碩士 / 國立臺灣海洋大學 / 系統工程暨造船學系 / 107 / In order to investigate the wake at self-propulsion conditions in waves, KCS ship model is used in this thesis to simulate the self-propulsion in the regular waves. For the ship motion and added resistance, the computational results of RANS are in good agreement with the experimental data. Two different approaches which were named as “fixed method” and “motion method” are applied to self-propulsion simulations in waves. For the fixed method, the self-propulsion is only simulated in calm water, and the added resistance is computed separately by RANS method. For the motion method, the computation is made by simulating the ship with a propeller with given rotational speed in waves. To compare the wake difference between “fixed method” and “motion method”, we calculate the induced velocities in waves according to the linear wave theory, and add them into the wake velocities of “fixed method”. We named it as “modified fixed method”. Then we compared the wake difference between “modified fixed method” and “motion method” and use these wake velocities as the propeller inflow. The performance of the propeller is analyzed to understand the feasibility of theoretical method. From the wake analysis, it can be seen that the mean velocity of “modified fixed method” is lower than that of motion method, and the tangential and radial velocity variations calculated by two approaches have good agreements. From the force analysis, it can be seen that the differences of tangential and radial velocity have little effects on the thrust coefficient of the propeller. However, the axial velocity does have impact on the propeller thrust. The method developed in this thesis tries to establish an efficient method to simulate complicated real sea keeping problems, the computations of axial velocity still has room for improve, and more research is necessary.
| Identifer | oai:union.ndltd.org:TW/107NTOU5345020 |
| Date | January 2019 |
| Creators | Zhou, Chen-Shan, 周辰珊 |
| Contributors | Hsin, Ching-Yeh, 辛敬業 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 91 |
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