二冲程缸内直喷发动机燃烧室设计  

Combustion Chamber Design of Two-Stroke GDI Engine

作　　者：牛燕华[1] 魏民祥[1] 吴伟建 季昊成[1] 

机构地区：[1]南京航空航天大学能源与动力学院,南京210016 [2]中山陵园管理局办公室,南京210000

出　　处：《重庆理工大学学报（自然科学）》2017年第4期64-75,共12页Journal of Chongqing University of Technology：Natural Science

基　　金：江苏省研究生科研创新基金资助项目(KYLX15-0262)

摘　　要：采用三维实体建模软件UG对某二冲程发动机的燃烧室进行直喷化设计,并利用三维CFD仿真软件Fluent对直喷燃烧室的缸内流场和混合气形成进行CFD仿真与分析,仿真计算从发动机上止点(0°CA)开始计算。分析结果表明:锥形燃烧室扫气效率较低,在燃烧室顶部的废气残余较高,偏置和完全对称的拱形燃烧室扫气效率相近,由于废气堆积较集中,不利于燃烧的传播;选择完全对称的拱形燃烧室来研究喷油正时对混合气形成的影响,在转速1 600 r/min、节气门开度10%的工况下,喷油正时在70°~90°CA,BTDC可以在火花塞附近形成较浓混合气,远离火花塞形成较稀的混合气;在转速5 000 r/min、节气门开度100%的工况下,喷油正时在200°~220°CA,ATDC可以形成较均匀的混合气。Using three-dimensional solid modeling software UG, the two stroke GDI engine＇s combustion chamber was carried out, and using the three-dimensional CFD simulation software Fluent, the flow field and mixture formation of the GDI combustion chamber were simulated and analyzed. Taking the top dead center （0- CA） as the simulation beginning, the results show that： the scavenging efficiency of the tapered chamber is low, and the exhaust gas residual at the top of thecombustion chamber is higher, but as the bias combustion exhaust gas accumulation, it is conductive to the spread of combustion ; and the effect of injection timing on the mixture formation was studied on the completely symmetrical arch chamber, and at the speed of 1 000 r/min, the throttle position 10% condition, and when the injection timing from 70°CA to 90°CA, rich mixture can be formed near the spark plug and thin mixture can be formed away from spark plug; At the speed of 6 000 r/min, throttle position 100% mixture can be formed condition, and when in the cylinder. injection timing 200°CA to 220°CA, a homogeneous

关 键 词：燃烧室 缸内流场 喷油定时 分层混合气 均质混合气 

分 类 号：V234[航空宇航科学与技术—航空宇航推进理论与工程]