提高发动机性能一致性的公差优化  

Tolerance Optimization for Improvement of Consistency in Engine Performance

作　　者：龚华[1] 许敏[1] 李冕[1] 袁志远[1] 秦际宏 杨晓 

机构地区：[1]上海交通大学汽车电子控制技术国家工程实验室,上海200240 [2]上汽通用五菱股份有限公司,柳州545007

出　　处：《内燃机工程》2015年第6期98-104,共7页Chinese Internal Combustion Engine Engineering

基　　金："十二五"国家科技支撑计划项目(2012BAF06B03);国家自然科学基金项目(51375302)

摘　　要：以一款1.2L排量的四缸汽油机为研究对象,首先搭建了结构尺寸-压缩比的数学计算模型及压缩比-发动机性能仿真模型,并分别进行了试验验证。在此基础上,由发动机性能一致性的要求反推出合理的压缩比波动范围,再运用遗传算法对影响压缩比的关键结构尺寸进行公差优化,最后利用蒙特卡洛模拟方法对优化结果进行分析与验证。研究结果表明:通过公差优化可以将发动机外特性的扭矩波动平均减小了31.7%,燃油消耗率波动平均减小了32.2%。A 4-cylinder gasoline engine with 1. 2 L displacement was used to build a geometrical correlation between the relevant dimensions and the compression ratio, as well as a simulation model between the compression ratio and engine performance using AVL-Boost. Based on those models, the tolerance requirement of the compression ratio was derived from the required engine performance consistency; then the tolerances of the key dimensions influencing the compression ratio was optimized using a genetic algorithm. The Monte-Carlo method, combined with the BOOST simulation, was used to verify the optimization results. The optimized key dimension tolerances can result in a 31.7% reduction in engine torque fluctuation and 32.2% reduction in fuel consumption fluctuation, respectively on average, which improves the engine performance consistency.

关 键 词：内燃机 尺寸公差优化 压缩比 性能一致性 蒙特卡洛模拟 遗传算法 

分 类 号：TK402[动力工程及工程热物理—动力机械及工程]