Helical-wave decomposition and applications to channel turbulence with   streamwise rotation

doi:10.1017/S0022112010003071

CORC > 北京大学 > 工学院

	Helical-wave decomposition and applications to channel turbulence with streamwise rotation
	Yang, Y.T. ; Su, W.D. ; Wu, J.Z.
刊名	journal of fluid mechanics
	2010
关键词	rotating turbulence turbulence simulation turbulence theory LOW-REYNOLDS-NUMBER 3-DIMENSIONAL TURBULENCE SYSTEM ROTATION HOMOGENEOUS TURBULENCE DIRECT SIMULATIONS INERTIAL WAVES ROSSBY NUMBER FLOW ENERGY APPROXIMATION
DOI	10.1017/S0022112010003071
英文摘要	Using helical-wave decomposition (HWD), a solenoidal vector field can be decomposed into helical modes with different wavenumbers and polarities. Here, we first review the general formulation of HWD in an arbitrary single-connected domain, along with some new development. We then apply the theory to a viscous incompressible turbulent channel flow with system rotation, including a derivation of helical bases for a channel domain. By these helical bases, we construct the inviscid inertial-wave (IW) solutions in a rotating channel and derive their existing condition. The condition determines the specific wavenumber and polarity of the IW. For a set of channel turbulent flows rotating about a streamwise axis, this channel-domain HWD is used to decompose the flow data obtained by direct numerical simulation. The numerical results indicate that the streamwise rotation induces a polarity-asymmetry and concentrates the fluctuating energy to particular helical modes. At large rotation rates, the energy spectra of opposite polarities exhibit different scaling laws. The nonlinear energy transfer between different helical modes is also discussed. Further investigation reveals that the IWs do exist when the streamwise rotation is strong enough, for which the theoretical predictions and numerical results are in perfect agreement in the core region. The wavenumber and polarity of the IW coincide with that of the most energetic helical modes in the energy spectra. The flow visualizations show that away from the channel walls, the small vortical structures are clustered to form very long columns, which move in the wall-parallel plane and serve as the carrier of the IW. These discoveries also help clarify certain puzzling problems raised in previous studies of streamwise-rotating channel turbulence.; http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000283960400005&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701 ; Mechanics; Physics, Fluids & Plasmas; SCI(E); EI; 7; ARTICLE; 91-122; 662
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/316050]
专题	工学院
推荐引用方式 GB/T 7714	Yang, Y.T.,Su, W.D.,Wu, J.Z.. Helical-wave decomposition and applications to channel turbulence with streamwise rotation[J]. journal of fluid mechanics,2010.
APA	Yang, Y.T.,Su, W.D.,&Wu, J.Z..(2010).Helical-wave decomposition and applications to channel turbulence with streamwise rotation.journal of fluid mechanics.
MLA	Yang, Y.T.,et al."Helical-wave decomposition and applications to channel turbulence with streamwise rotation".journal of fluid mechanics (2010).