Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal of the Society of Naval Architects of Korea
Journal Basic Information
Journal DOI :
The Society of Naval Architects of Korea
Editor in Chief :
Volume & Issues
Volume 46, Issue 6 - Dec 2009
Volume 46, Issue 5 - Oct 2009
Volume 46, Issue 4 - Aug 2009
Volume 46, Issue 3 - Jun 2009
Volume 46, Issue 2 - Apr 2009
Volume 46, Issue 1 - Feb 2009
Selecting the target year
The Comparison of Flow Simulation Results around a KLNG Model Ship
Kim, Byoung-Nam ; Kim, Wu-Joan ; Kim, Kwang-Soo ; Park, Il-Ryong ;
Journal of the Society of Naval Architects of Korea, volume 46, issue 3, 2009, Pages 219~231
DOI : 10.3744/SNAK.2009.46.3.219
Numerical simulations have been carried out for a 138K LNG Carrier (KLNG) model ship with free surface, using WAVIS 2.0 and Fluent 6.3.26 with various
values and different grid densities. Level-set method for free surface capturing was adopted in WAVIS, while VOF has been used in Fluent. The calculated results were compared with the experiment data. Resistance coefficient, wave pattern, wave profile along the hull surface, axial velocity contours and transverse vectors had been analyzed. When the first
value was fixed at 60, the simulation results from both WAVIS and Fluent were improved as the number of grids increased. The convergence time of WAVIS was much shorter than that of Fluent. Furthermore, WAVIS predicted the velocity field and the wave profile along the hull surface better than Fluent. However, Fluent gave better wave patterns.
A Study on the Numerical Methodologies of Hydroelasticity Analysis for Ship Springing Problem
Kim, Yoo-Il ; Kim, Kyong-Hwan ; Kim, Yong-Hwan ;
Journal of the Society of Naval Architects of Korea, volume 46, issue 3, 2009, Pages 232~248
DOI : 10.3744/SNAK.2009.46.3.232
Numerical methodology to solve ship springing problem, which is basically fluid-structure interaction problem, was explored in this study. Solution of this hydroelasticity problem was sought by coupling higher order B-spline Rankine panel method and finite element method in time domain, each of which is introduced for fluid and structure domain respectively. Even though varieties of different combinations in terms of numerical scheme are possible and have been tried by many researchers to solve the problem, no systematic study regarding the characteristics of each scheme has been done so far. Here, extensive case studies have been done on the numerical schemes especially focusing on the iteration method, FE analysis of beam-like structure, handling of forward speed problem and so on. Two different iteration scheme, Newton style one and fixed point iteration, were tried in this study and results were compared between the two. For the solution of the FE-based equation of motion, direct integration and modal superposition method were compared with each other from the viewpoint of its efficiency and accuracy. Finally, calculation of second derivative of basis potential, which is difficult to obtain with accuracy within grid-based method like BEM was discussed.
Use of Discrete Vortex Method for VIV Response Analysis
Kim, Yoo-Chul ; Rheem, Chang-Kyu ;
Journal of the Society of Naval Architects of Korea, volume 46, issue 3, 2009, Pages 249~258
DOI : 10.3744/SNAK.2009.46.3.249
DVM (Discrete Vortex Method) is a numerical scheme that handles discrete vortex particles to express continuous vorticity field. This scheme is proper to VIV (Vortex Induced Vibration) analysis because there is no need to generate field grids and VIV is caused by separated vorticity from the body. When DVM is applied to VIV analysis, there are some applicable schemes such as using vortex blobs, integral method for computing induced velocity, etc. In this study, the influences of these schemes are investigated and the practical scheme that is appropriate for VIV analysis is proposed.
Prediction of Ship Maneuverability by Circular Motion Test
Shin, Hyun-Kyoung ; Jung, Jae-Hwan ; Lee, Ho-Young ;
Journal of the Society of Naval Architects of Korea, volume 46, issue 3, 2009, Pages 259~267
DOI : 10.3744/SNAK.2009.46.3.259
Recently, ship maneuverability has been very important issue due to accidents of frequent occurrence at sea. IMO standards for ship maneuverability were applied from January 1, 2004. In this study, maneuverability model tests were considered through a 2m-class KVLCC1 in the Ocean Engineering Wide Tank at University of Ulsan(UOU). Circular Motion Test(CMT) was performed to obtain the maneuvering coefficients by using X-Y Carriage. The trajectories simulated using the coefficients are compared with those of PMM test and free running test.
