河流污染物纵向离散系数确定的演算优化法

提出一个确定河流污染物纵向离散系数的新方法——演算优化法。该方法采用示踪剂在两个断面的时间浓度过程数据,将上游断面的实测浓度过程视作下游断面的连续投放源。在下游断面浓度计算值与实测值的平方误差达到最小的条件下,利用优化方法求出河段的平均流速和纵向离散系数。该方法摈弃了传统演算法采用的冻结云团假设,客观地反映了污染物上游浓度变化过程对下游浓度变化过程的影响,同时避免了演算法中繁琐的试算过程。采用Fischer的室内示踪试验数据,对演算优化法与传统演算法进行比较,结果表明演算优化法的计算过程比演算法更快捷,计算出的离散系数更精确可靠。

Routing optimization method for determination of longitudinal dispersion coefficient in river

A new method,namely routing optimization method,for determination of the longitudinal dispersion coefficient in river is suggested.In this method the observed concentration profile at the upstream section is regarded as the continuous source of downstream section and the sum of minimum mean square error of the concentration difference between simulation and observation result is set up as the objective function to utilize the optimization method for obtaining the longitudinal dispersion coefficient and average flow velocity of the river.By using this method the assumption of frozen cloud approximation is no longer be used,the simulation result can objectively reflect the effect of variation process of pollutant concentration at upstream section on downstream section.At the same time the calculation process is simplified.The validity of the method is verified by using the experimental data given by other author.