不同喷射方式对柴油/甲醇组合燃烧尾气中甲醛排放的影响

在一台经过改装的压燃式柴油机上进行了柴油/甲醇组合燃烧试验,对比了甲醇的不同喷射方式(顺序喷射与连续喷射)对组合燃烧尾气中甲醛排放的影响.试验结果表明,顺序喷射方式下尾气中的甲醛浓度要低于连续喷射尾气中的结果,在低负荷工况时,顺序喷射最大降低量达32%,在中高负荷工况下,两种喷射方式的甲醛排放相差不大.对比甲醇对柴油相同替代率时,两种喷射方式均表现在低负荷时的甲醛排放最多,而且甲醛排放差值也较大.此外,试验结果还表明,顺序喷射的燃料经济性要优于连续喷射.

Influence of methanol injection styles on formaldehyde emissions from a DMCC engine

A diesel/methanol compound combustion engine (DMCC) was operated on a test bench to compare the influence of methanol injection modes. Continuous Fuel Injection (CFI) and Sequential Fuel Injection (SFI) were compared and the formaldehyde emission characteristics were investigated. The formaldehyde emissions from SFI mode were less than from CFI, especially at low load, where the formaldehyde emission was about 32% less in SFI mode. The difference of formaldehyde emission in the two modes was not obvious at intermediate load and high load. When the engine was run at the same proportion of methanol to diesel in the fuel, formaldehyde emission concentration reached a maximum at low loads in both methanol injection modes. At intermediate and high loads, the formaldehyde emissions were comparable. In addition, the SFI mode had better fuel economy than the CFI mode.