柴油机燃用乙醇-柴油-汽油混合燃料的试验研究(英文)

Experimental Study on Diesel Engine Fueled with Ethanol-Diesel-Gasoline Blends

以汽油为助溶剂配制出均匀稳定的乙醇-柴油-汽油混合燃料,在单缸四气门135柴油机上对燃用不同配比混合燃料及使用不同油嘴型式进行了性能试验。结果表明:燃用适当配比的乙醇-柴油-汽油混合燃料,柴油机动力性、经济性基本不变,碳烟和NOx排放下降明显;着火滞燃期延长,缸内平均温度下降,燃烧速率加快,燃烧持续期缩短;当使用HL伞喷油嘴燃用E20G15燃料时,着火滞燃期进一步延长,油气混合速率和混合气均匀度明显提高,在整个工况范围内,气缸压力和缸内平均温度均较低,碳烟和NOx排放同时降低,其燃烧过程具有明显的热预混合燃烧特征。

The homogeneous and stable ethanol-diesel-gasoline blend fuel is formed by using gasoline as the solubilizer. The perform- ance experiments are carried out on 135 single-cylinder 4-valve diesel engine withdifferent mixture rate of this new blend-fuel and dif- ferent nozzle modes. The results show the following conclusions： fueled with appropriate rate ethanol-diesel-gasoline blend fuel, the engine power output and fuel economy of engine keep the same level to those of diesel fuel operation while the soot and NOx emission decreased remarkably; at the same time, ignition delay period prolongs, in -cylinder mean temperature decreases, combustion velocity becomes higher, combustion duration becomes shorter. When HL conical spray nozzle and the E20G15 blend fuel are used, the fuel/ air mixing velocity and the homogeneous of mixture are improved, in the whole operation range, in-cylinder pressure and mean temperature are both lower, moreover, soot and NOx emission are decreased; the combustion process has obvious characteristics of hot premixed combustion mode.