柴油机预燃室射流扰动燃烧系统的设计与试验  

Design and Experiment of a Prechamber Jet Disturbed Combustion System for Diesel Engine

作　　者：聂靖宇 刘一泽 王家勇 邬斌扬[1] 苏万华[1] Nie Jingyu;Liu Yize;Wang Jiayong;Wu Binyang;Su Wanhua(State Key Laboratory of Engines,Tianjin University,Tianjin 300350,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300350

出　　处：《内燃机学报》2023年第4期289-297,共9页Transactions of Csice

基　　金：国家重点研发计划资助项目(2022YFE0100100);国家自然科学基金资助项目(51921004).

摘　　要：为了实现重型柴油机大负荷工况下的高效清洁燃烧,设计了一种应用于重载柴油机的预燃室射流扰动燃烧系统,旨在利用预燃室产生的射流动量促进柴油机大负荷工况下的油、气混合过程,提高扩散燃烧的速度,增大燃烧等容度,从而提高发动机的指示热效率.建立预燃室仿真模型,研究预燃室射流的作用位置、持续时间、动量大小及作用相位对油、气混合与燃烧过程的影响,以缩短发动机燃烧持续期、提高指示热效率为目标,对预燃室的结构进行优化.基于仿真结果,搭建了预燃室射流扰动燃烧系统的试验平台并进行试验.结果表明:在没有明显提高排放的前提下,采用预燃室射流扰动燃烧系统可以有效缩短大负荷工况下的燃烧持续期,提高指示热效率.在转速为1200r/min、平均指示有效压力(IMEP)为2.54 MPa、进气压力为0.36 MPa、预燃室喷油量为6 mg且主燃室喷油量为194 mg时,原机指示热效率可从48.18%提升至48.65%.In order to realize high efficiency and clean combustion on a heavy-duty diesel engine under high load condition,a combustion system disturbed by prechamber jet flow was designed.Its purpose is to use the jet momentum generated in the prechamber to promote the fuel-gas mixing process under high load condition,improve the speed of diffusion combustion and increase isovolumetric degree of combustion,so as to improve the thermal efficiency of the engine.A simulation model of the prechamber was established to study the influence of the action position,duration,momentum,and phase of the prechamber jet on the fuel-gas mixing and combustion.To shorten the combustion duration and improve the indicated thermal efficiency of the engine,the structure of the prechamber was optimized.Based on the simulation results,an experiment platform of the combustion system dis-turbed by prechamber jet flow was established.The experimental results show that the combustion duration under high load can be effectively shortened and the indicated thermal efficiency can be improved without increase of obvious emission.When the speed is 1200r/min,the indicated mean effective pressure(IMEP)is 2.54 MPa,the intake pressure is 0.36 MPa,the injection mass of the prechamber is 6 mg and the injection mass in the main chamber is 194 mg,the indicated thermal efficiency of the engine is increased from 48.18%to 48.65%.

关 键 词：重型柴油机 预燃室 油、气混合 指示热效率 

分 类 号：TK423.2[动力工程及工程热物理—动力机械及工程]