• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2005년도 추계학술대회 논문집
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• pp.319-325
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• 2005

본 연구의 목적은 초대형 컨테이너선 기항에 따른 컨테이너터미널의 항만생산성을 예측하는 것이다. 일반적으로 컨테이너터미널의 생산성은 컨테이너크레인, 야드크레인, 야드트랙터 등을 포함한 하역시스템의 생산성에 의해 평가된다. 그러므로 부산항 컨테이너터미널의 항만 생산성으로서 컨테이너크레인의 현재 생산성을 분석하고 초대형 컨테이너선에 의한 컨테이너를 처리하기 위한 순작업 생산성과 총작업 생산성을 예측한다. 생산성 향상을 위해 하역시스템 대안과 운영시스템 대안을 요약한다.

• 한국해양공학회지
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• 제34권2호
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• pp.120-127
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• 2020

Evaluation of fatigue strength considering the springing effect of very large container ships is crucial in the design stage. In this study, we established a fatigue strength evaluation method considering a linear springing component in the frequency domain. Based on a three-dimensional global model, a fluid-structure interaction analysis was performed and the modal superposition method was applied to determine the hot spot stress at the hatch corner of very large container ships. Fatigue damage was directly estimated using the stress transfer function with a linear springing response. Furthermore, we proposed a new methodology to apply the springing effect to fatigue damage using hull girder loads. Subsequently, we estimated the fatigue damage contribution due to linear springing components along the ship length. Finally, we discussed the practical application of the proposed methods.

• 대한조선학회논문집
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• 제43권1호
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• pp.15-21
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• 2006

Recently, the attention to large container ships whose size is greater than 10,000 TEU container ship has been increased due to their increasing demand. The large container ship has twin skegs because of the engine capacity and large beam-draft ratio. In this paper, the maneuvering characteristics of a container ship with twin skegs were investigated through 4DOF(four degree of freedom) HPMM(Horizontal Planar Motion Mechanism) test and computer simulation. A mathematical model for maneuvering motion with 4DOF of twin skegs system was established to include effects of roll motion on the maneuvering motion. And to obtain roll-coupling hydrodynamic coefficients of a container ship, 4DOF HPMM system of MOERI which has a roll moment measurement system was used. HPMM tests were carried out for a 12,000 TEU class container ship with twin skegs at scantling load condition. Using the hydrodynamic coefficients obtained, simulations were made to predict the maneuvering motion. Rudder forces of twin-rudders were measured at the angles of drift and rudder. The neutral rudder angles with drift angles of ship was quite different with those of single skeg ship. So other treatment of flow straightening coefficient $\gamma_R$ was used and the simulation results was compared with general simulation result. The treatment of experimental result at static drift and rudder test was very important to predict the maneuverability of a container ship with twin skegs.

• International Journal of Ocean System Engineering
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• 제2권3호
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• pp.170-175
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• 2012

Currently, most logistics use containers. The construction of new port and high speed medium size container ship for the transportation of merchandise have become very important. The problem of ship stability is also important because of its direct influence on the loss of human life, ships, and merchandise. The stability of a container ship during its operation is not a large problem because it is well considered in the design process. However, the assessment of ship stability during container loading/unloading in port still depends on the expertise of experienced personnel. In this paper, a model based simulation system is introduced, which is able to assess ship stability during container loading/unloading, using ENVISION, a general purpose simulation system.

• 해양환경안전학회지
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• 제27권3호
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• pp.409-420
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• 2021

The decrease in under keel clearance (UKC) due to the increase of draft that occurs during advancing and turning of very large vessels of different types was analyzed based on computational fluid dynamics (CFD). The trim change in the Duisburg test case (DTC) container ship was much smaller than that of the KRISO very large crude oil carrier 2 (KVLCC2). The sinkage of both ships increased gradually as the water depth became shallower. The amount of sinkage change in DTC was greater than that in KVLCC2. The maximum heel angle was much larger for DTC than for KVLCC2. Both ships showed outward heel angles up to medium-deep water. However, when the water depth became shallow, an inward heel was generated by the shallow water effect. The inward heel increased rapidly in very shallow water. For DTC, the reduction ratio was very large at very shallow water. DTC appeared to be larger than KVLCC2 in terms of the decreased UKC because of shallow water in advancing and turning. In this study, a new result was derived showing that a ship turning in a steady state due to the influence of shallow water can incline inward, which is the turning direction.

