三维自由射流缩流及扩散的数值研究  

NUMERICAL RESEARCH ON CONTRACTION AND EXPANSION OF 3-D FREE WATER JET

作　　者：韩凤琴[1] 周晶林[1] 吴迪[1] 黄乐平[1] 久保田乔[1] 

机构地区：[1]华南理工大学电力学院,广东广州510640

出　　处：《工程热物理学报》2008年第8期1323-1326,共4页Journal of Engineering Thermophysics

基　　金：国家自然科学基金项目(No.50679027)

摘　　要：由于非定常多相流特性,大气下水自由射流的水力性能相当复杂。本文依据弯管二次流机理确定的最优湍流模型,以六喷嘴冲击式水轮机最末端的喷嘴射流作为研究对象,进行了三维非定常自由射流的数值模拟解析。定量分析了三维自由射流在不同空间方向沿程变化的两相流流态、能量构造及射流形状,为水斗提供了真实的入流条件,确认了最末端喷嘴射流水力效率较差的原因:由于最末端喷管的急剧弯道使得射流产生了大幅度的膨胀扩散。The hydraulic performance of free water jet under air is complicated due to the complex unsteady multiphase flow.After confirming the optimum turbulence model with the mechanism of secondary flow in bend,the 3D numerical simulation for unsteady free water jet was finished by using the jet flow for the last nozzle of 6-nozzle vertical Pelton turbine.The energy distributions and the flow pattern of two-phase water jet which transformed along the flow were quantitatively analysed, then the real inlet condition...

关 键 词：多喷嘴冲击式水轮机 自由射流 三维数值仿真 弯管二次流 缩流及扩散 

分 类 号：TK730[交通运输工程—轮机工程]