• Title/Summary/Keyword: marine investigation

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CFD prediction and simulation of a pumpjet propulsor

  • Lu, Lin;Pan, Guang;Sahoo, Prasanta K.
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.8 no.1
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    • pp.110-116
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    • 2016
  • In this study an attempt has been made to study the hydrodynamic performance of pumpjet propulsor. Numerical investigation based on the Reynolds Averaged NaviereStokes (RANS) computational fluid dynamics (CFD) method has been carried out. The structured grid and SST ${\kappa}-{\omega}$ turbulence model have been applied. The numerical simulations of open water performance of marine propeller E779A are carried out with different advance ratios to verify the numerical simulation method. Results show that the thrust and the torque are in good agreements with experimental data. The grid independent inspection is applied to verify accuracy of numerical simulation grid. The numerical predictions of hydrodynamic performance of pumpjet propulsor are carried out with different advance ratios. Results indicate that the rotor provides the main thrust of propulsor and the balance performance of propulsor is generally satisfactory. Additionally, the curve of propulsor efficiency is in good agreement with experimental data. Furthermore, the pressure distributions around rotor and stator blades are reasonable. Beyond that, the existence of tip clearance accounts for the appearance of tip vortex that leads to a further loss in efficiency and a probability of cavitation phenomenon.

An Analysis of Human Factor in Marine Accidents - Collision Accidents - (해양사고의 인적요인 분석에 관한 연구 - 선박충돌사고를 중심으로 -)

  • Yang Won-Jae;Kwon Suk-jae;Keum Jong-Soo
    • Proceedings of KOSOMES biannual meeting
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    • 2004.05b
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    • pp.7-11
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    • 2004
  • Maritime safety and marine environmental protection are the most important topic in marine society. But, so many marine accidents rave been occurred with the development of marine transportation industry. On the other side, ship is being operated under a highly dynamic environment and many factors are related with ship's collision Nowadays, the increasing tendency to the human errors of ship's collision is remarkable, and the investigation of the human errors has been heavily concentrated. This study analysed on the human errors of ship's collision related to the negligence of lookout and classified basic error type using GEMS(Generic Error Modeling System) dynamic model.

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A Study on the Standard Criteria of Solid Particle Separation Test for Marine Centrifugal Purifier (선박용 정유기 고형분 분리 성능시험 규격기준에 관한 연구)

  • Jeong, Sang-Hu
    • Journal of Advanced Marine Engineering and Technology
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    • v.31 no.8
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    • pp.1028-1034
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    • 2007
  • In order to establish a criteria of solid particle separation performance test on marine centrifugal purifier at factory acceptance test, an investigation had been done on criteria of test standards, regulations and test specifications of purifier manufactures. KS V 7836, fuel oil and lubricating oil purifiers for marine use-centrifugal type, the criteria of solid particle separation is studied in the point of reality, restricts and analysis method. It is proposed that a reasonable criteria and analysis method should be adopted, and the current criteria shall be revised to adequate levels considering reasonable basis and industrial technology levels. Also, the test analysis conceptions, separation efficiency method and particle size restriction method, are reviewed to fulfil separation performance test for marine centrifugal purifiers.

Practical investigation of a monopod fabrication method and the numerical investigation of its up-righting process

  • Hafez, Khaled A.;Ismael, Maged M.
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.5 no.3
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    • pp.431-453
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    • 2013
  • The principal purpose of this paper is to present a novel two phases rational scenario applied in constructing an offshore monopod platform; in which the two phases are the all-ground horizontal construction phase and the post-construction phase. Concerning the all-ground construction phase, a brief investigation of its different stages, i.e., pre-fabrication, fabrication, pre-assembling, positioning, assembling, and surface finishing is introduced. The important practical aspects of such construction phase are investigated without going into the nitty-gritty of the details involved therein. Concerning the post-construction phase, a clear investigation of its sequential stages, i.e., lifting, moving and up-righting is introduced. A finite element model (FEM) of the monopod platform is created to perform the structural analysis necessary to decide the suspension points/devices and the handling scenario during the various stages of the post-construction phase on a rational wise. Such structural analysis is performed within the framework of the three dimensional quasi-static modeling and analysis aiming at simulating the realistic handling condition, and hence introducing a reliable physical interpretation of the numerical results. For the whole effort to be demonstrated efficiently, the results obtained are analyzed, the conclusions are presented, and few related recommendations are suggested.

The Marine Safety Judgment Management System for Scientific Investigation and Analysis of Marine Accidents (해양사고의 과학적인 수사 및 분석을 위한 해양안전심판관리 시스템)

  • Kim, Jeong-Rok;Jong, Jae-Yong;Im, Nam-Kyun;Kim, Chol-Seong
    • Proceedings of KOSOMES biannual meeting
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    • 2006.11a
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    • pp.9-13
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    • 2006
  • In the marine accidents judgment, investigation of truth of matters is one of important process to find out the reason of ship collision accidents. In this paper, reproduce system of ship collision accidents using ship manoeuvirng simulator technique will be introduced with which marine accidents can be easily reproduced in visual display at the case of marine accidents trial. In this system if the users select the type of ship and location of accidents, the process of ship collision will be provided in 2D and 3D display. The system also provides environmental visualizationdisplay such as fog whether and day-night view including various view angle that can be helpful to find out the reason of accidents.

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A Study on the Measure for Prevention of Marine Pollution due to the Coastal Activities (해안활동으로 인한 해양오염방지 방안 마련 연구)

  • Gug, Seung-Gi;Seol, Dong-Il;Lee, Seung-Huan;Piao, Yong-Nan
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.29 no.1
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    • pp.319-324
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    • 2005
  • This study was carried out for the purpose of proposing the guideline for the non-mischief and comfortable coastal leisure activities to reduce the marine pollution caused by sea fishing and strengthen the marine management and supervision for the fishing activity. In research method, a extensive reference was examined and analyzed, and the questionnaire investigation and field work were carried out to recognize the present conditions and problems concerning the environmental pollution caused by sea fishing. At the same time, the guideline for the safe and comfortable activities was proposed by diagnosing of actual evil conditions of marine environment due to the sea fishing activity and by analyzing of foreign mangement cases. On the basis of these research results, it is useful to contrive a management criteria for the realities investigation on the pollution of coastal activities. It also contributes to develop the regional economy by controlling coastal leisure activities effectively and systematically through the national publicity for the prevention of marine pollution.

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