氨能量分数和喷射策略对双燃料低速机燃烧与排放影响  

Effect of Ammonia Energy Fraction and Injection Strategy on Combustion and Emission of a Dual-Fuel Low-Speed Engine

作　　者：史歆如 熊仟 潘聪懿 刘龙[1] 傅师翊 赵建辉[1] Shi Xinru;Xiong Qian;Pan Congyi;Liu Long;Fu Shiyi;Zhao Jianhui(College of Power and Energy Engineering,Harbin Engineering University,Harbin 150001,China)

机构地区：[1]哈尔滨工程大学动力与能源工程学院,黑龙江哈尔滨150001

出　　处：《内燃机学报》2024年第6期489-498,共10页Transactions of CSICE

基　　金：国家自然科学基金资助项目(T2341001);高技术船舶科研资助项目(CBG5N21-3-2).

摘　　要：面向高效率、低NO_(x)排放的氨燃料船机开发,利用Converge软件构建大缸径、高压直喷氨-柴双燃料发动机三维数值模型,基于氨部分预混的高压直喷预混-扩散混合控制燃烧模式,探究了引燃柴油单段和两段喷射策略及氨能量分数对缸内燃烧、单缸性能及NO_(x)排放的影响.结果表明:在低速机满负荷条件下,相同氨能量分数时,引燃柴油单段喷射可实现更高的指示热效率,但最大爆发压力和NO_(x)排放增加;两段喷射策略在氨能量分数为95%时,通过降低缸内高温且低氨质量分数区,在维持高指示热效率的同时,实现NO_(x)生成相比单段喷射策略分别降低29.6%和17.7%;此外,两种喷射策略下平均压力升高率和最大压力升高率对氨的喷射正时更加敏感.In order to achieve high thermal efficiency and low nitrogen oxides(NO_(x))emissions for ammonia-fueled marine engines,a 3-D numerical combustion model was developed based on Converge software for a large-bore low-speed direct-injection ammonia-diesel dual-fuel engine.The combustion was mainly based on a premixeddiffusion control,in which partially premixed ammonia was formed by high-pressure direct injection.The influences of both single-and two-stage pilot diesel injection strategies,as well as ammonia energy fraction,on in-cylinder combustion,performance and NO_(x) emissions were investigated.Results show that under the same ammonia energy fraction at full load,the single-stage injection of pilot diesel achieves higher indicated thermal efficiency(ITE),but the peak cylinder pressure and NO_(x) emissions increase.Under 95%ammonia energy fraction,the two-stage diesel pilot injection strategy achieves a reduction of 29.6%and 17.7%in NO_(x) emissions,and meanwhile maintains high ITE,compared to the single-stage injection strategy,due to reducing the high temperature and low ammonia mass fraction zone in the cylinder.In addition,it is found that,both the average and maximum of the rate of pressure rise are more sensitive to ammonia injection timing under both diesel pilot injection strategies.

关 键 词：双燃料发动机 高压直喷 喷射策略 氨能量分数 

分 类 号：TK470.1[动力工程及工程热物理—动力机械及工程]