• International Journal of Naval Architecture and Ocean Engineering
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• v.8 no.5
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• pp.496-510
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• 2016

Simulation technology is a type of shipbuilding product lifecycle management solution used to support production planning or decision-making. Normally, most shipbuilding processes are consisted of job shop production, and the modeling and simulation require professional skills and experience on shipbuilding. For these reasons, many shipbuilding companies have difficulties adapting simulation systems, regardless of the necessity for the technology. In this paper, the data model for shipyard production simulation model generation was defined by analyzing the iterative simulation modeling procedure. The shipyard production simulation data model defined in this study contains the information necessary for the conventional simulation modeling procedure and can serve as a basis for simulation model generation. The efficacy of the developed system was validated by applying it to the simulation model generation of the panel block production line. By implementing the initial simulation model generation process, which was performed in the past with a simulation modeler, the proposed system substantially reduced the modeling time. In addition, by reducing the difficulties posed by different modeler-dependent generation methods, the proposed system makes the standardization of the simulation model quality possible.

• Korean Journal of Computational Design and Engineering
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• v.17 no.1
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• pp.17-25
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• 2012

Recently, requests for accurate process planning using simulation have been increasing in many engineering fields including the shipbuilding industry, and many application systems for simulation have been developed. It is difficult, however, for a user to reuse the developed systems, because simulation models in the system are defined by its own method. In addition, the simulation model should be modified whenever a simulation sequence, which is called simulation scenario, is changed. Therefore, in this study, an elementary simulation object is proposed to modularize a simulation model. And the management scheme of simulation scenario is proposed to manage the scenario outside of the simulation models. Also, a simulation template is proposed to increase the development efficiency. To verify the efficiency of the proposed methods, application examples for shipbuilding process planning are implemented.

• Korean Journal of Computational Design and Engineering
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• v.11 no.1
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• pp.11-19
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• 2006

For several years, a research about the simulation for shipyard and shipbuilding has been performed. This research is based on the concept of PLM (Product Lifecycle Management) and DM (Digital Manufacturing). Global leading companies and research center are trying to get a good position of PLM, especially M&S field. Digital shipbuilding is to computerize shipyard facilities and shipbuilding processes, and to simulate expected scenarios of shipbuilding processes using a computer model in order to resolve a potential problem such as a bottleneck processes, and over loaded resources. In this paper, simulation methodology for shipbuilding is described. In addition, a local and global strategy for the use of simulation methodology is suggested. Finally, case studies about an indoor shop and an outdoor shop are described.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2000.04a
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• pp.75-80
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• 2000

We revisit the arrested Ekman boundary layer problem, using a fully non-linear numerical model with the subgrid dissipation modeled by the large eddy simulation method (LES). The main objective of this study is to find out whether the dynamic balance of the arrested Ekman boundary layer explained by MacCready and Rhines (1991) is valid for high Reynolds number. The model solution indicates that for high Reynolds number and low Richardson number flows, the density anomaly diffusion by near-wall turbulent action may become intense enough to homogenize completely the density structure within the boundary layer, in the direction perpendicular to the sloping wall. Then the buoyancy effect becomes negligible allowing a near-equilibrium Ekman boundary layer flow to persist for a long period.

• International Journal of Naval Architecture and Ocean Engineering
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• v.12 no.1
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• pp.414-427
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• 2020

The finite element method is used to simulate the navigation of an ice-area bulk carrier in broken ice fields. The ice material is defined as elastic, and the simulations are accomplished at four model speeds and three ice concentrations. The movements of ice floes in the simulation are consistent with those in the model test, and the percentage deviation of the numerical ice resistance from the ice resistance in the model test can be controlled to be less than 15 %. The key characteristics of ice loads, including the average ice loads, extreme ice loads, and characteristic frequency, are analyzed thoroughly in a comprehensive manner. Moreover, the effects of sailing speed and ice concentration on the ice loads are analyzed. In particular, the stress distribution of ice floes is presented to help understand how model speed and concentration affect the ice loads. The "ice pressure" phenomenon is observed at 90 % ice concentration, and it is realistically reflected both in the time―and frequency―domain ice force curves.

