Spanwise phase transition between pure modes A and B in a circular cylinder’s wake. Part II: spatiotemporal evolution of vorticity

doi:10.1088/1873-7005/ad02ba

CORC > 力学研究所 > 中国科学院力学研究所 > 流固耦合系统力学重点实验室(2012-)

	Spanwise phase transition between pure modes A and B in a circular cylinder’s wake. Part II: spatiotemporal evolution of vorticity
	Lin,L M
刊名	Fluid Dynamics Research
	2023-10-01
卷号	55 期号:5
关键词	spanwise phase transition wake circular cylinder mode A mode B
ISSN号	0169-5983
DOI	10.1088/1873-7005/ad02ba
通讯作者	Lin,L M()
英文摘要	Abstract Through direct numerical simulation, the transition from pure mode A to mode B in the near wake of a circular cylinder is studied without consideration of vortex dislocations. The Reynolds number R e is calculated from 100 to 330 with a computational spanwise length of 4 diameters. In the present section, the spatiotemporal evolution of the vorticity and its sign are analyzed. The results show that mode B, as a kind of weak disturbed vorticity with opposite signs, actually appears partially on the rear surface of the cylinder and in the shear layers once Re exceeds 193. With increasing R e , the vortex-shedding patterns in the near wake undergo the initial generation stage of mode B coupling with the fully developed pure mode A ( 193 ? R e < 230 ), the mode swapping or coexistence stage between modes A and B ( 230 ? R e < 260 ～ 265 ), the self-adjustment stage of the nondimensional spanwise wavelength from 0.8 to 1 in dominant mode B ( 260 ～ 265 ? R e < 310 ), and the full development stage of mode B ( R e ? 310 ). In particular, the spanwise phase transition initially occurs at a certain spanwise position in the initial generation stage where a part of mode A and a part of mode B with specific vorticity signs appear, e.g. the Π ? vortex in mode A and the Π + vortex in mode B, in which Π ? and Π + vortices are vortices with three vorticity components satisfying the vorticity sign law and shed from the upper and lower shear layers, respectively.
语种	英语
WOS记录号	IOP:FDR_55_5_055505
内容类型	期刊论文
源URL	[http://dspace.imech.ac.cn/handle/311007/93309]
专题	力学研究所_流固耦合系统力学重点实验室(2012-)
通讯作者	Lin,L M
作者单位	Key Laboratory for Mechanics in Fluid Solid Coupling Systems, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China
推荐引用方式 GB/T 7714	Lin,L M. Spanwise phase transition between pure modes A and B in a circular cylinder’s wake. Part II: spatiotemporal evolution of vorticity[J]. Fluid Dynamics Research,2023,55(5).
APA	Lin,L M.(2023).Spanwise phase transition between pure modes A and B in a circular cylinder’s wake. Part II: spatiotemporal evolution of vorticity.Fluid Dynamics Research,55(5).
MLA	Lin,L M."Spanwise phase transition between pure modes A and B in a circular cylinder’s wake. Part II: spatiotemporal evolution of vorticity".Fluid Dynamics Research 55.5(2023).