高功率密度柴油机大喷油量喷雾撞壁燃烧特性研究  

Study on Large Injection Mass Spray Impingement Combustion Characteristics of High Power Density Diesel Engine

作　　者：董东升 魏明亮 隆武强[1] 王蕊[2,3] 田华 杨继雅[1] DONG Dongsheng;WEI Mingliang;LONG Wuqiang;WANG Rui;TIAN Hua;YANG Jiya(Dalian University of Technology,Dalian 116024,China;State Key Laboratory of Intelligent Agricultural Power Equipment,Luoyang 471039,China;Luoyang Tractor Research Institute Co.,Ltd.,Luoyang 471039,China)

机构地区：[1]大连理工大学能源与动力学院,辽宁大连1160241 [2]智能农业动力装备全国重点实验室,河南洛阳471039 [3]洛阳拖拉机研究所有限公司,河南洛阳471039

出　　处：《拖拉机与农用运输车》2023年第5期20-23,共4页Tractor & Farm Transporter

摘　　要：动力技术的快速发展对动力系统的功率密度的要求越来越高,其中高功率密度柴油机应用场景广泛,对于提升我国农用机械、重型工程机械等动力系统技术水平至关重要。高功率密度柴油机需要大喷油量在有限燃烧室空间内的快速燃烧,这就需要提高燃油喷射压力,大量燃油喷雾撞壁燃烧现在不可避免。采用数值模拟的方法研究了大喷油量喷雾撞壁燃烧现象:喷雾撞壁燃烧和自由喷雾燃烧特性相比,适当的喷雾撞壁距离有利于改善燃烧,撞壁距离过短,出现燃油喷雾过早撞壁现象,不利于燃油喷雾在燃烧空间的扩散,油气混合质量变差,导致燃烧恶化。喷雾撞壁也会强化喷雾和空气混合过程,45 mm的喷雾撞壁距离有利于提高燃烧速度;壁面温度升高着火时刻提前,soot生成增多,后燃严重,燃烧持续期变长,不利于燃烧效率的提升。With the rapid development of power technology,the requirements for the power density of the power system are becoming higher and higher.Among them,high-power density diesel engines are widely used and are crucial for improving the technical level of power systems in agricultural machinery,heavy engineering machinery,and other fields in China.High power density diesel engines need large fuel injection volume to burn rapidly in limited combustion chamber space,which requires increasing fuel injection pressure.Large amount of fuel spray impingement combustion is now inevitable.In this paper,numerical simulation method is used to study the spray impingement combustion phenomenon with large fuel injection volume:compared with the combustion characteristics of free spray,the proper wall impingement distance of spray is conducive to improving combustion.The wall impingement distance is too short,which leads to the premature wall impingement phenomenon of fuel spray,which is not conducive to the diffusion of fuel spray in the combustion space,and the quality of fuel air mixture becomes worse,leading to combustion deterioration.Spray impingement can also enhance the mixing process of spray and air,and 45 mm spray impingement distance is conducive to improving the combustion speed.The wall temperature directly affects the ignition time.As the wall temperature increases,the generation of soot increases,leading to severe post combustion and longer combustion duration,which is not conducive to the improvement of combustion efficiency.

关 键 词：高功率密度柴油机 大喷油量 撞壁距离 壁面温度 

分 类 号：TK42[动力工程及工程热物理—动力机械及工程]