• 대한조선학회논문집
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• 제49권4호
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• pp.327-332
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• 2012

International Towing Tank Conference (ITTC) recommended verifying a ship's ability to move transversely at zero forward speed without altering heading by a crabbing test. In sea trial, all available propellers/rudders/thrusters should be used to find the maximum possible transverse speed. For estimating crabbing ability in the design stage, tests to estimate possible swaying force and yawing moment range using all available propellers/rudders/thrusters are conducted. By butterfly diagram, which compares possible swaying force and yawing moment range with external swaying force and yawing moment by wind, a ship's crabbing ability can be estimated. In this study, model tests of a cruise vessel equipped with bow thrusters and POD system were conducted to find out her crabbing ability in the design stage. To mimic quay condition, a model quay-wall was set in the towing tank.

• 한국해양공학회지
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• 제28권1호
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• pp.1-5
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• 2014

Chosun University, in cooperation with SPP shipyard, has developed an energy saving device based on a new concept: "Crown Duct." Crown Duct is composed of a semi-duct with short struts inside and outside the duct. Theoretical calculations for two different designs were carried out using the CFD code "Ship Flow." The design selected from these two different forms by the CFD code analysis was tested in a towing tank at SSPA. The results showed about 4% efficiency gain under a full-load condition and about 7% gain under a ballast condition in the towing tank test.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2008년도 춘계학술발표회
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• pp.43-47
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• 2008

예부선 운항 시 부두의 전안, 이안 및 좁은 수로를 항행할 경우 접할 수 있는 안벽근처의 항행과, 두 선박이 접근하여 평행항의 상을 반대 방향으로 항과 할 경우의 유체력 상호작용을 살펴보기 위하여, 본 연구에서는 예선의 부선 예항 시뮬레이션을 실시한 후 부선의 선수방향, 예선의 회두 모멘트와 횡방향의 힘과 같은 유체력 특성을 조사 및 분석하여 그에 따르는 안전한 예부선의 조선방안을 제시하였다.

• Journal of Ship and Ocean Technology
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• 제9권2호
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• pp.29-36
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• 2005

A hull form of Baltic ice class IA Aframax tanker has been developed taking into consideration of powering performance in brash ice channels based on IA class rules. Speed performance of the ship hull form in normal seagoing has been validated through model tests in a towing tank. The hull form design developed in this work has demonstrated good speed performance in normal seagoing although the ship design is entitled to ice class IA.

• 대한조선학회지
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• 제3권1호
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• pp.3-10
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• 1966

• 수산해양기술연구
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• 제29권4호
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• pp.260-271
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• 1993

Due to depletion of fish resources as time goes on, the trawl fishing industries which have caught the demersal fish is confronting with financial difficulties. For the purpose of breaking these difficulties, trawlers are expanding the fishing targets to the midwater from bottom stock. The trawlers become to be able to detect the fish schools not only vertical but also horizontal direction by equipping the sonar system on board. Even though the operator locates the fish school by sonar, it is not easy to make a desirable catch of the fish school which is detected, for the reason of the maneuverring characteristics of trawler. For the purpose of enhancing the efficiency of a fish catch, the auther performed a series of on board experiments to investigate the maneuverablilites of midwater trawaler. The obtained results are summerized as follows: 1. The higher the RPM of main engine, the smaller the magnitude of turning circle. And it is smaller in the right than in the left turning 2. Towing speed varies irregularly under turning novenment. When the RPM of main engine being 560, 680 the angular velocities are 11.3deg/min, 22.5deg/min respectively. 3. The difference of new course distance between calculated by maneuverring indices and measured by experimental ship is high when altering course being large and towing speed low. 4. The faster the towing speed is, the shorter the new course distance becomes. When towing speed is same in right and left turning movement, the now course distance is shorter in case of right turning movement than in left. 5. It is considered to be convenient for a navigator to utilize the curves for altering course in order to steer the ship rapidly and accurately.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2005년도 추계학술대회지
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• pp.47-52
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• 2005

최근 예부선 결합선박에 대한 해양사고가 빈발하고 있다. 어선을 제외한 선박사고 중 $36\%$로 가장 높은 비율을 차지하고 있으며, 매년 예부선에 의한 해양사고가 증가하고 있다. 예부선에 의한 해양사고는 증가하고 있으나 예부선의 안전 운항 방안에 대한 체계적인 연구가 없는 실정이다. 본 연구는 예부선에 대하여 인적요소부분, 안전시설 부분, 운항요소부분으로 분류하여 문제점을 도출하고 그에 대한 개선방안을 제시하여 예부선에 의한 해양사고를 방지하는데 목적이 있다.

• 대한조선학회논문집
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• 제55권2호
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• pp.169-177
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• 2018

Twisted rudder, twisted rudder with bulb, and twisted rudder with bulb and fin have been developed computationally for 3,000 TEU container ship through parametric study. The objective function is to minimize delivered power in model scale. Design variables are twisted angle, rudder bulb diameter and fin angle. The governing equation is Reynolds averaged Navier-Stokes equations in an unsteady turbulent flow and the Reynolds stress model applied for the turbulent closure. A double body model is used for the treatment of free-surface. The calculation was carried out in towing and self-propulsion conditions at design speed. The sliding mesh technique was employed to simulate the flow around the propeller. Form factor is obtained from the towing computation. Self-propulsion point is obtained from the self-propelled computations at two propeller rotating speeds. The delivered power due to the designed twisted rudder, twisted rudder with bulb, and twisted rudder with bulb and fin are reduced by 1.1%, 1.6%, and 2.0%, respectively.

• 대한조선학회논문집
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• 제31권1호
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• pp.32-41
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• 1994

선박해양공학연구센터 예인수조에서 시험되었던 선박 가운데 선형과 프로펠러가 모형과 실선이 동일하였던 36척에 대하여 모형선-실선상관해석을 수행하였다. 뚱뚱한 선형이 대부분임에도 불구하고, 타수조의 결과보다 약간 나은 일치를 보였다. 통계적 처리에 의하여 반류비 수정계수와 거칠기 수정계수에 대한 회귀식을 구하였고, Townsin의 거칠기계수를 적용한 경우의 저항수정계수에 대한 식을 도출하였다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2015년도 추계학술대회
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• pp.37-39
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• 2015

The ships transiting the Northern Sea Route (NSR) have been gradually increased so that the number of ship-ice collision accidents would be increased. The collision between ship and ice floe can lead to serious damage of hulls and decline of ship's maneuverability. In this study, collision tests that a model ship is forced to collide with disk-shaped synthetic ice floes are conducted in a towing tank. The synthetic ice floes made of polypropylene which has similar density with real ice are used. The ice load is measured by a load cell installed on the carriage rod. The ice floe's motion is measured by a motion sensor installed on the synthetic ice floe. The influences of contact conditions such as hull form and ship speed on the ship-ice collision response are investigated and discussed by measured peak force and ice floe's motion.