A Numerical Study for Improvement of the Speed-performance of a Ship with Flow Control Flat Plate
Park, Dong-Woo ; Choi, Hee-Jong ; Yoon, Hyun-Sik ; Chun, Ho-Hwan ;
Journal of the Society of Naval Architects of Korea, volume 46, issue 3, 2009, Pages 268~278
DOI : 10.3744/SNAK.2009.46.3.268
The present study focused on evaluation for the performance of the Flow Control Flat Plate (FCFP) attached in the stern side of the ship. The important function of this FCFP is to enhance the resistance performance through the decrease of stern sinkage and the propulsive performance by the adjustment of inflow velocities in the propeller plane. Two different hull forms were considered to identify the effects of the FCFP. The attachment position, the angle and the size of the FCFP were studied in this numerical simulation. In this paper, the roles of the FCFP were intended to analyze fully through the numerical interpretation.
Development of the Weight Reduction Program for Corrugated Bulkheads of a Product Oil Carrier
Shin, Sang-Hoon ; Ko, Dae-Eun ;
Journal of the Society of Naval Architects of Korea, volume 46, issue 3, 2009, Pages 279~289
DOI : 10.3744/SNAK.2009.46.3.279
For a Product Oil Carrier, longitudinal bulkhead as well as transverse one is corrugated shape in general and intersection part of bulkheads is utilized for a pipe trunk. Since lower and upper stools are to be connected with all of longitudinal and transverse bulkheads, they have a uniform height respectively. The purpose of this study is the development of design system for the minimization of total weight of longitudinal and transverse bulkheads at the initial design stage. In this study, the beam element models for longitudinal and transverse corrugated bulkheads are established and they are applied to the structural analysis. For the practical design, the selection and the position of an additional pipe trunk are considered in this study. In addition the required minimum distance between the bracket installed along the web of corrugation at lower stool and the diaphragm is taken into consideration during optimization process. Evolution strategy(ES) is adopted as an optimization technique.
Parametric Study of the Vibration Transmissibility for the Rubber Mount of the Seawater-Conveying Pipe in a Ship
Han, Hyung-Suk ; Jeong, Weui-Bong ;
Journal of the Society of Naval Architects of Korea, volume 46, issue 3, 2009, Pages 290~302
DOI : 10.3744/SNAK.2009.46.3.290
Pipe system widely used in a ship is usually attached to the hull of a ship, and its vibration lead to structure-borne noise. Rubber mount is usually used as a vibration isolator of a pipe in a ship. In this paper, the effects of several factors, besides the stiffness and damping of the rubber mount, on vibration-isolating performance are taken into consideration. The parameters considered in this paper are hardness of the rubber material, painting on the rubber and deformation from clamping. Through the results of parametric study, the effective specifications of rubber mount are suggested to improve vibration-isolating performance. The performance under fluid flowing condition is calculated numerically and verified experimentally.
Block Erection Simulation Using the Integrated System of Combined Discrete Event and Discrete Time Simulation Kernel
Cha, Ju-Hwan ; Roh, Myung-Il ; Cho, Doo-Yeoun ; Lee, Kyu-Yeul ;
Journal of the Society of Naval Architects of Korea, volume 46, issue 3, 2009, Pages 303~312
DOI : 10.3744/SNAK.2009.46.3.303
Recently, requests for the accurate process planning using modeling and simulation technique are increasing in many engineering fields including shipbuilding industry. In this study, Combined DEVS(Discrete EVent System specification) and DTSS(Discrete Time System Specification) simulation kernel is developed, and an integration strategy of dynamics simulation module and graphics module is also implemented. To evaluate the efficiency and applicability of the simulation kernel and integration strategy, these are applied to the block erection simulation of offshore structures.
A Study on Deception Ship for Ship Susceptibility Improvement based on System Engineering Approach
Kang, Hee-Jin ; Shin, Jong-Gye ; Lee, Dong-Kon ; Choi, Jin ;
Journal of the Society of Naval Architects of Korea, volume 46, issue 3, 2009, Pages 313~314
DOI : 10.3744/SNAK.2009.46.3.313
To project military power, the paradigm of the modern warship aquisition has evolved with more large platform and high-technology equipment. For example, the Aegis combat system equipped warship is one of the most advanced and capable defense systems currently in use. Concurrently, if the warship attacked and disabled, it may worse the asymmetry of the battle field and it also depress the morale of the fleet. For that reason, to keep and protect few number of the big and high technology equipped warship from enemy is very important. At the present, the performance of unit weapon has enhanced remarkably. A Korean-built SS-209 class submarine, Lee Chun-ham, participated in Naval Exercise Tandem Thrust conducted in 1999, sink the target ship ex-USS Oklahoma by a single torpedo. USS Stark was struck on May 17, 1987, by two Exocet anti ship missiles and disabled. For this reason, susceptibility should be prior to vulnerability and recoverability. In this paper, deception ship which is small and chief but has very similar signatures to large and high technology equiped warship has conceptually studied by using systems engineering approach. And it may be a effective way to enhance the susceptibility of the key fighting power.
