摘要
根据尼古拉兹实验结果拟合得到一个新的掺混长度表达式。将新掺混长度表达式与对数流速梯度相结合,得到动量传递系数的表达式。在此基础上假定泥沙紊动扩散系数与对应的动量传递系数相等,进而得到新的含沙量垂线分布公式。该公式与Rouse公式、van Rijn公式以及张瑞瑾公式相比,精度十分近似,有效地解决了Rouse公式表层含沙量为零,van Rijn公式分段表述结构不统一,以及张瑞瑾公式结构过于复杂的缺陷。利用多个海域实测资料对其进行验证,验证结果表明,新的含沙量垂线分布公式能够较客观地反映含沙量垂线分布规律。
According to the Nikuradse experimental results, a new mixing length formula was fitted. Combining the new mixing length expressions with logarithmic velocity gradient, the expression of momentum transfer coefficient was obtained. On this basis, sediment turbulent diffusion coefficient was assumed to be equal to the momentum transfer coefficient, and a new vertical distribution formula of suspended sediment concentration was derived. Under the comparison with Rouse formula, van Rijn formula and Zhang rui-jin formula, the accuracy is approximate. Meanwhile, it improves the problem of zero sediment concentration at surface in Rouse formula, the problem of segmented representation in van Rijn formula, and the problem of complicated structure in Zhang rui-jin formula. According to the verification of observation data, the new formula can objectively reflect the vertical distribution law of sediment concentration.
出处
《水道港口》
2014年第1期38-42,共5页
Journal of Waterway and Harbor
关键词
掺混长度
紊动扩散系数
含沙量垂线分布
mixing length
turbulent diffusion coefficient
sediment vertical distribution
