气候变化领域集成服务门户(CCPortal): The Role of Sand in Wave Boundary Layers Over Primarily Muddy Seabeds: Implications for Wave-Supported Gravity Flows

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DOI	10.1029/2020JC016621
	The Role of Sand in Wave Boundary Layers Over Primarily Muddy Seabeds: Implications for Wave-Supported Gravity Flows
	Han Z.; Horner-Devine A.R.; Ogston A.S.; Hsu T.-J.
发表日期	2021
ISSN	21699275
卷号	126 期号:5
英文摘要	We performed laboratory experiments to investigate the influence of sand content on the dynamics of wave-supported gravity flows in mud-dominant environments. The experiments were carried out in an oscillatory water tunnel with a sediment bed of either 1% or 13% sand. Low and high energy regimes are differentiated based on a Stokes Reynolds number ReΔ ≈ 500. In the low energy regime, the sand fraction influences flow dynamics primarily through ripple formation; no ripples form in the 1% sand experiments, whereas ripples form in the 13% experiments that increase turbulence and the wave boundary layer thickness, δm. In the high energy regime, small ripples form in both the 1% and 13% sand experiments and we observe high near-bed suspended sediment concentrations. The influence of stratification on the boundary layer flow is characterized in terms of the gradient Richardson number Rig. The flow is weakly stratified inside the boundary layer for all runs and critically stratified at or above the top of the boundary layer. In the lower energy regime, the sand content reduces the relative influence of stratification in the boundary layer, shifting the elevation of critical stratification, LB, from approximately 1.3δm to 2.5δm in the 1% and 13% experiments, respectively. In both sets of experiments LB ≈ δm at the strongest wave energy, indicating a transition to strongly stratified dynamics. © 2021. American Geophysical Union. All Rights Reserved.
语种	英语
来源期刊	Journal of Geophysical Research: Oceans
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/186297
作者单位	Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, United States; School of Oceanography, University of Washington, Seattle, WA, United States; Center for Applied Coastal Research, University of Delaware, Newark, DE, United States
推荐引用方式 GB/T 7714	Han Z.,Horner-Devine A.R.,Ogston A.S.,et al. The Role of Sand in Wave Boundary Layers Over Primarily Muddy Seabeds: Implications for Wave-Supported Gravity Flows[J],2021,126(5).
APA	Han Z.,Horner-Devine A.R.,Ogston A.S.,&Hsu T.-J..(2021).The Role of Sand in Wave Boundary Layers Over Primarily Muddy Seabeds: Implications for Wave-Supported Gravity Flows.Journal of Geophysical Research: Oceans,126(5).
MLA	Han Z.,et al."The Role of Sand in Wave Boundary Layers Over Primarily Muddy Seabeds: Implications for Wave-Supported Gravity Flows".Journal of Geophysical Research: Oceans 126.5(2021).