摘要
横向扩散系数是衡量水流对污染物质混合输移能力的重要参数之一，在水污染控制方面具有重要作用。本文通过理论分析及对水槽实验结果的综合研究，提出平直光滑矩形槽中横向紊动扩散系数的理论公式为：Ｄ＿ｙ＝０．３１ｕ￣２／ω。因式中的ω表示基本脉动流速的统计频率，实际应用时尚难以简单确定，所以进一步运用量纲分析并汇总国外发表的较权威的矩形明渠试验数据，得出横向扩散系数的实用计算公式为：Ｄ＿ｙ＝αｈｕ，其中α＝０．０６２（Ｗ／ｈ）￣（０．２７７）。从而充实了该方面的研究成果。
Transverse diffusion coefficient that plays an important role in water pollution control,isone of the governing coefficients for measuring the mixing and transport capacity of pollutantsdriven by flow,Based on the theoretical analysis and the synthetical study of open channel experi-ments,the theoretical formula of transverse turbulent diffusion coefficient in flat straight smoothand rectangular open channels is obtained in the paper as:D_y=0. 31u￣2/ω However,in the for-mula stands for the statistical frequency of fundamental pulse velosity,and is difficult to be deter-mined in calculating process. By means of dimension analysis and summarizing the internationalauthoritative experiment reports about rectangular open channels,a further usable calculativeformula of transverse diffusion coefficient is derived with the form as D_y=αhu_*,where α=0. 062(W/h)￣(0.277) which has substantiated the results in this research area.
出处
《甘肃科学学报》
1995年第2期8-12,共5页
Journal of Gansu Sciences
关键词
紊动扩散
横向扩散系数
水质污染
Water pollution
Turhulent diffusion
Transverse diffusion coefficient
