论文部分内容阅读
利用快速压缩装置进行了喷射方式对直喷汽油分层燃烧的影响研究。研究结果表明 :在当量比小于 0 .5时 ,快速燃烧期保持相同的数值而与喷射方式无关 ;在当量比大于 0 .5时 ,单点喷射方式比双点喷射方式具有较长的快速燃烧期。双点喷射方式的后燃期随当量比的增加而缩短 ,而单点喷射方式的后燃期随当量比的增加而增长。双点喷射方式的燃烧持续期基本上保持一稳定值而不随当量比的改变而变化 ,单点喷射方式下较长燃烧持续期出现在大当量比区域。双点喷射方式由于燃烧持续期短和放热速率快而呈现高的压力升高值。CO在当量比小于 0 .8时具有很低的数值 ,而在当量比大于 0 .8时因强充量分层则随当量比的增加而急速上升。三种喷射方式下碳氢随当量比的增加而增加。双点喷射和单点喷射的 NOx 的最大值分别出现在 0 .6～0 .7和 0 .3～ 0 .5区域处。在当量比小于 0 .8时 ,CO2 不受喷射方式的影响。燃烧效率在当量比 0 .15～ 0 .90范围内均达到 0 .9以上而基本上不随喷射方式而改变
Effect of Jetting Mode on Stratified Combustion of Direct Injection Gas Using Rapid Compression Device. The results show that when the equivalence ratio is less than 0.5, the fast burning period keeps the same value regardless of the spraying method. When the equivalent ratio is more than 0.5, the single-point spraying method has a longer rapid combustion than the two-point spraying method period. The post-combustion period of the two-point injection method is shortened as the equivalence ratio increases, while the post-combustion period of the single-point injection method increases with the equivalence ratio. The combustion duration of the two-point injection method basically maintains a stable value without changing with the equivalence ratio change. In the single-point injection mode, the longer combustion duration appears in the area of large equivalence ratio. The two-point injection method presents a high pressure increase due to the short duration of combustion and rapid heat release rate. CO has a very low value when the equivalence ratio is less than 0.8, while when the equivalence ratio is more than 0.8, the stratification due to strong charge increases rapidly with the equivalence ratio. Hydrocarbons increased with the increase of equivalence ratio under the three injection modes. The maximum values of NOx for two-point injection and single-point injection appear in the region of 0.6 ~ 0.7 and 0.3 ~ 0.5, respectively. When the equivalence ratio is less than 0.8, CO2 is not affected by the spraying method. Combustion efficiency in the equivalent ratio of 0.15 ~ 0.90 range of more than 0.9 but basically does not change with the injection method