| 摘要: |
| 强潮河口盐水入侵对饮用水源地危害极大。基于平面二维水动力盐度模型, 对典型强潮河口—钱塘江的水动力及盐水入侵过程进行了数值模拟研究。结果表明枯水径流时盐度变化与潮位过程曲线类似, 潮差对盐度大小影响显著, 径流量的增加将逐渐减小其相似程度。当流量增加到一定程度后, 继续增加的一定径流量所产生的抑咸效果减弱, 水资源有效利用率降低, 此时允许水源地盐度超标并改从蓄淡避咸水库取水可有效节约水资源。盐度平面分布显示, 盐水入侵在强潮河口弯道处受涨潮流主流线影响明显, 靠近主流线一岸的盐度大于对岸, 单从盐水入侵角度考虑, 强潮河口弯道段的取水口应设置在远离涨潮流主流线一岸。钱塘江河口盐度数值模拟对于研究减轻盐水入侵对水源地危害的措施具有指导意义。 |
| 关键词: 盐度 数值模拟 |
| DOI：10.11693/hyhz201305002002 |
| 分类号: |
| 基金项目:国家自然科学基金项目, 50839001号, 50979036号。 |
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| Numerical sIMULATION of Summer Circulation in Taihu Lake |
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ZHOU Jie-Yuan1, SHEN Yong-Ming2, WANG Jin-Hua3
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1.Hunan Provincial Communications Planning, Survey and Design Institute;2.State Key Laboratory of Coastal and Offshore Engineering, Dalian University Of Technology;3.Nanjing Hydraulic Research Institute
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| Abstract: |
| We simulated the circulation of Taihu Lake based on an ocean model in unstructured grid and finite-volume with three-dimensional primitive equation. The model could fit well the irregular coastal boundary and numerous small islands with the unstructured triangular grid. By analyzing wind, river runoff, baroclinic pressure, the Coriolis Force, and topography, the formation and characteristics of the lake circulation during summer were modeled systematically. Results show that the horizontal circulation was mainly wind-driven; the vertical velocity was about 10?6 m/s, much smaller than the horizontal one. Weak vertical circulation could be found in some places. Throughput flow could not lead to horizontal circulation. Affected by the shallow depth, the density current was unstable, and so the horizontal circulation was seldom formed. The topographical effect caused downwind circulation in shallow water while upwind in deep water. In addition, the circulation could be formed if wind force was strong enough even in the condition of flat bottom topography. |
| Key words: Taihu Lake circulation finite-volume method unstructured grid |
