喷水时刻对内燃郎肯循环燃烧及排放特性影响

Effect of Water Injection Phasing on Combustion Process in ICRC Engine

摘要:

利用自主开发的内燃郎肯循环（ICRC）发动机试验台架对基于此循环的发动机工作过程进行试验研究.以氧气和二氧化碳混合气模拟废气再循环(EGR)控制燃烧速度，研究喷水时刻对燃烧及排放特性的影响.结果表明：高温水在控制反应速率的同时汽化膨胀做功，拓宽示功图的有效面积；最高可将循环热效率提高6.3%；喷水时刻对热效率影响不大，但较早的喷水时刻最多可导致碳氢排放增加40%.

Abstract:

Working process of an internal combustion Rankine cycle (ICRC) is studied based on bench tests of a prototype engine. A minture of O2 and CO2 is ased used to simulate eshaust gas recirculation(EGR) to control the combastion rate, and effect of injection phase on the combustion and emission characteristics is studied. Results show that water with injection temperature of 160℃ can not only control the reaction rate, but also can expand the area of the P V diagram through vaporization. As a result, the thermo efficiency increases by 6.3%. Injection phase does not affect the thermo efficiency obviously, however, earlier injection timing can increase HC emissions by 40%.