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 页码:36
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.(llmbirthday@163.com)
英文摘要	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 Re 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 Re, 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 <= Re < 230), the mode swapping or coexistence stage between modes A and B (230 <= Re < 260 similar to 265), the self adjustment stage of the nondimensional spanwise wavelength from 0.8 to 1 in dominant mode B (260 similar to 265 <= Re < 310), and the full development stage of mode B (Re >= 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 Pi(-) vortex in mode A and the Pi(+) vortex in mode B, in which Pi- and Pi+ vortices are vortices with three vorticity components satisfying the vorticity sign law and shed from the upper and lower shear layers, respectively.
资助项目	The authors wish to thank the Hainan Province Science and Technology Special Fund (ZDYF2022GXJS004, ZDYF2021GXJS028) for this work.[ZDYF2022GXJS004] ; The authors wish to thank the Hainan Province Science and Technology Special Fund (ZDYF2022GXJS004, ZDYF2021GXJS028) for this work.[ZDYF2021GXJS028] ; Hainan Province Science and Technology Special Fund
WOS关键词	BOUNDARY-LAYER SEPARATION ; NUMERICAL-SIMULATION ; PHYSICAL-MECHANISM ; INITIAL-STAGE ; SQUARE ; FLOW ; VORTEX ; DYNAMICS ; INSTABILITY ; TURBULENCE
WOS研究方向	Mechanics ; Physics
语种	英语
WOS记录号	WOS:001099438000001
资助机构	The authors wish to thank the Hainan Province Science and Technology Special Fund (ZDYF2022GXJS004, ZDYF2021GXJS028) for this work. ; Hainan Province Science and Technology Special Fund
内容类型	期刊论文
源URL	[http://dspace.imech.ac.cn/handle/311007/93405]
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	Chinese Acad Sci, Key Lab Mech Fluid Solid Coupling Syst, Inst Mech, Beijing 100190, Peoples R 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):36.
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),36.
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):36.