高原环境 EGR 对生物质燃料柴油机性能的影响

摘要

In order to study the influences of performance and emissions of burning biomass fuel B25E5 and EGR system under plateau environment, the diesel engine stand tests were conducted. The experimental results show that while burning pure diesel, the power performance with the increase of EGR rate lowered under the working conditions of external characteristic, the falling range of 3%~15%;Under the working condition of load characteristic, EGR rate had no significant effect on the economy of diesel engine, the maximum combustion pressure in cylinder and the maximum combustion temperature decreased with the increase of EGR rate; Compared with the pure diesel fuel, when burned the B25E5 fuel, the dynamic performance felled slightly, the declining range was 2% ~ 12.5%; The specific fuel consumption rose, after opened the EGR, the economy became worse, the largest decline reached 29%; the change of maximum combustion pressure in cylinder and maximum combustion temperature were not obvious. Under different load conditions of the 2200 r/min, after burning biomass Fuel B25E5 and opened the EGR, the emissions of NOx felled, the average decline was 35%, the emission of smoke rose slightly, the average growth was 16%, the emissions of CO was not obvious.%为研究高原环境下 EGR 系统与燃用生物质燃料 B25E5对柴油机性能和排放的影响，进行了柴油机台架试验研究。试验结果表明：燃用纯柴油时，外特性工况下的动力性随着 EGR 率的增大而降低，降低的幅度为3%～15%；负荷特性下，EGR 率对柴油机的经济性无明显影响，缸内最高燃烧压力和最高燃烧温度随着 EGR率的增大均降低。与纯柴油相比，燃用生物质燃料 B25E5时，动力性有所下降，下降的幅度为2%～12%；燃油消耗率有所上升，开启 EGR 后，经济性最差，最大降幅达到29%；缸内最高燃烧压力和最高燃烧温度变化均不明显。在2200 r/min 的不同负荷工况下，燃用 B25E5并开启 EGR 后，NOx 排放量下降，平均下降幅度为35%，碳烟排放有小幅上升，平均增幅为16%，CO 的排放量无明显变化。