柴油机TR燃烧系统的设计与试验研究

Design and Experiment on Diesel TR Combustion System

通过比较HCCI燃烧和预混合近似等压燃烧理论,设计出了以“快速低压喷射、快速混合气形成和快速燃烧”为特征的柴油机TR(three rapidity)燃烧系统.该系统采用带中心喷孔的多孔喷油器,燃烧室四周壁面上设有导向圆弧,底部带有平顶凸台.另外,在一台 135单缸柴油机上对新系统进行了试验研究.结果表明,在与原机相同的供油提前角下,新系统满负荷工况下的油耗率降低 1600左右,波许烟度值降低 8000,NOx浓度有所增加.进一步推迟供油后,波许烟度值有所上升,NOx迅速降低.供油提前角为 13°CABTDC时,烟度值和NOx浓度都比较低.

Through the comparison between HCCI (homogeneous charge compression ignition) combustion and premixed approximate isotonic combustion theory, the author designed the diesel TR (three-rapid) combustion system, which is characterized by rapid low-pressure fuel injection, rapid formation of combustible mixture and rapid combustion rate. The new system adopts a multi-hole nozzle with a central hole. An oriented arc is set on the wall of the chamber, and there is a plane convex at the central bottom of the chamber. A performance test of the new combustion system was made on a 135 diesel. The results show that, with the same fuel supply advance angle, the fuel consume rate of the new system reduces by about 16% of that of the original diesel averagely and the exhaust smoke decreases by 80% when the diesel is operating under full load condition. However, the concentration of nitrogen oxides increases. When the fuel supply advance angle is delayed further, the exhaust smoke increases slightly while the concentration of nitrogen oxides decreases sharply. When the fuel supply advance angle is set as 13°CA BTDC, smoke and the concentration of NOx are both low.