Global S&T Development Trend Analysis Platform of Resources and Environment
DOI | 10.1002/2017WR020883 |
Direct measurements of lift and drag on shallowly submerged cobbles in steep streams: Implications for flow resistance and sediment transport | |
Lamb, Michael P.; Brun, Fanny; Fuller, Brian M. | |
2017-09-01 | |
发表期刊 | WATER RESOURCES RESEARCH
![]() |
ISSN | 0043-1397 |
EISSN | 1944-7973 |
出版年 | 2017 |
卷号 | 53期号:9 |
文章类型 | Article |
语种 | 英语 |
国家 | USA |
英文摘要 | Steep mountain streams have higher resistance to flow and lower sediment transport rates than expected by comparison with low gradient rivers, and often these differences are attributed to reduced near-bed flow velocities and stresses associated with form drag on channel forms and immobile boulders. However, few studies have directly measured drag and lift forces acting on bed sediment for shallow flows over coarse sediment, which ultimately control sediment transport rates and grain-scale flow resistance. Here we report on particle lift and drag force measurements in flume experiments using a planar, fixed cobble bed over a wide range of channel slopes (0.004 Plain Language Abstract Steep mountain streams have slower flow and they transport less sediment as compared to lower gradient rivers. Often these observations are attributed to complex river-bed geometries, but little work has explored steep rivers with simple, flat riverbeds. To address this gap in observations, we performed a series of experiments in a controlled indoor river facility and measured directly the forces that flowing water imparts on streambed cobbles and boulders. Under the shallow, rough water flows common to mountain streams, we found that downstream oriented drag forces significantly increase in shallow flow. On the contrary, vertically oriented forces pull the cobbles towards the river bed, rather than the more common scenario where they lift sediment off the bed. We also observed a lower intensity of turbulence in steep rivers, despite the vigorous appearance of the water. Combined, these observations help to explain reduced water flow and sediment transport rates in mountain rivers. |
英文关键词 | drag lift flow resistance friction coefficient sediment transport |
领域 | 资源环境 |
收录类别 | SCI-E |
WOS记录号 | WOS:000413484200007 |
WOS关键词 | BED-LOAD TRANSPORT ; HYDRAULIC ROUGHNESS ; BEDLOAD TRANSPORT ; TURBULENT-FLOW ; GRAVEL ; MOTION ; FORCES ; RIVER ; GRAIN ; CHANNELS |
WOS类目 | Environmental Sciences ; Limnology ; Water Resources |
WOS研究方向 | Environmental Sciences & Ecology ; Marine & Freshwater Biology ; Water Resources |
引用统计 | |
文献类型 | 期刊论文 |
条目标识符 | http://119.78.100.173/C666/handle/2XK7JSWQ/19967 |
专题 | 资源环境科学 |
作者单位 | CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 USA |
推荐引用方式 GB/T 7714 | Lamb, Michael P.,Brun, Fanny,Fuller, Brian M.. Direct measurements of lift and drag on shallowly submerged cobbles in steep streams: Implications for flow resistance and sediment transport[J]. WATER RESOURCES RESEARCH,2017,53(9). |
APA | Lamb, Michael P.,Brun, Fanny,&Fuller, Brian M..(2017).Direct measurements of lift and drag on shallowly submerged cobbles in steep streams: Implications for flow resistance and sediment transport.WATER RESOURCES RESEARCH,53(9). |
MLA | Lamb, Michael P.,et al."Direct measurements of lift and drag on shallowly submerged cobbles in steep streams: Implications for flow resistance and sediment transport".WATER RESOURCES RESEARCH 53.9(2017). |
条目包含的文件 | 条目无相关文件。 |
除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。
修改评论