某船用柴油机各缸排温不均匀性优化设计

王任信¹，张万枝¹，李玉贺¹，李成¹，马超²，凌健³

1.广西玉柴机器股份有限公司技术研究院,广西 南宁  530000；

2.康跃科技（山东）有限公司，山东 寿光  262711；3.中汽研汽车检验中心(天津)有限公司，天津  300000

摘要：为优化某船用柴油机各缸排温均匀性，设计定压增压、气门正时优化技术方案和气门正时优化配合改进型MFB2凸轮型线方案，对原柴油机和各优化方案进行热力学仿真分析，对改进凸轮型线发动机进行台架试验测试。结果表明：定压增压方案可显著改善各缸排温不均匀性，标定点各缸排温极差降低至19 ℃，但比油耗恶化显著,最大上升3.5 g/(kW·h)；气门正时优化配合改进型MFB2凸轮型线算法方案可显著改善各缸排温的不均匀性，标定点各缸排温极差降低至31 ℃，且该方案对比油耗的影响较小；试验验证表明各缸排温差异为34 ℃，油耗与原机基本相同；仿真分析与试验测试结果吻合较好。本研究可为柴油机各缸排温不均匀性优化提供参考。

关键词：柴油机；排温均匀性；定压增压；气门正时；优化

Optimization design of the non-uniform exhaust temperature for a marine diesel engine

WANG Renxin¹, ZHANG Wanzhi¹, LI Yuhe¹, LI Cheng¹, MA Chao², LING Jian³

1.Technical Institute,Guangxi Yuchai Machinery Co.,Ltd.,Nanning  530000,China;

2.Kangyue Technology (Shandong) Co., Ltd., Shouguang  262718, China;

3. CATARC Automotive Test Center (Tianjin) Co., Ltd., Tianjin  300000, China

Abstract： In order to optimize the non-uniform exhaust temperature of the cylinders, two technical routes are analyzed using 1D thermodynamic simulation method. One is using constant pressure turbocharger,the other is valve timing optimization. The bench test is carried out using the diesel engine with the valve timing optimization cooperated with MFB2 combined compound sine cam profile and original diesel engine. The results show that the constant pressure turbocharger method can get a very good distribution on exhaust temperature of the cylinders.For rated speed operation, the difference of each temperature is 19 ℃. But it increases the brake specific fuel consumption (BSFC) significantly (max value is 3.5 g/(kW·h)). Valve timing optimization cooperated with MFB2 combined compound sine cam profile also get a very good distribution on each temperature. For rated speed operation, the difference of each cylinder′s temperature is 31 ℃ ,and it has little impact on the BSFC. The test result shows that the simulation analysis is in good agreement with the experimental results,the difference of each temperature is 34 ℃ and BSFC is nearly the same as the original diesel. The research could give a reference to the optimization of non-uniform exhaust temperature.

Keywords:diesel engine; non-uniform exhaust temperature;constant pressure supercharging;valve timing; optimization