为预报钱塘江河口取水口水体氯度,应用基于Godunov 格式的有限体积法建立了考虑涌潮作用的二维氯度预报数值模型,采用实测资料并结合数值模型计算成果,分析了径流、潮汐及涌潮、江道地形等主要因素对钱塘江河口盐水入侵的影响.研究结果表明,江道地形是通过改变潮汐大小间接影响盐水入侵的,江道容积越大,潮差和进潮量越大,导致盐水入侵越严重;涌潮促使盐水入侵加剧,涌潮前后氯度存在突变.模型在钱塘江河口氯度预报中的应用结果表明,模型计算结果与实测值基本吻合,模型具有较大的预报应用价值.
Using a finite volume method based on the Godunov scheme, a two-dimensional saltwater intrusion mathematical model considering the tidal bore effect was established for forecasting chlorinity at water intakes in the Qiantang River Estuary. Based on field data and computational results from the mathematical model, the effects of main factors, including runoff, tides and tidal bore, and riverbed topography, on saltwater intrusion were analyzed. Results show that the riverbed topography affects saltwater intrusion indirectly through changing tides. The larger the river volume is, the larger the tidal range and tidal prism are, leading to intensification of saltwater intrusion. The tidal bore also enhances saltwater intrusion, as chlorinity changes abruptly before and after the tidal bore. Application of the established model in chlorinity prediction shows that the computational results of the model agree with the field data, and the model has significant application value in chlorinity prediction.