DNS of the spatiotemporal evolution of the vorticity in (pure) mode B of a circular cylinder's wake

doi:10.1088/1873-7005/ac4ff6

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-)

	DNS of the spatiotemporal evolution of the vorticity in (pure) mode B of a circular cylinder's wake
	Lin LM(林黎明)3; Tan ZR 1,2
刊名	FLUID DYNAMICS RESEARCH
	2022-02-01
卷号	54 期号:1 页码:23
ISSN号	0169-5983
DOI	10.1088/1873-7005/ac4ff6
英文摘要	In the present paper, the spatio-temporal evolution of the vorticity field in the second wake instability, i.e. (pure) mode B is investigated to understand the wake vortex dynamics and sign relationships among the three vorticity components. Direct numerical simulation of the flow past a circular cylinder in the three-dimensional (3D) wake transition is performed, typically at a Reynolds number of 300. According to the time histories of fluid forces and frequency analysis, three different stages are identified. In the fully developed wake (FDW), the spanwise vortex core is almost two-dimensional, while the vortex braid is 3D due to the dominant streamwise interaction. However, streamwise and vertical vorticities owing to the intrinsic 3D instability are already generated first on cylinder surfaces early in the computational transition (CT). The evolution of additional vorticities with the same features as mode B shows that (pure) mode B could already be formed in the late CT. In the FDW, a special sign symmetry of these additional vorticities on the rear surface is observed, which is exactly opposite to that in (pure) mode B. Similarly, the two sign laws found in (pure) mode A are also verified in three typical regions, independent of the Reynolds number, for (pure) mode B. Particularly, the mechanism for the physical origin of streamwise and vertical vortices in the shear layers is the vortex generation on the wall first and then dominant vortex induction just near the wall. The entire process of the formation and shedding of vortices with three components of vorticity is first and completely illustrated. Other characteristics of the evolution of mode B are presented in detail.
语种	英语
其他责任者	Tan, Z. R.
内容类型	期刊论文
源URL	[http://dspace.imech.ac.cn/handle/311007/88646]
专题	力学研究所_流固耦合系统力学重点实验室(2012-)
作者单位	1.Wuhan Univ Technol, Hubei Key Lab Inland Shipping Technol, Wuhan 430063, Peoples R China 2.Wuhan Univ Technol, Sch Nav, Wuhan 430063, Peoples R China; 3.Chinese Acad Sci, Inst Mech, Key Lab Mech Fluid Solid Coupling Syst, Beijing 100190, Peoples R China;
推荐引用方式 GB/T 7714	Lin LM,Tan ZR. DNS of the spatiotemporal evolution of the vorticity in (pure) mode B of a circular cylinder's wake[J]. FLUID DYNAMICS RESEARCH,2022,54(1):23.
APA	林黎明,&Tan ZR.(2022).DNS of the spatiotemporal evolution of the vorticity in (pure) mode B of a circular cylinder's wake.FLUID DYNAMICS RESEARCH,54(1),23.
MLA	林黎明,et al."DNS of the spatiotemporal evolution of the vorticity in (pure) mode B of a circular cylinder's wake".FLUID DYNAMICS RESEARCH 54.1(2022):23.