• 대한조선학회논문집
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• 제48권1호
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• pp.84-92
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• 2011

This paper presents the primary conceptual design results of Smart Harbor. As the world trade becomes active, so container cargo volume is increasing constantly. Since the coming of very large container ships, It's necessary that a harbor handles many containers more than before. Therefore, we designed the new concept of SMART HARBOR which overcomes land site problem for port expansion and geographic constraints of very large container ships in harbor.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2005년도 춘계학술대회 논문집
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• pp.325-332
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• 2005

최근 들어 초대형 선박에 대한 논의가 활발해진 가운데 선사들은 선박 대형화로 인한 규모의 경제 효과를 꾸준히 추구하고 있다. 기술과 경제성이 보장되는 한 당분간 이러한 선박 대형화의 추세는 지속될 전망이다. 선박대형화에 따라 거주공간의 위치변화에 대한 필요성이 조심스럽게 제기되고 있다. 본 논문은 초대형 컨테이너선의 거주 공간 재배치에 따른 경제성 평가 분석에 관한 내용을 다루었다. 선박의 초기 설계 단계에서, 도면 생성의 보완과 검증을 통하여 거주구역과 엔진실의 공간을 분리하는 제안을 하였다. 그에 관한 장단점을 분석하고, 실현 가능성 여부를 경제성 평가 분석을 통해 검토하였다. 경제성 평가 방법을 위한 목적함수는 요구운임지수를 사용하였다. TEU 증가에 의한 경제성을 전망하고, 이러한 공간 재배치에 따른 조선소와 선주의 경제성 평가를 분석하여, 선적 개수의 증가에 따른 경제성 전망을 제시하였다.

• 한국항해학회지
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• 제14권4호
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• pp.1-15
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• 1990

With increasing ship's speed turnround and port time becomes a large percentage of total roundtrip time and this causes to accelerate the introduction of the various kind of modern handling equipment, the standardization of cargoes, and the improvement of the ship. However, it is still a drag on efficient operation of ship. Similarly, the turnround time at the container port is very important as a measure for the decision of the efficiency of port. To decrease operating coasts, the minimization of the time need to cargo handling at the ports of call must be achieved. Thus the optimization of the time need to cargo handling at the ports of call must be achieved. Thus the optimized Container Loading Plan is necessary, especially under the rapid speed of container operations. For the container loading plan, in this thesis, we use the hungarian method and the branch and bound method to get the initial disposition of both maximization of ship's GM and minimization of shift number to the obstructive container in a yard area. We apply the dynamic programming algorithm to get the final disposition for minimizing total turnroudn time and finally we analyzed the results to check whether the initial disposition is proper or not.

• International Journal of Naval Architecture and Ocean Engineering
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• 제12권1호
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• pp.387-398
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• 2020

In the design stage of the very large container ships, some methodologies for the whipping effects have been developed, but most of them are based on single sea state. We developed a methodology that considers multiple sea states. Fluid-structure Interaction (FSI) analyses with one dimensional structural model were carried out to capture slamming-induced transient whipping behaviors. Because of the nature of random phases of the applied wave spectra, the required period for entire FSI analyses was determined from the convergence study where the whipping effect became stable. Low pass filtering was applied to the transient whipping responses to obtain the hull girder bending moment processes. Peak counting method for the filtered whipping responses was used to obtain collection of the vertical bending moment peaks. The whipping effect from this new method is compared with that from based on single sea state approach. The efficiency and advantage of the new methodology are presented.

• 대한조선학회논문집
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• 제41권1호
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• pp.15-22
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• 2004

Twin-skeg type stern shapes are recently adopted for very large commercial ships. However it is difficult to apply a CFD system to a hull form having twin-skeg, since grid topology around a twin-skeg type stern is more complicated than that of a conventional single-screw ship, or of an open-shaft type twin-screw ship with center-skeg. In the present study a surface mesh generator and a multi-block field grid generation program have been developed for twin-skeg type stern. Furthermore, multi-block flow solvers are utilized for potential and viscous flow analysis around a twin-skeg type stern The present computational system is applied to a 15,000TEU container ship with twin-skeg to prove the applicability. Wave profiles and wake distribution are calculated using the developed flow analysis tools and the results are compared with towing tank measurements.