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通过修改发动机多维CFD计算程序KIVA-3V,建立了内燃机缸内冷态流场的大涡模拟(LES)计算模型。利用此模型对二气门汽油机进气与压缩过程中缸内流场进行了详细分析,并与κ-ε、RNGκ-ε模型进行了比较。结果表明与采用κ-ε、RNGκ-ε模型计算时相比,采用LES计算时显示了更为复杂的湍流结构。同时,采用LES计算时除能得到有序的大尺度涡团结构外,还能捕捉到大量不规则的小涡团结构,而采用κ-ε、RNGκ-ε模型进行计算时,基本上捕捉不到不规则的小涡团结构。
The large eddy simulation (LES) calculation model of the cold flow field in the internal combustion engine is established by modifying the KIVA-3V engine multi-dimensional CFD calculation program. Using this model, the in-cylinder flow field during intake and compression of a two-valve gasoline engine was analyzed in detail and compared with the κ-ε and RNGκ-ε models. The results show that LES calculation shows a more complex turbulent structure than when using κ-ε and RNGκ-ε models. At the same time, a large number of irregular small vortical structures can be captured by using LES in addition to the ordered large-scale vortex structures. However, when using the κ-ε and RNGκ-ε models, they basically capture To the irregular small vortex structure.