【作者】 于顺东；

【导师】 尤学一；

【作者基本信息】 天津大学 ， 环境科学， 2007， 硕士

【摘要】 随着环境技术的发展,水质模型在环境保护工作中的应用越来越广泛。许多模型的应用需要大量的外部数据,但是有些数据并不容易获得,为减少数据量的需求,国内外进行了大量地研究,例如采用不依赖反应动力学的神经网络方法等,但此类方法大多尚未成熟,远没有动力学模型应用广泛。因此,将现有的反应动力学公式,在精度允许的情况下做相应的简化以达到模拟的要求是本文的主要工作。本文首先总结了水质模型的发展历史以及应用情况,列举了应用广泛的几种水质模型,由于本文模拟对象为流速比较缓慢的平原河流,选用在平原河网模拟中比较成熟的WASP模型作为研究的对象。此模型具有参数输入相对比较灵活的特点,即对同一个模拟的项目可以使用不同复杂程度的动力学公式进行计算。本文将此模型对于水体中溶解氧的计算过程做了比较详细的介绍,对模型可以使用的各种不同数据量要求的溶解氧计算所包含的过程以及计算公式进行了分析和比较。本文使用WASP模型模拟了Brandywine河流1999年全年的水质变化情况,并将模拟结果与实测结果进行了比较,模拟预测的数据和实测数据符合的很好。本文还对敏感度比较高的模型参数如水温、流量Q、20℃CBOD衰减系数等进行了敏感度分析,得出水温是敏感度最高参数的结论。进一步使用四种不同复杂度的水体溶解氧公式进行模拟,并将模拟结果与实测值进行比较,显示使用改进的Streeter-Phelps方程可以满足此次模拟河流溶解氧变化的需要。本文还发现河流上游的堤坝对溶解氧浓度的影响很小。最后,使用改进的Streeter-Phelps方程对2006年汤河流经市区一段水体的水质进行了模拟验证,预测了本段河流在2006年6～8月份的水质,结果反映了水质情况。结果证实了WASP水质模型可以用于平原河流水质模拟。更多还原

【Abstract】 The application of water quality model in environmental protection becomes more and more important with the development of environmental technology. Some models require large amounts of external data, which are not easily accessed. To reduce the data requirement, many methods have been proposed such as the neural network method. But many of such kinds of methods are not mature enough to replace the kinetic models applied widely. The main work of this dissertation is to simplify kinetic formulas to reach the requirement of data reduced.The development and application of the water quality models are summarized. The WASP model is chosen in this approach because the rivers studied here are plain rivers where the flow velocity is low. Although this model has a lot of successful applications, it is still lack at evaluating its model parameters and optimizing DO models. The four DO models are compared in this approach.The water quality of the Brandywine River in 1999 is simulated with the WASP model. The results show good agreements with the field observation data. The sensitivity analysis for the selected model parameters such as temperature, flux, CBOD decay rate at 20℃, etc. is studied. It is found that the water temperature is the most sensitive coefficient. Four water dissolved oxygen formula with different complexity are compared in detail. The result shows that modified Streeter-Phelps equations meet the need of WASP water quality simulation. The effects of the dam on DO are found small.The water quality of Tang River, which goes through the urban of Qinhuangdao city, is selected to be simulated. The change of water quality of Tang River from June to August in 2006 is forecast by applying WASP model with the modified Streeter-Phelps equations. The results show good performances of WASP model.更多还原