环境温度对掺水乳化柴油喷雾燃烧特性的影响  

Effects of Ambient Temperature on Spray and Combustion Characteristics of Water Emulsified Diesel

作　　者：王兆文[1] 石书国 黄胜[1] 唐劼 杜涛 成晓北[1] Wang Zhaowen;Shi Shuguo;Huang Sheng;Tang Jie;Du Tao;Cheng Xiaobei(Department of Energy and Power Engineering,Huazhong University of Science and Technology,Wuhan 430074, China;Shanghai Stirling Engine Research Centre,Shanghai 201203,China)

机构地区：[1]华中科技大学能源与动力工程学院,湖北武汉430074 [2]上海热气机工程技术研究中心,上海201203

出　　处：《内燃机学报》2019年第3期203-212,共10页Transactions of Csice

基　　金：国家自然科学基金资助项目(51576083)

摘　　要：柴油机中燃用掺水乳化柴油有提高燃烧热效率的潜力,并同时降低碳烟和NOx排放.利用定容燃烧弹台架,对比试验了纯柴油和掺水乳化柴油的燃烧特性,并重点研究了环境温度对掺水乳化柴油喷雾和燃烧特性的影响.结果表明:相比于纯柴油,掺水乳化柴油能明显降低燃烧过程中碳烟的生成量;掺水乳化柴油中水的蒸发和微爆作用随环境温度的升高逐渐增强,能有效促进喷雾雾化和油、气混合过程;随着环境温度的升高,掺水乳化柴油的滞燃期及火焰升举长度均减小,燃烧火焰亮度增大.高环境温度工况下,碳烟前期生成速率和后期氧化速率均增大,使得不同环境温度工况下掺水乳化柴油最终碳烟的排放量相差较小.The use of water emulsified diesel fuel in diesel engines can potentially improve the thermal efficiency and reduce NOx and soot emissions simultaneously. An experiment was conducted in a constant volume combustion chamber in order to investigate the combustion process between neat diesel and water emulsified diesel. In particular,the effect of ambient temperature on the spray and combustion characteristics was discussed. The results indicate that soot emission is significantly reduced with the use of water emulsified diesel. As the ambient temperature increases,the effects of fuel evaporation and micro-explosion of water on spray breakup and fuel-air mixing processes are enhanced. As a result,the measured ignition delay and flame lift off length are reduced,and the integrated natural flame luminosity is increased. Under high ambient temperature conditions,the generation rate and oxidation ratio of soot are increased,resulting in an almost equal soot emission for various ambient temperatures in water emulsified diesel.

关 键 词：掺水乳化柴油 定容燃烧弹 环境温度 喷雾燃烧 

分 类 号：TK421[动力工程及工程热物理—动力机械及工程]