| 摘要: |
| 利用实际的风场和地形等条件, 基于一个浪流耦合模型提供的动力场驱动一个悬沙输送模型, 研究黄河入海泥沙在渤海中悬浮输运的季节变化特征。通过数值计算发现, 69%的黄河入海泥沙最终滞留在滨海区, 输往外海的泥沙占入海泥沙总量的31%, 尚有4%的泥沙通过渤海海峡输往北黄海。因此, 黄河口附近的悬沙含量非常高(≥1kg/m3), 且其季节变化主要受到入海水沙通量多寡的影响, 丰水丰沙的夏秋季最高。除黄河口外, 渤海其他海域海水中悬浮体含量的平面分布具有明显的地区性和季节性, 其基本趋势是悬浮体含量随离岸距离的增加而减少, 且其季节变化主要受风场时变控制。数值计算得到的悬沙输运年平均结构显示: 黄河入海泥沙部分输向渤海湾南岸; 而大部分泥沙向东南输向莱州湾, 大量泥沙并不在此沉积, 继而向东北方向输运, 莱州湾只是一个向外输沙的通道。泥沙输运通量的结构与海底冲淤之间有良好的对应关系, 最具典型代表性的是黄河口南北两侧涡状通量以及与之对应的泥质沉积区。
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| 关键词: 渤海, 数值模拟, 悬沙输运, 泥沙冲淤 |
| DOI：10.11693/hyhz200902004004 |
| 分类号: |
| 基金项目:国家自然科学基金资助项目, 40771030 号、40571020 号、40271020 号 |
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| NUMERICAL SIMULATION ON SEASONAL TRANSPORTATION OF SUSPENDED SEDIMENT FROM HUANGHE (YELLOW) RIVER TO BOHAI SEA |
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WANG Hai-Long1, LI Guo-Sheng2
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1.Guangdong Electric Power Design Institute;2.Institute of Geographic Sciences and Natural Resources Research
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| Abstract: |
| It has been recognized for years that the transportation of suspended load from the Huanghe (Yellow) River contributed greatly to shoreline position, sediment distribution, shoal erosion, and ecological environment of the Bohai Sea, the estuary host. Using data of sediment flux of the river and real forcing fields, and the bathymetry of the Bohai Sea, a numerical module driven by a wave-current coupled model was developed to simulate the seasonal cycle of suspended load transportation in the Bohai Sea. The simulation results were shown good consistency with the observation data of 2004. Physical data of 1982 were used as the initial condition for two-year numerical simulation, and the simulation result of the second year was analyzed, showing that 69% of the sediment from the river deposited on the river delta 31% conveyed to outer waters, and 4% exported to the northern Yellow Sea through the Bohai Strait. The suspended load concentration was fairly high near estuary (≥1 kg/m3). The maximum concentration occurred in summer and fall. Moreover, the spatial distribution and seasonal variation in other waters in the Bohai Sea besides the estuary were distinct. For example, the sediment concentration decreased rapidly with distance from coastal line, and stayed very low in central Bohai Sea and the offshore of Qinhuangdao (≤1×10?4 kg/m3). Except the estuary area, the seasonal variation in sediment concentration was dominated by wind fields in other Bohai Sea areas. Only a small amount of river-derived sediment was transported northwestward and reached the southern coast of the Bohai Bay, while the majority of them was transported southeastward into Laizhou Bay, moved again northeastward, and then deposited in the central Bohai Sea; and some were transported eastward alongshore to the Bohai Strait. The suspended load transportation structure simulated with the module well agreed with the deposition and erosion of the sea-bed, which is shown typically by the case that in the southern area of the estuary, the suspended load transportation rotates clockwise forming a clayey sediment zone.
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| Key words: The Bohai Sea, Numerical modeling, Suspended load Transportation, Seasonal cycle |
