵气损失方面的优势,从而提高了可变气门升程方案的燃油经济性。The fuel economy of Variable Valve Lift(VVL) was experimentally researched on a turbocharged DI gasoline engine. Combustion characteristics and gas exchange process were compared at variable valve lifts and the results show that low lift has obvious advantage in reducing pumping loss and friction loss, while the deterioration of combustion limits the improvement of fuel consumption in the meantime. Based on this conclusion, increasing intake port tumble ratio was researched. The final results show that the brake specific fuel consumption(BSFC) could significantly decrease by increasing tumble ratio. BSFC decreases by 1.8%-4.7% at 1500 r/min and brake mean effective pressure(BMEP) of 0.2-1.1 MPa. The main reason is that there is a trade-off between pumping loss and combustion efficiency in low lift, while burning rate could raise by increasing tumble ratio, hence reduce VVL fuel consumption by highlighting the advantages of low lift.

关 键 词：可变气门升程 滚流强度 燃烧特性 泵气损失 

分 类 号：TK411.3[动力工程及工程热物理—动力机械及工程]