• Title/Summary/Keyword: 방형비척계수

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만재된 대형 광탄선박의 후진기관 사용시 발생하는 좌선회 현상 고찰

  • Son, Gi-Hak;Jeong, Tae-Gwon
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2011.06a
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    • pp.63-65
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    • 2011
  • 만재된 광탄선이 UKC가 작은 수역을 진입할 때 후진 기관을 사용하게 되면 통상의 경우와는 달리 급격한 좌선회 현상이 발생한다. 이 현상은 속력이 4노트 이상에서는 두드러지게 발생하나 3노트 미만에서는 거의 발생하고 있지 않다. 이 연구에서는 포항항에 만재된 광탄선이 선석에 접안할 때까지의 발생하는 현상을 기술하고 그 원인을 밝혀 보고자 한다. 이 원인 추후 이론적인 검토가 필요한 사항이지만 이 연구에서는 추론 가능한 사항은 선미부의 방형비척계수(CB), 작은 UKC 등을 고려한 통상적으로 작용하는 배수류의 측압작용과 좌현 선미의 선저에 배수류의 쌓임에 의한 힘으로 검토하고자 한다.

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Experimental Study on the Effects of Water Jetting on a Flapped Rudder (플랩이 부착된 타에 미치는 물 제트 분사효과에 관한 실험적인 연구)

  • Hae-Seong Ahn;Hyo-Chul Kim
    • Journal of the Society of Naval Architects of Korea
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    • v.36 no.1
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    • pp.22-29
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    • 1999
  • In the development of high speed marine vehicle, lilting devices became important in sharing the pay load or controlling the attitude. The devices are also important to meet the IMO regulation to prevent the marine pollution by keeping the high rudder force for VLCC even in low speed operation. The high lift devices such as the Coanda device have been introduced to the aircraft as a common practice for a long time among the aero-engineers. If the Coanda device can be utilized to the flapped rudder, the severe requirement of rudder force could be provided for the VLCC in low speed operation. The performance of the rudder system has been investigated at the towing tank of Seoul National University.

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Variation of the Turning Circle by the Rudder Angle and the Ship's Speed-Mainly on the Training Ship KAYA- (타각과 선속에 따른 선회권의 변화-실습선 가야호-)

  • Kim, Min-Seok;Shin, Hyeon-Ok;Kng, Kyoung-Mi;Kim, Min-Seon
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.41 no.2
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    • pp.156-164
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    • 2005
  • The size of the ship's turning circle is influenced by various factors, such as block coefficient, underwater side shape, rudder area ratio, draft, trim and Froude's number. Most of them are already fixed on departure from a port. However, the ship's speed and the rudder angle are controllable factors which operations are able to change optionally during sailing. The DGPS measured the turning circles according to the ship's speed and the rudder angle. The maximum advances by slow and full ahead were 302m and 311m, and the maximum transfers were 460m and 452m, respectively. There occurs almost no difference in size of the turning circle by variation of the ship's speeds. When the rudder angles were changed to $10^{\circ}$, $20^{\circ}$ and $30^{\circ}$, the maximum advances were 447m, 271m and 202m, and then also the maximum transfers 657m, 426m and 285m, respectively. The diameter of the tuning circle was decreased exponentially when the rudder angle was increased. The maneuverability was better when the direction of turning and propulsion of propeller are in the opposite direction rather than in the same one togetherm. The distance of the maximum transfer was always bigger than that of the maximum advance.