摘要
本文分析总结了在可调坡循环长水槽内进行的冲积床面阻力试验资料,同时分析了国内外其它大量水槽试验及天然冲积河渠的床面形态及阻力资料.结合对冲积床面阻力影响因素的物理分析,总结提出了预报冲积河渠床面阻力的规律及公式,同时提出了区分床面形态低能态和高能态的判别公式,初步搞清和提出了过渡区的阻力关系.根据本文提出的公式,可以计算预报不同水沙条件下长江三峡库区淤积河段、长江中下游、黄河下游及各种冲积河渠的床面阻力.
The investigation of hydraulic resistance of alluvial streams was conducted in a 60-meter recirculating flume at the Sediment Research Laboratory of Tsinghua University in Beijing. A great number of laboratory test results and field data from other investigators have also been analyzed in this paper.The result of study shows that the dimensionless resistance parameter θ* depends not only onθ*' but also on the diameter of the bed material in lower and upper regimes.In transition zone from ripple or dune to flat bed, θ* decreases with the increase of θ*' for a given D and Rb/D and it increases with the increase of Rb/D for given D and θ*'.The friction factor f depends on θ*', D and R/D. f changes with 0^ continuously for given D and Rb/D and decreases with the increase of Rb/D but is maintained constant when Rb/D is larger than 10, 000. Friction factor f decreases in lower regime and increases in upper regime with the increase of D for given θ*'.θ* and θ*' can be computed by the formulae (1 ), (4)-( 7) suggested in this paper. The value of f on sand bed for natural streams can be predicted by formula ( 8 ).
出处
《水利学报》
EI
CSCD
北大核心
1990年第12期18-29,共12页
Journal of Hydraulic Engineering
基金
"三峡二维数学模型"研究基金
