Abstract Biodiesel is widely accepted as substitute fuel for diesel engine by scientist, engineers and researchers for its superior fuel quality compared to diesel in terms of emission. The environmental and social benefits got from biodiesel attract almost all section of people. The use of biodiesel in diesel engine reduces the green house gases like CO, HC and PM emission considerably, but the smoke and NOx emissions are high compare to diesel. In order to reduce the smoke and NOx emissions caused by biodiesel in diesel engine, an experimental study was conducted by using water emulsified pongamia biodiesel in a four stroke direct injection diesel engine. The result revealed 9% increase in BSFC and 5% decrease in BTE with a reduction of around 32% in NOx emission. The smoke has been reduced to 7.4%, the emission of CO and HC has been reduced to a marginal value of 2.3% and 1% respectively compared with that of B20 blend.

中文翻译：

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水乳化混合水黄生物柴油作为改性燃料，用于对直喷柴油发动机的性能、燃烧和排放特性进行实验分析

摘要 生物柴油因其在排放方面优于柴油的燃料质量而被科学家、工程师和研究人员广泛接受为柴油发动机的替代燃料。生物柴油所带来的环境和社会效益吸引了几乎所有阶层的人。在柴油发动机中使用生物柴油可显着降低 CO、HC 和 PM 等温室气体的排放，但与柴油相比，烟尘和氮氧化物排放量较高。为降低柴油机中生物柴油产生的烟气和NOx排放，在四冲程直喷柴油机上使用水乳化水黄生物柴油进行了试验研究。结果显示 BSFC 增加 9%，BTE 减少 5%，NOx 排放量减少约 32%。烟雾减少到7.4%，