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

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.