厦门西港潮汐潮流的数值计算

NUMERICAL CALCULATION OF TIDES AND TIDAL CURRENTS IN THE XIAMEN XIGANG HARBOUR

厦门西港是一个内海港,其海水运动的主要形式是潮流。根据实测资料分析所知,厦门西港是正规半日潮性质的海区。本文着重讨论厦门西港半日分潮的数值模拟结果,其可用于研究污染物在半日分潮流作用下的稀释扩散规律和泥沙回淤规律等,并且可以了解港区潮汐潮流的概况,对于海港工程也有一定的参考价值。一、运动方程和连续方程采用直角坐标系,XOY平面与平均海面重合,X、Y轴分别与地理坐标E、N交角为35度,Z轴向上,Y轴与水边界平行。

Tides and tidal currents in the Xiamen Xigang Harbour were computed based on alternating direction implicit method in time step of 60 seconds and space step of 400 meters.Computative results prove that tidal currents are reversing and maximum flood and ebb tides occur mostly on the narrow channel of the harbour.Difference of time of high water from the bay mouth to top is 10-20 minutes.Ebb current is bigger than the flood one in the main part of the harbour,due to the runoff influences of the Jiulong Jiang River.Tidal waves,one the whole stationary,transport into the harbour from the bay mouth,the closer the waves to the top,the bigger the tidal range and the smaller the tidal currents.Flood current occurs 3-3.5 hours before high tide.Slack tide occurs half an hour before and after high and low tides.The maximum residual current in the harbour pressents at the river mouth of the Jiulong Jiang River.It should be mentioned that a clock-wise residual current exists around the Baozhuyu Island and this is different from reports of other authors.