• IE interfaces
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• v.15 no.3
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• pp.230-240
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• 2002

Information technologies centered on the internet in the area of shipbuilding and marine engineering further incur the needs to increase the flexibility of the organization, the dispersion of work process, and the use of out sourcing, as well as the globalization of related market. In near future, electronic commerce and concurrent engineering based on CALS/EC and the Internet will be an integral part of the environment and upon these changes, ship design and construction will become a computer supported cooperative work of many dispersed and specialized groups. As the means of active response to these environmental changes, many new concepts such as digital shipbuilding, virtual shipyard, and simulation based design are appearing. In this paper, the concept and current status of digital manufacturing in general manufacturing industry will be reviewed. Then, related technologies, area of application and methods of digital manufacturing in shipbuilding and marine industries are presented. In addition, virtual assembly simulation system for shipbuilding(VASSS), a tool for crane operability and block erection simulation in virtual dock based on 3D product model, will be introduced.

• Proceedings of the KWS Conference
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• 1998.10a
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• pp.3-8
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• 1998

This paper considers factory simulation based on shipbuilding CIM in which a computer integrated design and manufacturing system is considered. The author proposes the product model and several alterative functions for designing ship's structure, and develop a ship definition system for computer integrated design and manufacturing. This implemented system is called SODAS (System Of Design and Assembly for Shipbuilding). Object oriented concept is used to develop this system. As well as the product model, the design function cutting function, and virtual assembling function are introduced. By using the design function, any type of ship's structure can be designed. And also factory simulation can be carried out by using the cutting function and virtual assembling function.

• Special Issue of the Society of Naval Architects of Korea
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• 2011.09a
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• pp.127-132
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• 2011

In this paper, hydrodynamic performance of FSRU which is designed to operate in North America East Coast assessed. In order to estimate the dynamic performance, the numerical analysis is carried out based on a time domain simulation program to solve the coupled dynamics for floater and mooring lines which is as well known program as DNV SESAM package. The target operating area is East coast of North America and the model test was carried out based on the meta-ocean data of the area. The mooring analysis is only considered wave without other environment condition at this time. The results of the numerical analysis show the under-estimated results at the higher wave height condition. But the tendency is very similar. Also, the motion response show good agreement compared with model test.

• Proceedings of the Korea Society for Simulation Conference
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• 2003.11a
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• pp.185-192
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• 2003

Digital Manufacturing-based production could be very effective in shipbuilding in order to save costs and time, to increase safety for workers, and to prevent bottleneck processes in advance. Digital shipbuilding system, a simulation-based production tool, is being developed to achieve such aspects in Korea. To simulate material flow in a subassembly line at a shipyard, the product, process and resources was modeled for the subassembly process which consisted of several sub-processes such as tack welding, piece alignment, tack welding, and robot welding processes. The analysis and modeling were carried out by using the UML(Unified Modeling Language), an object-oriented modeling method as well as IDEF(Integration DEFinition), a functional modeling tool. Initially, the characteristics of the shop resources were analyzed using the shipyard data, and the layout of the subassembly line was designed with the resources. The production process modeling of the subassembly lines was performed using the discrete event simulation method. Using the constructed resource and process model, the productivity and efficiency of the line were investigated. The number of workers and the variations In the resource performance such as that of a new welding robot were examined to simulate the changes in productivity. The bottleneck process floated according to the performance of the new resources. The proposed model was viewed three-dimensionally in a digital environment so that interferences among objects and space allocations for the resources could be easily investigated

• Journal of Power System Engineering
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• v.16 no.4
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• pp.17-23
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• 2012

In this study, the numerical simulation and basin model test have been performed to evaluate sea worthiness and resistance performance for a small pre-planning three type of leisure boats which are U, V, Y shapes of hull forms. As a well known commercial CFD code, Maxsurf, was applied for modeling hull forms used as the solver of motion analysis. Also the model resistance test was carried out to estimate the effective power of boat in the basin tank. Numerical simulation and model test results show that Y-shaped hull is better than the other types in terms of heave and pitch motion, having a key effect on a boat sea worthiness. But V-type hull is more efficiency than others cases in resistance performance.