点火时刻对缸内直喷低热值气体燃料掺氢燃烧发动机性能影响的试验

Experiment of combustion characteristics of a direct in jection engine fueled with low heating value gas-hydrogen blends under different ignition timings

在一台改装的单缸气体发动机上进行了缸内直喷低热值气体燃料掺氢燃烧的试验，开展了不同掺氢比例下，点火提前角对发动机动力和排放及经济性的影响研究．低热值燃料由天然气含量为45％～65％，N2含量为35％，掺氢含量为0-20％的气体组成．研究结果表明：随着掺氢比例的增加，发动机动力性呈现先增高后降低趋势，在掺氢10％条件下动力性最好；排放污染物中HC排放增大，NOx排放呈先增大后减小的趋势，在掺氢10％条件下排放最多，但CO排放基本不变．

The experiment of combustion characteristics of a direct-iniection spark-ignited engine fueled with low heating gas- hydrogen blends under various ignition timings was investigated. The compo- nents of low heating gas contain natural gas, nitrogen and hydrogen. The natural gas content is from 45 % to 65 %, N2 content is 35 %, and the hydrogen blending ratio is from 0 % to 20 %. The results show that the engine power increases and decreases with the increase of hydrogen fraction in low heat- ing gas. When the hydrogen is 10 %, it gives the maximum power. After exhaust HC concentration has increased, the exhaust NOx concentration will first increase and then decrease with the increase of hydrogen fraction in low heating gas and the exhaust CO will give little variation under various ignition timings and the fraction of hydrogen.