摘要
通过在柴油机上燃用生物柴油(Biodiesel)、微乳化油生物柴油(MB)、乙醇柴油(E20)与纯柴油4种燃料,研究在低含氧量情况下不同含氧结构对柴油机燃烧和排放性能的影响。结果表明,相较于纯柴油,标定点工况下,生物柴油着火时刻约提前2°CA,放热率峰值和最大爆发压力略有降低,而MB和E20放热始点相对滞后,但放热过程更集中。大负荷时,发动机燃用3种含氧燃料总体表现为NOx排放增加,而HC、CO和烟度等均有不同程度的下降;但中低负荷时,E20的HC和CO排放明显较高。对于酯基或醇基不同结构来源的含氧燃料,携带氧的碳链长短及其附属燃料特性造成其燃烧和排放性能的显著差异,需根据各自属性优化在柴油中的添加比例,协调含氧燃料在发动机上的应用。
The effects of different oxygen structures of low-oxygen fuels on diesel engine combustion and emission characteristics were investigated, by using biodiesel, micro-emulsified biodiesel （MB） , ethanol-diesel （E20） and pure diesel in a diesel engine, respectively. The results show that the ignition timing of biodiesel is about 2° CA in advance, and both the peak heat release rate and the maximum cylinder pressure are slightly lower, while the start timings of heat release of MB and E20 are relatively delayed, but the heat release process is more concentrated, which compared with pure diesel under the rated operating condition. At higher loads, the emission performance of three oxygenated fuels behaves that NOx emissions increase, while HC, CO and smoke decline at different levels. At lower and medium loads, HC and CO emissions of E20 are significantly higher. As tbr ester group or alcohol group of different structure sources of oxygen fuels, the length of carrying oxygen carbon chain and the affiliated fuel characteristics cause the significant difference of combustion and emission characteristics. So it is necessary to coordinate the application of three oxygen fuels on the diesel engine by optimizing additive proportion in diesel fuel according to their respective attributes.
出处
《汽车工程学报》
2013年第1期34-39,共6页
Chinese Journal of Automotive Engineering
基金
国家自然科学基金资助项目(51076069)
江苏高校优势学科建设工程资助项目(苏政办发〔2011〕6号)
关键词
柴油机
含氧燃料
燃烧过程
排放
diesel engine
oxygenated fuel
combustion process
emission
