柴油/天然气发动机燃烧系统协同优化方法

采用KIVA-3V软件耦合多目标遗传优化算法NSGA-3,开展了柴油/天然气双燃料发动机的引燃柴油喷射参数、运行参数和燃烧室结构参数的协同优化研究.将湍流火焰速度封闭模型(TFSC)与PaSR燃烧模型耦合,建立柴油/天然气双燃料发动机复合燃烧模型.结果表明:复合燃烧模型能较好地模拟柴油/天然气发动机的燃烧过程;采用KIVA3V-NSGA3程序进行了双燃料发动机运行参数、喷射参数等多目标参数的协同优化;多目标参数优化结果的数据对比分析揭示了设计参数对目标参数的影响规律;涡流比和喷射参数的变化会对燃烧室内温度、NOx和CH4的分布产生较大影响.

Collaborative Optimization of a Diesel/Natural Gas Engine Combustion System

KIVA-3V software coupled with multi-objective genetic optimization algorithm of NSGA-3 was used to carry out collaborative optimization of diesel pilot injection parameters,engine operating parameters and combustion chamber design parameters for a diesel/natural gas dual fuel engine. The turbulent flame speed closed model(TFSC) was coupled with the Pa SR combustion model to establish a composite combustion model for the dual fuel engine. The results show that the composite combustion model can better simulate the combustion process of the diesel/natural gas dual fuel engine. Multi-objective parameters of the dual fuel engine operating parameters and the injection parameters were optimized by the KIVA3V-NSGA3 program. The multi-objective parameter optimization results show the effect of the design parameters on the target parameters. The value of swirl ratio and the change of injection parameters is found to have great influences on the combustion temperature and the distribution of NOx and CH4 in the combustion chamber.