基于Rouse公式及紊流泥沙沉速公式,分别推导得到了紊流时的悬沙粒径及级配垂线分布公式,前者直接量化了泥沙“上细下粗”的垂线分布规律,后者则可用于计算不同水层及垂线上总的悬沙粒径级配。通过实例,应用粒径级配计算公式得到了不同水层的悬沙粒径级配。结果表明:泥沙粒径“上细下粗”的分布规律明显;在越远离床面的水层,细颗粒所占的比重越大,粒径分布越均匀。当考虑悬浮高度影响时,以最大粒径悬沙的最大悬浮高度为界,该高度之下级配“等宽”,该高度之上级配“上窄下宽”。
Abstract
The vertical distribution formulas of suspended sediments’ particle size and gradation in turbulent flow region are derived respectively based on the Rouse formula and the formula of sediment particle settling velocities in turbulent flow. The former directly quantifies the vertical distribution law of sediment particles being “fine in the upper and coarse in the lower”, while the latter can be used to calculate the suspended sediment’s gradation in different water layers and the total gradation in vertical direction. The formula of particle size distribution is applied to a practical example to calculate the suspended sediment’s gradation in different water layers. Results suggest that the gradation is obviously in the law of “fine in the upper and coarse in the lower”. The farther away from the bed the water layer, the larger the proportion of fine particles, the more uniform the particle size distribution. In consideration of the influence of suspension height, the maximum suspension height of suspended sediments with the largest particle size is taken as the demarcation below which the gradation is in equal width, and above which the gradation distributes narrowly in the lower whereas widely in the upper.
关键词
悬沙粒径级配 /
垂线分布公式 /
Rouse公式 /
相对最大悬浮高度 /
紊流区
Key words
gradation of suspended sediment /
vertical distribution formula /
Rouse formula /
relative maximum suspension height /
turbulent flow region
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参考文献
[1] ROUSE H. Modern Conceptions of the Mechanics of Turbulence[J]. Transactions of the American Society of Civil Engineers, 1937, 102(1): 463-505.
[2] VELIKANOV M A. Alluvial Process[M]. Moscow: State Publishing House for Physical and Mathematical Literature, 1958: 241- 245.
[3] DREW D A. Turbulent Sediment Transport over a Flat Bottom Using Momentum Balance[J]. Journal of Applied Mechanics, 1975,42(1): 38-44.
[4] MCTIGUE D F. Mixture Theory for Suspended Sediment Transport [J]. ASCE, 1981, 107(6): 659-673.
[5] 蔡树棠.相似理论和泥沙的垂直分布[J].应用数学和力学,1982,3(5):605-612.
[6] 邵学军,夏震寰.悬浮颗粒紊动扩散系数的随机分析[J].水利学报,1990,21(10):32-40.
[7] 汪富泉,丁 晶,曹叔尤,等.论悬移质含沙量沿垂线的分布[J].水利学报,1998,29(11):44-49.
[8] 倪晋仁,梁 林.水沙流中的泥沙悬浮[J].泥沙研究,2000(1):7-19.
[9] 赵连军,吴国英,王嘉仪.不平衡输沙含沙量垂线分布理论研究展望[J].水力发电学报,2015,34(4):63-69.
[10]谢葆玲.实验曲线函数关系式的确定[J].泥沙研究,1983(2):64-66.
[11]杨国录,王运辉.实测悬移质级配及分组含沙量修正问题[J].武汉水利电力学院学报,1984,17(4):115-127.
[12]熊治平.河流泥沙级配曲线函数表达式及其检验[J].泥沙研究,1992(2):76-79.
[13]熊治平.悬移质泥沙级配沿垂线分布公式探求[J].武汉水利电力大学学报,1999,32(3):51-54.
[14]侯晖昌.河流动力学基本问题[M].北京:水利出版社,1982:93-102.
[15]张红武.悬移质级配的理论计算[C]∥黄委会水科所科学研究论文集(第1集).郑州:河南科学技术出版社,1989:155-161.
[16]曹志芳.悬移质泥沙级配公式及其应用[J].武汉水利电力大学学报,1996,29(1):115-118.
[17]王延召,张耀哲.有关悬移质级配垂向分布计算方法的改进[J].中国农村水利水电,2018(3):186-189,195.
[18]王昌杰.河流动力学[M].北京:人民交通出版社,2001.
[19]韩其为.非均匀悬移质不平衡输沙[M].北京:科学出版社,2013.
[20]武汉水利电力学院河流泥沙工程学教研室.河流泥沙工程学(上册)[M].北京:水利出版社,1981.
基金
国家重点研发计划项目(2017YFC0405305);财政部三峡工程泥沙重大问题项目(12610100000018J129-5)
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