柴油机燃用掺水燃料的燃烧特性及其节油机理分析

An Analysis of the Combustion Characters and the Mechanism for Fuel Consumption Saving of Diesel Engine Using Water-Blended Fuel

通过计算对掺水的综合效果进行了分析 ,结果表明 :1)与纯柴油相比 ,掺水燃料喷射液体总量增多 ,存在时间变长 ,液雾卷吸能力增强 ,能更加充分地与空气混合使燃烧完全 ,在上止点附近热量释放集中使柴油机做功能力增强 ,是提高燃烧效率的主要原因之一 ;2 )燃料中水蒸发做功可以部分弥补由于水分蒸发使温度和压力下降所造成的不利影响而提高功率 ,这是节油的第 2个重要原因 ;3)掺水后尽管排气带走的水蒸汽潜热会增加 ,但是同时排气最高温度与平均温度都有所下降 ,排气损失反而减小 ,这是节油的第

In the present paper,a detailed analysis for the effect of water in emulsion fuel has been conducted and the results show that (1) compared with fuel without water,the stronger convolution ability of emulsion,leading to more complete combustion and a more rapid heat release process,which may contribute to the enhancement of engine efficiency,is one of the main reason for reducing oil consumption;(2)the engine power output will be improved by an increased chamber pressure because of more water steam from emulsion,which will partly overcome the disadvantages of heat absorption by water vaporization and contribute to the lower fuel consumption;(3)although more latent heat of water vapor might be lost in exhaust with the increase of the amount of water additon,the temperature in the chamber will be depressed too and total enthalpy loss is less in stead,which is another main reason for reducing fuel consumption.