本文使用以流量驅動之二維水深平均淺水模式 (Shallow-Water Model, SWM)，模式驗證係於渠道中放置一障礙物衍生渦街特性，與理論分析呈現合理之一致性。本模式應用於黑潮流場與綠島尾流之模擬。前人研究多以流速驅動SWM來模擬海洋水動力，謝 (2014) 與周 (2015) 曾以流速驅動之SWM模擬季風和颱風對於黑潮流場與綠島尾流之影響，其計算結果之水位值過大不符實際現象，使用流量驅動在控制方程式中能遵守質量守恆，但其缺點在於若流量太大時計算不穩定，且模式相對於使用流速驅動較難收斂求解。本文先以渠道中的障礙物為例計算不同的雷諾數與史特豪數之關係是否合乎經驗公式 (Williamson and Brown, 1998)，使用網格為最小平方有限元素法搭配八點四邊形網格。接著以流速驅動之SWM使用相同條件計算同樣案例並互相比對，經與理論校驗後證明以流量驅動所計算之渦街是合理的。
接著本模式應用於黑潮衍生綠島尾流之簡單情況模擬，使用平底床模擬，故數值模擬結果與流速驅動之結果比較發現差異不大，待模式發展完善後人模擬真實底床應能展現兩者差異。

A shallow-water model (SWM) based on shallow water equations (SWEs) using surface elevation and fluxes (η, qx, qy) as variables (Wang and Connor, 1975) was developed. Theoretical formulation is performed on the basis of the depth-averaged SWEs. Least-squares method with eight-node quadrilateral finite-element for space interpolations and theta-method for time integration are used to develop the SWM. SWM was applied to the case of flow past a flat channel. Numerical results are fairly compared with results obtained by the SWM using surface elevation and depth-averaged velocities (η, u, v) as variables. Numerical results of SWM based on (η, qx, qy) apparently show better accuracy and flux conservation than those based on the variable (η, u, v) of SWM.

The SWM is then utilized to study Green Island wakes induced by the Kuroshio. Characteristics of the downstream vortex, such as the aspect ratio and period, are examined and compared with results of obtained by the variable (η, u, v) of SWM in previous study. However we still need to fix the open boundary condition, the water depth is limited only in 10 m and velocity lower than 0.5 m/s, comparing to previous study setting that water depth is 360 m and velocity is 1.0 m/s. Finally we discuss the vortex street in the case of water depth 10 m and flux 5 m2/s.

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