点火能量对LPG小型点燃式发动机排放的影响

结合四冲程、水冷125 mL单缸电控喷射摩托车发动机,对LPG在小型点燃式发动机上应用时,点火能量的改变对发动机排放的影响进行了试验研究。设计了一个可变点火能量的单片机控制蓄电池直流供电式CD I点火器,通过改变点火能量,研究分析了各种混合气浓度下排放的变化。结果表明:浓混合气条件下,点火能量对排放并没有明显影响,但在稀混合气条件下,点火能量的改变对LPG发动机的排放影响很大,增大点火能量可以有效增大失火界限,拓宽LPG发动机稀薄燃烧区的范围。

Effects of Ignition Energy on Emission Behavior

The effect of the spark energy on the emissions was investigated on a small LPG SI engine (125 mL, 4-stroke, water-cooled, single-cylinder, with electronically controlled fuel injection). A microcomputer-controlled DC-CDI igniter was designed, and the exhaust emissions from the engine under different mixture concentrations were studied by changing the adjustable ignition energy. The results show that the ignition energy has little effect on the emissions while the mixture is rich, but much effect while the mixture is lean. Increasing ignition energy can expand the limit of misfire and widen the lean-burn range of LPG engine.