Numerical analysis of two distinct types of vortex dislocation in wake-type flows with different spanwise nonuniformities

IMECH-IR > 力学所知识产出(1956-2008)

	Numerical analysis of two distinct types of vortex dislocation in wake-type flows with different spanwise nonuniformities
	Ling GC(凌国灿); Niu JY(牛家玉)
会议录名称	3rd M.I.T. Conference on Computational Fluid and Solid Mechanics
	2005
会议名称	3rd M.I.T. Conference on Computational Fluid and Solid Mechanics
会议日期	June 14, 2005 - June 17, 2005
会议地点	Boston, MA, United states
摘要	Two distinct types of vortex dislocation generated in wake-type flows with different spanwise nonuniformities are numerically studied by direct numerical simulation (DNS). A local spanwise disturbance to the velocity of the oncoming flow leads to a generation of consecutive twisted vortex dislocations in the middle downstream, which is mainly caused by phase differences among vortex-shedding cells. A stepped variation of velocity in the oncoming flow yields a periodic vortex splitting-reconnection type of dislocation, which is mainly caused by frequency differences among the shedding cells. Dynamics and main features of these dislocations, especially the vortex linkages over the dislocations, are clearly described by tracing the substantial modification of vorticity lines and other key flow quantities. Local irregularities in the variations of velocity, vorticity and frequency, and transition behavior of the wake flows are analyzed by wavelet analysis and the proper orthogonal decomposition (POD) method. © 2005 Elsevier Ltd.
关键词	Flow Quantities Frequency Differences Local Irregularities Non-uniformities Phase Difference Proper Orthogonal Decomposition Method Transition Behavior Vortex Dislocation Vortex Dislocations Wake Flows Wake-type Flow
ISBN号	080444814
收录类别	EI
语种	英语
文献类型	会议论文
条目标识符	http://dspace.imech.ac.cn/handle/311007/60284
专题	力学所知识产出(1956-2008)
推荐引用方式 GB/T 7714	Ling GC,Niu JY. Numerical analysis of two distinct types of vortex dislocation in wake-type flows with different spanwise nonuniformities[C]3rd M.I.T. Conference on Computational Fluid and Solid Mechanics,2005.