高压缩比甲醇发动机非常规排放影响分析  

Analysis of Unregulated Emission for High-Compression Ratio Methanol Engine

作　　者：甄旭东[1] 雷星星 田智 耿杰[1] 李汝宁 李小燕 ZHEN Xudong;LEI Xingxing;TIAN Zhi;GENG Jie;LI Runing;LI Xiaoyan(School of Automotive and Transportation,Tianjin University of Technology and Education,Tianjin 300222,China;State Key Laboratory of Engines,Tianjin University,Tianjin 300072,China;School of Automotive and Transportation Engineering,Hefei University of Technology,Hefei 230009,China)

机构地区：[1]天津职业技术师范大学汽车与交通学院,天津300222 [2]天津大学内燃机燃烧学国家重点实验室,天津300072 [3]合肥工业大学汽车与交通工程学院,安徽合肥230009

出　　处：《车用发动机》2023年第3期52-58,共7页Vehicle Engine

基　　金：国家自然科学基金(51406135)。

摘　　要：采用一维GT-Power和三维CFD仿真软件耦合甲醇氧化详细化学动力学机理,以某传统柴油机参数为基础,搭建了火花点火式甲醇发动机的一、三维物理模型,研究了该甲醇发动机的非常规排放。研究表明:随着负荷的增大,未燃甲醇与甲醛的排放呈现先减少后增多的趋势;小负荷时,增加点火提前角更能有效降低未燃甲醇及甲醛排放;随着转速增加,未燃甲醇排放有增加的趋势,而甲醛排放呈现先增加后减少的趋势;增大EGR率更能明显地降低未燃甲醇及甲醛的排放;压缩比增大可以降低未燃甲醇及甲醛排放,且其增加到17.5之后,排放量几乎接近于0;当压缩比较小时,当量比的增大能有效减少未燃甲醇及甲醛排放;未燃甲醇与甲醛主要分布在缸壁、缸盖底面与活塞顶面的一些缝隙区域。By coupling the detailed chemical kinetic mechanism of methanol oxidation with one-dimensional GT-Power and three-dimensional CFD simulation software,a one-dimensional and three-dimensional physical model of spark ignition methanol engine was established to study the unregulated emissions based on the parameters of a traditional diesel engine.The results show that the emissions of unburned methanol and formaldehyde reduce first and then increase with the increase of load.The emissions of unburned methanol and formaldehyde reduce more effectively by increasing spark advance angle under small loads.With the increase of engine speed,the emissions of unburned methanol increase,while the emissions of formaldehyde increase first and then reduce.The increase of EGR rate reduces the emissions of unburned methanol and formaldehyde significantly.When the compression ratio increases,the emissions also reduce.And when the compression ratio increases to 17.5,the emissions are almost close to 0.In addition,the emissions reduce effectively with the increase of equivalent ratio when the compression ratio is small.The unburned methanol and formaldehyde mainly distribute in the gap areas of cylinder wall,bottom surface of cylinder head and top surface of piston.

关 键 词：高压缩比发动机 甲醇 非常规排放 仿真 

分 类 号：U464.173[机械工程—车辆工程]