在一台转速固定的火花点火发动机上进行了CO2稀释对CO掺氢混合燃料的燃烧及排放性能影响的试验研究。结果表明,氢气较快的燃烧速度弥补了由于其热值较低造成的对平均有效压力的影响,使得在每个当量比条件下平均有效压力基本保持不变。同时,掺氢对提升热效率及燃烧稳定性、改善CO以及NOx排放都有显著作用。适当的CO2稀释对平均有效压力和热效率的影响均不明显,而NOx排放水平则显著下降。但是过高的稀释率会导致部分燃烧,造成平均有效压力、热效率及CO排放的恶化。
The experiment of effect of CO2 dilution on combustion characteristics of H2-CO blended fuel by using a spark-ignition engine with fixed speed was carried out. The results showed that fast burning velocity of H2 offset its lower LHV, as a result, BMEP at each equivalent ratio kept almost constant. H2 substitution also benefited for thermal efficiency, engine stability, CO and NO, exhaust emissions. Suitable dilution hardly affected BMEP and thermal efficiency, but greatly reduced NO, emission. However, excess dilution induced to partial burn, which was bad for all these parameters of BMEP, thermal efficiency and CO emission.