【摘要】 基于一台2.0 L涡轮增压直喷氢内燃机，试验了稀薄燃烧下直喷氢内燃机的近零排放(NO_x排放小于20×10^-6)工作特性，在中高转速（2 000～3 500 r/min）下，近零排放时平均有效压力均达到1 MPa以上，相比于自然吸气状态，动力性提升了2.6倍．进一步针对不同喷氢相位和喷氢压力进行了全工况研究，结果表明：当喷氢结束角为80°CA BTDC时，在近零排放边界下，可以同时达到最大的平均有效压力和最高有效热效率．优化后的近零排放氢内燃机最高转矩达到204 N·m（2 500 r/min），最大功率提升至72 kW（3 500 r/min），最高有效热效率达到41.5%（2 000 r/min）；可在全转速工况下实现乘用车常用工况范围的近零排放．提出的优化方法可以指导高效近零排放氢内燃机控制策略的开发．更多还原

【Abstract】 Thermal efficiency and near-zero NO_x emission(NO_x<20×10^-6)were experimentally optimized on a 2.0 L turbocharged direct injection hydrogen engine with lean combustion. The experiments were carried out at large load and speed operating range with different injection phases and pressures. At speed range of 2 000-3 500 r/min,near-zero NO_x emission could be achieved at an average effective pressure exceeding 1 MPa and the power output is 2.6 times higher than that under the naturally aspirated condition. It is found that the highest brake mean effective pressure and brake thermal efficiency can be achieved when the end of hydrogen injection timing is 80° CA BTDC. After optimization,the hydrogen engine reaches the maximum torque of 204 N·m at 2 500 r/min,the maximum power of 72 k W at 3 500 r/min and the highest effective thermal efficiency of 41.5% at 2 000 r/min. Near-zero NO_x emission range covers the common operating conditions of passenger cars. The experimental results are used to develop control strategies for the high-efficiency near-zero emission hydrogen engine.更多还原