为了分析天然气掺氢燃料对发动机动力性、经济性和排放性的影响,在一台电控单缸天然气发动机上开展了体积掺氢比分别为15%、20%和25%的天然气掺氢燃料的试验和过量空气系数对发动机性能的影响试验.结果表明,在特定发动机工况下,随着掺氢比的增加,缸内最高压力随之增加;NOx排放量增大,而HC、CO排放量降低;有效燃气消耗率降低.试验结果也表明稀燃可以改善发动机的排放性能.
The aim of this study is to evaluate the power, efficiency and emissions of an electronic-controlled single-cylinder engine fuelled with blends of pure natural gas and natural gas-hydrogen, whose hydrogen fraction varied from 15 % to 25% in volume with a 5% interval, respectively. The effects of excessive air-fuel ratio were discussed. The results show that the maximum cylinder gas pressure increases with the increase of hydrogen fraction under certain engine conditions. The increase of hydrogen fraction in the blends contributed to the increase of NOx and the decrease of HC and CO. The brake specific fuel consumption decreased with the increase of hydrogen fraction. Using HCNG at relatively leaner fuel-air mixtures can drop the engine emissions.