中文摘要：

在一台改装的单缸气体发动机上进行缸内直喷不同 CH4/N2配比的混合燃料发动机掺氢燃烧负荷特性的试验，研究不同负荷下混合燃料中掺氢比和掺氮比对发动机动力性、排放性以及经济性的影响。研究结果表明，当混合气体燃料中氮气体积分数不同时，不同负荷区域，掺入氢气对缸内最大爆发压力影响不同。结果显示，掺氮25%燃料CO排放较掺氮15%的明显增大，且当不掺氢时，增长近30%，并且掺氢对减小HC排放有利，但氢气对不同氮气比燃料CO排放与NOx排放影响不同，对于掺氮15%燃料，掺氢10%后，CO排放升高，NOx排放降低，而对于掺氮25%燃料掺氢后CO排放降低，NOx排放升高。另外，随着负荷增大，有效燃气消耗率呈逐渐减小的趋势，而且掺氢有利于热效率的提高。

英文摘要：

The purpose of this research is to investigate a direct-injection single-cylinder engine fueled with different proportions of CH4 and N2-hydrogen blends under various engine load, the different influences of the proportion of hydrogen and nitrogen under various engine loads to the engine’s power, emission and efficiency are studied. The result shows that, in different load areas, when the percentages of N2 vary in the mixed gas fuel, adding H2 would have a different effect on the fraction on the maximum break pressure in the cylinder. The results also reveal that the emission of CO in the fuel within 25% N2 increases obviously than that within 15% N2. When there is no H2 in the fuel, the emission of CO increases nearly 30%. In addition, blending H2 is helpful to decrease the emission of HC. However, H2’s influence to the emission of CO in fuel with different percentages of N2 is different from its influence to the emission of NOx. When the fuel within 15%N2 is blended with 10%H2, the emission of CO increases but the emission of NOx decreases. Whereas, when the fuel within 25% N2 is blended with H2, the emission of CO decreases and the emission of NOx increases. Furthermore, with the engine load increasing, the effective gas consumption rate decreases. And blending hydrogen contributes to the increase of thermal efficiency.