摘要
研究了不同条件下概化复式断面的水沙分布规律,定量分析了黄河下游河道斜河产生的机理,结果表明:复式断面滩、槽流速和挟沙力存在较大差异,易引起横向冲淤变化,在一定程度上促进了斜河的发展;河道水、沙量的剧烈变化均能引起河道水深和水面比降的快速变化,导致河道断面流速和挟沙力的显著增大或减小,引起主槽的大量淤积,改变原有的流路形成斜河;对于束窄河段,由于河道断面宽窄相间,且存在滩洲,因此当局部淤积较大时,易引起主流的偏离并形成斜河。
The paper studies the law of silt-discharge distribution of generalized compound cross-section under the different conditions and quantitatively analyzes the mechanism of oblique flow formation of the lower Yellow River.The outcomes show that a) the velocity and sediment carrying force of beach and channel of compound cross-section have great difference and easily cause transverse scour and fill variation,accelerating the development of oblique flow to a certain degree;b) severe variation of channel flow and sediment all can cause sudden changes of water depth and water surface gradient of the channel,resulting in the velocity and sediment carrying force of the channel cross-section remarkably increase or decrease,causing big amount of sedimentation on the main channel,changing the original flow path and forming an oblique flow and;c) when the local deposition is greater,narrowing the section might cause the main flow off the channel and form an oblique flow due to the wide section alternate with narrow ones,in addition to the existed bars and floodplains.
出处
《人民黄河》
CAS
北大核心
2011年第3期13-14,53,共3页
Yellow River
基金
河海大学科研基金资助项目(2009B02414)
关键词
形成机理
斜河
流速分布
挟沙力
黄河下游
formation mechanism
oblique flow
velocity distribution
sediment carrying force
the lower Yellow River
