严寒地区库水温计算经验公式对比及修正

Comparison and modification of empirical formulas for calculation of water temperature in reservoirs in cold region

本文选取严寒地区3座典型水库作为研究对象,分别采用朱伯芳法和统计分析法计算水库坝前水温,并与实测数据进行对比。结果表明:在冬季,统计分析法计算结果优于朱伯芳法;夏季两种经验公式计算结果与实测值均比较接近;秋冬季节,两种经验公式均不能模拟由不稳定分层引起的掺混现象。整体而言,统计分析法优于朱伯芳法,但仍需进一步修正。在分析统计分析法计算偏差原因的基础上,本文提出了基于统计分析法的水体垂向掺混修正计算的方法和具体步骤,修正结果与实测值吻合良好。经修正,统计分析法更适用于严寒地区水库坝前水温计算。研究成果对混凝土坝温控设计及运行管理具有重要参考价值。

Reservoir water temperature has been calculated using Zhu Bofang＇s method and statistical analysis method and compared with the measured temperature in the case studies of three typical reservoirs in cold region. The results show that for the water temperature in winter, the statistical analysis method is better while in summer, the results of both methods are close to the measurements. For the autumn and winter seasons, neither of these empirical formulas can take into account the mixing phenomenon driven by instable stratification. Overall, the statistical method, though better than Zhu Bofang＇s method, still needs further modification. We have examined the causes for its deviations in temperature calculation and developed a correction method and corresponding procedure for calculation of the effects of vertical mixing in large water bodies. The corrected results are in good agreement with the measured temperature. The statistical analysis method after correction shows a better accuracy in calculation of the water temperature in reservoirs in cold region. The results would help temperature control design and operation management of concrete dams.