【摘要】 HCCI燃烧过程多维数值模拟十分耗时。采用并行计算和简化机理对HCCI燃烧过程多维CFD模拟计算进行了加速对比。研究基于16-CPU计算机集群系统,采用消息传递的并行算法(M essage-Passing Interface,MPI)方式计算。结果表明,内燃机HCCI燃烧多维燃烧模拟,采用8个CPU能获得最大收益:纯流动计算加速5倍,耦合化学反应流动计算加速4倍,简化反应机理又可加速9倍。通过优化选择并行计算CPU数量和反应机理,使得HCCI发动机单个循环模拟时间由一个月缩短到一天,大大提高了汽车发动机燃烧模拟计算的效率。而且采用三维CFD耦合化学反应的模拟计算,可以解析HCCI发动机着火燃烧过程,提供详细的流动、燃烧和排放物生成的瞬态信息。更多还原

【Abstract】 This study improved the computational efficiency significantly by using the parallel computation and reduced mechanisms.The simulations were made under a cluster of 16-CPU,parallelized using message-passing interface(MPI) mode.The cases with detailed and reduced reaction mechanisms were calculated using 1,2,4,8,16 CPUs respectively and the corresponding computational time and time-reduced were discussed.Using MPI 8-CPU with the reduced mechanism can obtain the best results for CFD/Chemistry calculation of a typical HCCI engine.For the whole HCCI engine simulation,the calculation time reduced from 1 month to 1 day from using single CPU with detailed mechanism to MPI 8-CPU with reduced mechanism.Moreover,CFD/Chemistry calculation can provide the detailed insight to ignition,combustion and pollution formation processes of HCCI engines.更多还原