柴油机EGR混合器管路结冰分析与结构优化
李俊琦，石磊，牛鸿斌，闫乐乐，王新校
潍柴动力股份有限公司，山东 潍坊 261061
摘要：为解决某发动机在寒区试验中因废气再循环（exhaust gas recirculation , EGR）混合器管路结冰导致发动机无法起动、动力性能下降等故障，以该发动机进气系统为研究对象，建立进气系统内部流场三维模型，利用STAR-CCM+流体分析软件进行流体仿真（computational fluid dynamics , CFD）计算，结合理论分析，提出EGR混合器布置位置远离进气节流阀、进气加热格栅调整到EGR混合器前和在结冰风险处增加水套结构的优化方案。仿真及寒区试验验证结果表明，改进结构后的发动机可以显著提升各缸的新鲜进气和EGR废气均匀性，避免EGR混合气体在管路内回流，有效解决发动机EGR混合器管路结冰问题。
关键词：柴油机；EGR；寒区结冰；CFD仿真
Analysis of freezing in EGR
pipeline of diesel engine and its structure optimization
LI Junqi, SHI Lei, NIU
Hongbin, YAN Lele, WANG Xinxiao
Weichai Power Co., Ltd.,
Weifang 261061,China
Abstract：In order to solve the engine start failure and
power loss caused by freezing of exhaust gas recirculation (EGR) mixer pipeline
of an engine in cold operation test, three-dimensional flow field model of the
intake system is established by taking the intake system of the engine as the
research object. By using STAR-CCM+ simulation software, the computational
fluid dynamics (CFD) calculation is carried out. Combined with theoretical
analysis, the EGR system is optimized. The EGR mixer is positioned far away
from the intake throttle, the intake heating grate is adjusted in front of the
EGR mixer, water jacket is added at the risk of icing. The results of
simulation and cold operation test show that with the above improvements, the
uniformity of fresh intake air and EGR exhaust gas of each cylinder are
significantly improved, the EGR mixed gas backflow in the pipeline is avoided,
and the problem of icing in the EGR mixer pipeline is effectively solved.
Keywords:diesel engine; EGR; freezing in cold
region; CFD simulation
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