某16缸发动机排温不均匀性分析及优化
张健健1，2，王孝丽1，2，刘臻1，2，马超1，3，王丹妮1，2
1.康跃科技（山东）有限公司，山东寿光262718；
2.机械工业内燃机增压系统重点实验室，山东寿光262718；
3.潍坊学院机械与自动化学院，山东潍坊261061
摘要：为解决某16缸发电用柴油机各缸排温不均匀性问题，建立一维热力学模型，仿真分析各缸不均匀性原因，设计使用中间管和定压排气管方案使各缸排气背压一致，改善各缸排温不均匀性，并进一步优化定压管方案。仿真计算表明：柴油机发火顺序和脉冲排气管设计导致各缸排气干涉是各缸排温不均匀的主要原因；中间管方案可以改善各缸排气的相互影响，各缸平均排温极差比原方案降低约28%；定压排气管方案可以改善各缸排气背压不均匀性，各缸平均排温极差比原方案降低约40%；随着定压管总管径的增加，发动机比油耗先减小后增大；采用定压排气管优化方案后的发动机各项指标与原机基本一致，各缸的排温极差降低40%以上，有效改善了各缸排温的不均匀性。
关键词：排温不均匀性；脉冲排气管；定压排气管；排气干涉；比油耗
Analysis and optimization of a 16-cylinder engine with non-uniform exhaust temperature
ZHANG Jianjian1,2, WANG Xiaoli1,2, LIU Zhen1,2, MA Chao1,3, WANG Danni1,2
1.Kangyue Technology (Shandong) Co., Ltd., Shouguang 262718,China;
2.Key Laboratory of Turbocharging System of Machinery Industry, Shouguang 262718,China;
3.School of Mechanical and Automation, Weifang University, Weifang 261061,China
Abstract：In order to solve the problem of non-uniform exhaust temperature of each cylinder of a 16-cylinder diesel engine, a one-dimensional thermodynamic model is established to simulate and analyze the causes of non-uniformity of each cylinder. An optimization strategy is proposed to use the intermediate pipe and the constant pressure exhaust pipe to reduce the non-uniform of the exhaust back pressure and improve the distribution of the exhaust temperature of each cylinder. The constant pressure pipe scheme has been further optimized. The result of simulation calculation shows that the main reason for the non-uniform exhaust temperature is the interference of the exhaust gas of each cylinder caused by the firing sequence of the diesel engine and the design of the pulse exhaust pipe. The use of the intermediate pipe scheme can improve the mutual influence of the exhaust gas of each cylinder, and the extreme difference of the exhaust temperature of each cylinder is reduced by about 28% compared with the original scheme. The constant pressure exhaust pipe scheme can reduce the non-uniformity of exhaust back pressure of each cylinder, and the exhaust temperature range of each cylinder is reduced by about 40% compared with the original scheme. With the increasing of the total pipe diameter of the constant pressure pipe, the specific fuel consumption of the engine firstly decreases and then increases. The optimized constant pressure exhaust pipe scheme shows that the various indicators of the engine are nearly the same as the original engine, and the exhaust temperature range of each cylinder is reduced by more than 40%, which effectively reduces the non-uniform of exhaust temperature of each cylinder.
Keywords:non-uniformity of exhaust temperature；pulse exhaust pipe；constant pressure exhaust pipe；exhaust interference；specific fuel consumption