Process Improvements for Elevating Pre-outfitting Rate of FPSO
Shin, Sung-Chul ; Cho, Jong-Burm ; Shin, Ki-Young ; Kim, Soo-Young ;
Journal of the Society of Naval Architects of Korea, volume 46, issue 3, 2009, Pages 325~334
DOI : 10.3744/SNAK.2009.46.3.325
Generally, functional design of FPSO has been done by the engineering firm designated by ship owner. Main equipment such as topside facility is imported from abroad. But sometimes, OFE (Owner Furnished Equipment) does not satisfy the PND (Product Need Date) of each production stage because the delivery date of OFE is not scheduled to satisfy the PND. And sometimes many loose items and equipment are complex from engineering which does not consider pre-outfitting. Main objective of this study is process improvements by maximizing pre-outfitting rate in the stage of equipping STP (Submerged Turret Production), one of main equipment on FPSO. In this study, we analyzed the factors which obstructed pre-equipping STP using the past records of FPSO projects.
A Study on the Effects of Weight and Center of Gravity of a Planing Craft on Running Attitude
Kim, Dong-Jin ; Rhee, Key-Pyo ; Park, Han-Sol ;
Journal of the Society of Naval Architects of Korea, volume 46, issue 3, 2009, Pages 335~342
DOI : 10.3744/SNAK.2009.46.3.335
Motion characteristics of a planing craft are sensitively changed according to its weight and longitudinal center of gravity. In this paper, planing craft model tests were performed in calm water for various test conditions and Froude numbers. Sinkage and trim were measured to analyze the relations between the attitudes of a planing craft and the weight and center of gravity of it. Theoretical formula for the prediction of the attitudes of a prismatic planing hull was modified so that it can be applied to the prediction of the attitudes of a non-prismatic planing hull, and the calculation results by the modified formula were in good agreements with the experimental data.
A Study on the Damage Safety Assessment in Ship Design Stage
Lee, Dong-Kon ; Choi, Jin ; Park, Beom-Jin ; Kang, Hee-Jin ; Lim, Seok-Nam ;
Journal of the Society of Naval Architects of Korea, volume 46, issue 3, 2009, Pages 343~350
DOI : 10.3744/SNAK.2009.46.3.343
Recently ship safety regulations are being reinforced to improve maritime safety and to prevent maritime pollution by International Maritime Organization. It means that the regulation is becoming more proactive rather than reactive. In the mean time, design philosophy is also moving from rule based design to performance and simulation based design. In this paper, a study on practical application of the damage safety assessment system is carried out. The damage stability and the survivability of a cargo ship that was designed based on current regulation is investigated using performance based design tools in order to improve the safety of the design and verify the performance of the developed damage safety assessment system. To do this, damage scenarios is established and the characteristics and geometry the cargo ship is modeled. A new design alternative is proposed with small change in the internal arrangement based on safety evaluation results of the current design.
Construction Cost Estimation on the Initial Design Stage of Naval Ships based on a Product Configuration Model
Oh, Dae-Kyun ; Jeong, Yeon-Hwan ; Shin, Jong-Gye ; Choi, Yang-Ryul ;
Journal of the Society of Naval Architects of Korea, volume 46, issue 3, 2009, Pages 351~361
DOI : 10.3744/SNAK.2009.46.3.351
Many manufacturers define the system of a new product flexibility, and take advantage of previous-product information using the product configuration concept. Product configuration is an approach that defines the system of a new product centered on the product structure by referring to the previous-product information. In this paper, it is established how to apply the concept of a product configuration utilizing previous-ships information in construction cost estimation process systematically and effectively. For this, we define the advanced-construction cost estimation process based on a naval ship product model, and design construction cost estimating model. It is validated that this process and model have the applicability through the case study of the construction cost estimating of the mine-warfare ship.
Decision Supporting Methodology and System Based on Theory of Constraints for Optimal Product Portfolio Strategy in Shipbuilding Industry
Kim, In-Il ; Han, Seong-Hwan ; Kwon, Min-Chull ;
Journal of the Society of Naval Architects of Korea, volume 46, issue 3, 2009, Pages 362~371
DOI : 10.3744/SNAK.2009.46.3.362
Shipbuilding is a typical 'build to order' industry. It has a business model that generates revenues from building various ships and offshore products in accordance with owner's requirements at each production stage. Under uncertainty in shipping market, it is very essential for the shipbuilder to prepare the fast and competitive decision for product portfolio strategy in order to maximize contribution margin by exploiting production facilities and constraints. In this study, we introduce the unique decision supporting methodology for the optimal product portfolio sets based on Theory of Constraints(TOC). This methodology is established by adopting the concept of Drum Buffer Rope(DBR) in constraints planning and Throughput Accounting (TA) in management accounting of TOC. In addition, Decision Supporting System(DSS) is implemented. This DSS system provides a throughput estimator with reflecting the cost structure of shipbuilding industry and a resource simulator built on heuristic algorithms to operate major constraint-resources in shipyard such as dock, quay and pre-erection area etc. Several examples are presented to show that the proposed methodology and system can effectively support the strategic decision-making process of a global shipbuilding company.