直喷式发动机燃用天然气掺氢混合燃料放热规律与燃烧特征参数分析  

Heat Release and Combustion Characteristic Parameters of a Direct Injection Engine Fueled with Natural Gas/Hydrogen Blends

作　　者：王金华[1] 方宇[1] 黄佐华[1] 刘兵[1] 曾科[1] 苗海燕[1] 蒋德明[1] 

机构地区：[1]西安交通大学动力工程多相流国家重点实验室,西安710049

出　　处：《燃烧科学与技术》2008年第2期107-112,共6页Journal of Combustion Science and Technology

基　　金：国家自然科学基金(50636040);国家重点基础研究发展计划(973)资助项目(2003CB214501);优秀国家重点实验室研究资助项目(50323001);国家自然科学基金创新群体资助项目(50521604)

摘　　要：研究了直喷发动机燃用天然气掺氢混合燃料的放热规律与燃烧特征参数,研究结果表明:随着混合燃料中氢气体积分数的增加,中、低负荷发动机有效热效率增加,大负荷下有效热效率高且基本上不随氢气体积分数变化;随着氢气体积分数的增加,混合燃料放热率曲线相位提前,快速燃烧期缩短,放热率增加,此现象在低转速工况下更为明显,表明气流速度较低时掺氢对提高混合燃料燃烧速率作用明显;缸内最高燃气平均温度、最大压力升高率和最大放热速率随氢气体积分数增加而增加.A study on heat release and combustion characteristic parameters of a direct injection spark ignited engine fueled with natural gas/hydrogen blends was carried out. The results showed that the brake effective thermal efficiency increased with the increase of hydrogen fraction at low and medium loads. High thermal efiqciency was achieved at high loads and didn＇t vary with the variation of hydrogen fraction. With the increase of hydrogen fraction the phase of the heat release curve advanced, rapid combustion duration decreased and heat release rate increased. This phenomenon was more obvious at the low speed operating mode, revealing relatively high enhancement of burning velocity of mixtures by hydrogen addition in the case of weak air motion in cylinder. The maximum mean gas temperature, pressure rise rate and heat release rate increased with the increase of hydrogen fraction.

关 键 词：缸内直喷 发动机 天然气 氢气 放热规律 燃烧特征参数 

分 类 号：TK431.2[动力工程及工程热物理—动力机械及工程]