热强化对乙醇柴油发动机性能及排放的影响

Combustion Performance and Exhaust Emission of DI Diesel Engine with Heated Ethanol-Diesel Fuel Blends

通过模拟发动机冷却水废热回收利用的水浴加热法,对流经喷油泵后高压油管的乙醇柴油混合燃料进行预热升温,以探讨不同乙醇柴油配比及其热强化对发动机性能、常规与非常规污染物排放特性的影响.试验结果表明,与常温燃油相比,乙醇柴油热强化有利于降低发动机在低转速和部分负荷工况下的当量燃油消耗率及其HC排放,而其碳烟和NOx排放无明显变化;乙醇柴油热强化还可降低乙醛、丙酮和乙醇等非常规污染物排放,但会使中低转速工况下的甲醛的排放稍有增加.

The performance and exhaust emission of a DI diesel engine running on ethanol-diesel blends at normal and elevated fuel temperatures were evaluated experimentally. The temperature of the blended fuel was increased by heating the post-pump high pressure fuel pipe. The effects of blended fuel temperature and different blends of ethanoldiesel on engine performance,regulated and unregulated emissions were studied. The results show that increasing the blended fuel temperature was beneficial for the reduction of equivalent fuel consumption and HC emission under partload and low speed engine operation while brought about no significant changes to smoke and NOx emissions as compared with operation at normal fuel temperature. It is also found that increasing the blended fuel temperature resulted in the decrease of acetaldehyde,acetone and ethanol emissions,but the increase of formaldehyde emission at low engine speed.