进气系统耦合燃烧室形状对船用柴油机燃烧和排放的影响  

Effect of Intake System Coupled with Combustion Chamber on Combustion and Emission Characteristics for a Marine Diesel Engine

作　　者：赵昌普[1] 王耀辉[1] 孙雅坤 张志刚 朱亚永 郑尊清[1] Zhao Changpu;Wang Yaohui;Sun Yakun;Zhang Zhigang;Zhu Yayong;Zheng Zunqing(State Key Laboratory of Engines,Tianjin University,Tianjin 300072,China)

机构地区：[1]天津大学内燃机燃烧学国家重点实验室,天津300072

出　　处：《燃烧科学与技术》2018年第1期1-8,共8页Journal of Combustion Science and Technology

基　　金：国家高技术研究发展计划(863计划)资助项目(2012AA111705)

摘　　要：以AVL程序为计算平台,采用Boost和Fire软件分别建立柴油机一维和三维仿真模型进行模拟计算,利用Miller循环和EGR技术来降低缸内燃烧温度,并通过燃烧室和涡流比的合理匹配来改善缸内的油气混合,从而减少排放物生成,满足越来越严格的排放法规.结果表明,随进气门关闭正时的提前,缸内温度逐渐降低,NO_x排放减小,但进气门关闭过早会增加NO_x排放;燃烧室结构的优化并匹配合理的初始涡流比能够改善缸内流动,进一步减少排放,增加指示功率;EGR策略可以弱化缸内高温分布,减少NO_x排放,但碳烟排放有所增加.采用改进的燃烧室和涡流比并匹配Miller循环和EGR技术可使NO_x排放降低96.5%,,同时使功率输出略有增加.In order to meet more and more stringent emission regulation,numerical study was conducted to investigate the temperature reduction effect of Miller cycle coupled with intake turbocharging system and EGR(exhaust gas recirculation)as well as the better fuel-air mixing effect of combustion chamber modification and initial swirl ratio based on AVL Boost and Fire.The results show that with the advance of Miller timing,the temperature in cylinder decreases,and the NOx emissions decrease as well,while the premature intake valve close timing increases NOx emission.The modification of combustion chamber and reasonable initial swirl ratio can improve the fuel-air mixing inside the cylinder,reduce emissions and increase the indicated power.EGR strategy can evidently reduce high temperature distribution and NOx emission,while soot emission increases.The optimization of Miller cycle,combustion chamber,initial swirl ratio and EGR can reduce NOx emission by 96.5%and slightly increase output power.

关 键 词：柴油机 Miller正时 燃烧室形状 涡流比 EGR NOx 数值模拟 

分 类 号：TK421.2[动力工程及工程热物理—动力机械及工程]