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991.
A two-dimensional finite difference numerical model, capable of predicting depth-averaged tidal flow fields in coastal and estuarine waters, has been extended to include tide-induced non-cohesive sediment transport processes. The partial differential equations governing the conservation of mass, momentum and suspended sediment in an incompressible turbulent flow are included in a depth-integrated form in the model. For the representation of the processes of erosion and deposition of sediment from the bed an empirically based source-sink term was refined, based on the results of three mobile bed flume studies. The model has been tested by simulating tidal flows and suspended sediment fluxes in two estuaries, with particular application to the Humber estuary in the U.K. The model was calibrated and found to produce an encouraging degree of agreement between the numerical predictions and corresponding field measurements for this estuary. Furthermore, the predicted gross deposition and erosion features of the estuary were found to be in close agreement with interpretations from Eulerian tidal residual predictions. 相似文献
992.
本文根据在台湾海峡西部海域同步观测的风和流的实测资料进行统计分析,得出本海域表层风海流的流速系数(流速/风速)为0.05左右,流向在风向偏右14.5°,2级以下弱风时余流流向为常流控制,3~4级时风海流控制表层和5m层余流流向,5级以上大风时,风海流能直达底层等结论。 相似文献
993.
994.
The paper documents the occurrence of long-period internal Kelvin waves in Split Channel in spring 2002. The analyses were performed on thermohaline and current data measured at three moorings and one hydrographic section. The internal oscillation had a period of 5–6 days, being larger just after the generation which was probably excited by the alongshore Sirocco wind. The recorded current amplitude was up to 0.3 m s−1 in the surface layer, while the observed pycnocline displacement was 10–15 m. The oscillation was reproduced by one-dimensional two-layered model of a channel, imposing nodal lines at its entrances. Cross-shore properties of the oscillation, such as observed offshore decrease in pycnocline amplitude, are explained by the dynamics of an internal Kelvin wave propagating along channel boundaries, because the internal Rossby radius is smaller than the width of the channel. Conclusively, the observed oscillation probably represents the fundamental mode of internal waves trapped in the channel complex off Split. 相似文献
995.
996.
根据崂山头、朝连岛、灵山岛一个月的潮位资料,采用三角形网格的分步杂交方法,建立了胶州湾及邻近海域的二维变边界潮流数值模型。并模拟了大、中、小潮三种潮汛条件下的潮流场,水位场及余流场。得出了胶州湾高潮水域面积、潮间带面积,湾口累积流通量等有关参数。 相似文献
997.
非均匀风场作用下太湖风成流风涌水的数值模拟及验证 总被引:7,自引:0,他引:7
本文采用浅水波方程数值模式,考察太湖局地风场的影响,模拟了太湖风成流,风涌水的变化情况,模拟结果与实测值符合较好,另外,将实测风场资料代入模式计算,结果表明,模拟对风涌水有较好的预报能力,流向流速的计算值与实测值在态势上较为一致。 相似文献
998.
999.
渤海中部长期流的观测与余流分析 总被引:8,自引:0,他引:8
本文用渤中8号平台长期流观测取得的资料,分析了余流的变化特征。同时,用日平均流与日平均风的互相关函数,探讨了流与风的关系。 相似文献
1000.
Harry?L.?BrydenEmail author Lisa?M.?Beal Louise?M.?Duncan 《Journal of Oceanography》2005,61(3):479-492
Using a year-long moored array of current meters and well-sampled synoptic sections, we define the variability and mean structure and transport of the Agulhas current. Nineteen current meter records indicate that time scales for the temporal variability in the alongshore and offshore velocities are 10.2 and 5.4 days, respectively. Good vertical correlation exists between the alongshore or onshore velocity fluctuations, excluding the Agulhas Undercurrent. The lateral scale for the thermocline Agulhas current is about 60 km and the onshore velocity correlations are positive throughout the Agulhas Current system. Mean velocities from the array determine that the offshore edge of the Agulhas Current lies at 203 km and the penetration depth is 2200 m offshore of the Undercurrent. Hence, daily averaged velocity sections, determined by interpolation and extrapolation of current meter locations, for a 267-day period, from the surface to 2400 m depth and from the coast out to 203 km offshore encompass the main features of the Agulhas Current system. The Agulhas current is generally found close to the continental slope, within 31 km of the coast for 211 of 267 days. There are only five days when the core of the current is found offshore at 150 km. Total transport is always poleward, varying from −121 to −9 Sv, with maximum transport occurring when the core is 62 km from the coast. Average total transport for the 267 day period is −69.7 Sv; the standard deviation in daily transport values is 21.5 Sv; and the mean transport has an estimated standard error of 4.3 Sv. The Agulhas Undercurrent, which hugs the continental slope below the zero velocity isotach, has an average equatorward transport of 4.2 Sv, standard deviation of 2.9 Sv and an estimated standard error of 0.4 Sv. Transports from the moored array are in reasonable agreement with transport results from synoptic sections. Based on time series measurements at about 30° latitude in each ocean basin, the Agulhas Current is the largest western boundary current in the world ocean. 相似文献