碩士 / 國立成功大學 / 造船及船舶機械工程學系 / 89 / This paper investigates the directional stability of a ship running at high speeds equal to the wave celerity in severe following and quartering seas(encounter frequency equates zero). Because of the actions of wave force and moment, the directional stability of a ship in following waves is quite different from that in calm water. A linearized sway-roll-yaw model is used to find the eigenvalues which can determine the ship directional stability. Based on the numerical solutions of a nonlinear six degrees of freedom mathematical model, simulation analysis is also conducted for the motions of the ship unsteered and steered. The former is to verify the reliability of the analytic results of the ship directional stability, and the later is to examine the effect of the automatic control system on the stability. From the results of analyses, it is realized the autopilot has significant effect on the course stability of a ship surfing in following seas; but the control system may become invalid, and a broaching might occur when the ship is surfing in quartering seas.
| Identifer | oai:union.ndltd.org:TW/089NCKU0345034 |
| Date | January 2001 |
| Creators | LO CHIH-HONG, 羅志宏 |
| Contributors | LEE MING-LING, 李銘霖 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 0 |
Page generated in 0.002 seconds