不同喷射策略下CRDI柴油机燃用柴油-桐油-乙醇混合燃料的燃烧与排放特性

在1台共轨直喷(CRDI)柴油机上开展了不同喷射策略下桐油、乙醇与柴油混合燃料的燃烧和排放特性研究。试验结果表明:与0号柴油相比,混合燃料的着火延迟期稍长,缸内压力峰值和放热率较高,但燃烧持续期稍短;随着桐油和乙醇体积分数的增加,有效热效率(BTE)也随之增大。在低负荷时,混合燃料的CO和HC排放较高,且随着桐油和乙醇所占体积分数的增大而增加;混合燃料的NO_x排放在低负荷时较低,在高负荷时略高;在高负荷时,混合燃料的炭烟排放大大减少。总体而言,混合燃料中乙醇对发动机性能的影响比桐油大。

Combustion and Emission Characteristics of CRDI Diesel Engine Fueled with Diesel-Tung Oil-Ethanol Blends under Different Injection Strategies

The combustion and emission characteristics of tung oil,ethanol and diesel mixed fuel under different injection strategies were studied on a common rail direct injection(CRDI)diesel engine.The experimental results show that the ignition delay period of blends are slightly longer than that of 0#diesel,the peak pressure and heat release rate are higher,but the combustion duration is slightly shorter.With the increase of the volume fraction for tung oil and ethanol,the brake thermal efficiency(BTE)increased.The emissions of CO and HC are higher at low load and increase with the increase of both mixing volume fraction.The NO_xemission is lower at low load and slightly higher at high load,and the soot emission greatly reduces at high load.In general,ethanol has a greater influence on engine performance than tung oil.