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一种应用在135柴油机上的新型燃烧系统TR(Three-Rapidity),是由收口深坑ω形燃烧室改进而成,在壁面设置导向圆弧,并与带中孔的多孔喷嘴相匹配.应用STAR-CD软件对TR燃烧系统在50%负荷下的工作过程进行三维数值模拟,并与原机燃烧系统相比较.结果表明,TR燃烧系统的着火点控制在上止点附近,增加了预混合燃烧的比重.采用导向圆弧、缩口燃烧室和中孔喷射,气流运动更加剧烈,燃油空间分布合理,空气利用充分,减少壁面散热损失,并具有良好的冷启动性能.在135单缸柴油机上进行试验研究,和原机相比TR燃烧系统具有良好的烟度排放特性,NOx排放在中小负荷低于原机排放,在高负荷则有所增加,可通过推迟喷油来解决.TR燃烧系统在降低柴油机排放方面具有较大的潜力,对原机结构改动较少,具有广阔的应用前景.
A new type of combustion system, TR (Three-Rapidity), applied to a 135 diesel engine, is a retrofitted deep-bore o-shaped combustion chamber with guide arcs on the wall and matching with a multi-hole nozzle with a mesopore. STAR-CD software is used to simulate the working process of TR combustion system under 50% load and compare with the original combustion system.The results show that the ignition point of TR combustion system is controlled near TDC, and the premixed combustion is increased Of the proportion of the use of the guide arc, the neck of the combustion chamber and the injection hole, the air flow more intense, rational distribution of fuel space, adequate use of air to reduce wall heat loss, and has good cold start performance in the 135 single cylinder diesel engine Compared with the original engine, the TR combustion system has good smoke emission characteristics, NOx emission is lower than that of the original machine at medium and small load and increased at high load, which can be solved by delaying fuel injection.TR combustion system It has great potential in reducing emission of diesel engines and has few changes to the original aircraft structure and has broad application prospect.