DOI: 10.1002/2017JF004398
Scopus记录号: 2-s2.0-85043396827
论文题名: Direct Numerical Simulation of Transverse Ripples: 1. Pattern Initiation and Bedform Interactions
作者: Zgheib N. ; Fedele J.J. ; Hoyal D.C.J.D. ; Perillo M.M. ; Balachandar S.
刊名: Journal of Geophysical Research: Earth Surface
ISSN: 21699003
出版年: 2018
卷: 123, 期: 3 起始页码: 448
结束页码: 477
语种: 英语
英文关键词: bedform interactions
; coupled bed-flow simulation
; direct numerical simulation
; pattern formation
; ripples
; self-similarity
Scopus关键词: bedform
; computer simulation
; flow field
; flow pattern
; landform evolution
; Reynolds number
; ripple
; spatiotemporal analysis
; vorticity
英文摘要: We present results of coupled direct numerical simulations between flow and a deformable bed in a horizontally periodic, turbulent open channel at a shear Reynolds number of Reτ = 180. The feedback between the temporally and spatially evolving bed and the flow is enforced via the immersed boundary method. Using the near-bed flow field, we provide evidence on the role of locally intense near-bed vortical structures during the early stages of bed formation, from the emergence of quasi-streamwise streaks to the formation of incipient bedform crestlines. Additionally, we take a new look at a number of defect-related bedform interactions, including lateral linking, defect and bedform repulsion, merging, and defect creation, and show that the underlying mechanisms, in these flow-aligned interactions, are very similar to each other. Consequently, the interactions are labeled differently depending on the geometry of interacting structures and the outcome of the interaction. In the companion paper, we compare our results to published experimental data and provide an extensive quantitative analysis of the bed, where we demonstrate the importance of neighboring structures, especially upstream neighbors, on bedform dynamics (growth/decay and speed) and wave coarsening. Video files of bed evolution are available in the supporting information. ©2018. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/114295
Appears in Collections: 气候减缓与适应
There are no files associated with this item.
作者单位: Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, FL, United States; School of Engineering, Lebanese American University, Byblos, Lebanon; ExxonMobil Upstream Research Company, Houston, TX, United States
Recommended Citation:
Zgheib N.,Fedele J.J.,Hoyal D.C.J.D.,et al. Direct Numerical Simulation of Transverse Ripples: 1. Pattern Initiation and Bedform Interactions[J]. Journal of Geophysical Research: Earth Surface,2018-01-01,123(3)