A Study of Current Characteristics at the Entrance of Keelung Harbor
2010
Hochschulschrift
Zugriff:
98
The purpose of this study is aimed to investigate the characteristics of current field near the entrance of Keelung Harbor. The survey approaches are based on the Lagrangian Method and Eulerien Method, respectively. The DGPS drifter buoys were employed to measure the surface current field in the interested area. Besides, the traction device, namely ADCP, was used to record the current data on the waterway. The characteristics of current in different tidal conditions were realized by analyzing the measure data in summer and autumn, respectively. For the data obtained by ADCP, the findings show that dominate current directions in both summer and autumn are between E to NE and SE to SW. In addition, the current velocities in the vertical direction are all less than 90 cm/s and the quantities become decreased as the water depth increasing. For the measurement data of drifter buoys, the findings represent that current directions near water surface are between E to NE and WNW to WSW in summer and autumn, respectively. The maximum surface velocity never exceeds 1.2m/s. Finally, the maximum surface velocity in the waterway is 87 cm/s and the regime of current directions are irregular. For further analysis of current field changes near port of Keelung concerning the east breakwater extension, numerical simulation has been preceded by MIKE-21 HD model. A verified calculation was performed in advance to determine the more suitable and accurate parameters as HD model input by compared with the data from field observations. From the results of this study, it demonstrated that the current velocity at the flood was faster than that at the ebb, and the maximum velocity was less than 1.0 m/s. The current direction at the flood was in southwest, and in northeast at the ebb. The current direction at harbor entrance was the same at the flood and the ebb, and a counterclockwise circulation was formed due to the topographic effect. This phenomenon can be found from the results of HD model numerical simulation.
Titel: |
A Study of Current Characteristics at the Entrance of Keelung Harbor
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Autor/in / Beteiligte Person: | Lo, Cheng-Yao ; 羅政耀 |
Link: | |
Veröffentlichung: | 2010 |
Medientyp: | Hochschulschrift |
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