风暴潮和天文潮条件下的底摩擦的研究

THE STUDY OF OCEAN BOTTOM FRICTION:APPLYING TO STORM SURGES AND ASTRONOMICAL TIDES

由海底摩擦与平均流速的平方成正比的公式,对底摩擦的性质(主要对拖曳系数C_0)进行讨论。研究在风暴潮和天文潮的条件下,海底摩擦与风速,风向和海深等因素的关系,得到有关奇异区的存在等结论,说明在整个海区内拖曳系数不为常数。

The sea bottom stress is conventionally assumed to be directly proportional to the square of vertically averaged velocity,i.e.We also think that the drag coefficient is dep-dendent on typhoon wind field and the direction of its movement,the depth of the sea,the dimension of the sea region and the tidal period and so on.In this paper a three-dimensional numerical model is used to discuss the relation between the drag coefficient and the above-mentioned factors.From the calculation it can be obtained that the relation is valid,that drag coefficient is a constant in most part of thesea concerned ( which is called the Regular Area),and that there is a small area near the coastline where the drag coefficient is far greater than other area (which is called the Singular Area)We have also obtained a series of conclusions about the relation between drag coefficient and typhoon wind field and the direction of its movement,the sea depth and so on.