Xinling Li, Zhen Huang
Key Laboratory of Power Machinery and Engineering of Education Ministry, Shanghai Jiao Tong University, Shanghai 200240, China.
Sci Total Environ. 2009 Mar 15;407(7):2234-44. doi: 10.1016/j.scitotenv.2008.11.043. Epub 2008 Dec 23.
A study of engine performance characteristics and both of regulated (CO, HC, NO(x), and smoke) and unregulated (ultrafine particle number, mass concentrations and size distribution) emissions for a turbocharged diesel engine fueled with conventional diesel, gas-to-liquid (GTL) and dimethyl ether (DME) fuels respectively at different engine loads and speeds have been carried out. The results indicated that fuel components significantly affected the engine performance and regulated/unregulated emissions. GTL exhibited almost the same power and torque output as diesel, while improved fuel economy. GTL significantly reduced regulated emissions with average reductions of 21.2% in CO, 15.7% in HC, 15.6% in NO(x) and 22.1% in smoke in comparison to diesel, as well as average reductions in unregulated emissions of total ultrafine particle number (N(tot)) and mass (M(tot)) emissions by 85.3% and 43.9%. DME can significantly increase torque and power, compared with the original diesel engine, as well as significantly reduced regulated emissions of 40.1% in HC, 48.2% in NO(x) and smoke free throughout all the engine conditions. However, N(tot) for DME is close to that for diesel. The reason is that the accumulation mode particle number emissions for DME are very low due to the characteristics of oxygen content and no C-C bond, which promotes the processes of nucleation and condensation of the semi-volatile compounds in the exhaust gas, as a result, a lot of nucleation mode particles produce.
分别对一台涡轮增压柴油发动机在不同发动机负荷和转速下使用常规柴油、气制油（GTL）和二甲醚（DME）燃料时的发动机性能特性以及常规排放物（一氧化碳、碳氢化合物、氮氧化物和烟尘）和非常规排放物（超细颗粒数量、质量浓度和粒径分布）进行了研究。结果表明，燃料成分对发动机性能以及常规/非常规排放有显著影响。GTL的功率和扭矩输出与柴油几乎相同，同时燃油经济性有所提高。与柴油相比，GTL显著降低了常规排放，一氧化碳平均降低21.2%，碳氢化合物平均降低15.7%，氮氧化物平均降低15.6%，烟尘平均降低22.1%，非常规排放中的总超细颗粒数量（N(tot)）和质量（M(tot)）排放也分别平均降低了85.3%和43.9%。与原柴油发动机相比，DME能显著提高扭矩和功率，并且在所有发动机工况下都能显著降低常规排放，碳氢化合物降低40.1%，氮氧化物降低48.2%且无烟尘排放。然而，DME的N(tot)与柴油接近。原因是由于DME的含氧量特性和无碳 - 碳键，其积聚模式颗粒数量排放非常低，这促进了废气中半挥发性化合物的成核和冷凝过程，结果产生了大量的成核模式颗粒。
