徐怀民，纪少波，廉静，赵胜晋，程勇

（山东大学 能源与动力工程学院，山东 济南 250061）

    摘要：本文采用3维流体动力学分析软件FIRE对大功率气体机缸内混合气形成过程进行分析。设计了3种不同偏心距的浅盆形活塞,并通过数值解析对比了不同偏心距活塞对缸内混合气形成的影响规律。研究结果表明,相对于其它方案,第三种的活塞缸内湍动能最大,缸内整体混合气形成质量最好,接近压缩上止点时,火花塞附近混合气更为均匀,有利于点火燃烧。通过对不同方案缸内流场分析发现,方案4缸内滚流作用明显,有利的提升了缸内混合气的形成质量。

    关键词：大功率气体机；偏心燃烧室；数值解析；混合形成

Abstract:  Three dimensional hydrodynamic software FIRE was used to analyze mixture formation process of a high power gas engine in this study. Four kinds of shallow basin shaped piston with different eccentricity were designed and the influence of the eccentricity on mixture formation in cylinder was analyzed by numerical analysis. Results showed that compared with the other schemes, the kinetic energy of scheme 4 reached the maximum and the mixture obtained the best quality. When piston was close to the TDC, the gas mixture of scheme 4 near the spark plug was more uniform than others, which would be helpful for the ignition and combustion inside the cylinder. It could be concluded from the analysis of the flow field in different schemes that tumble motion of scheme 4 was more obvious, which could improve quality of the mixture in the cylinder.

Keywords: High Power Gas Engine; Eccentric Chamber; Numerical Analysis; Mixture Formation