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 31, Issue 4 - Nov 1994
Volume 31, Issue 3 - Aug 1994
Volume 31, Issue 2 - May 1994
Volume 31, Issue 1 - Feb 1994
Selecting the target year
Development of a Preswirl Stator Propulsion System for a 300K VLCC
Jin-Tae Lee ; Moon-Chan Kim ; Suak-Ho Van ; Ki-Sup Kim ; Ho-Chung Kim ;
Journal of the Society of Naval Architects of Korea, volume 31, issue 1, 1994, Pages 1~13
Procedures for the development of a preswirl stator-propulsion system for a VLCC 300K are described in this paper. The preswirl stator-propulsion system is one of the compound propulsor systems, which is used for the purpose of recovering propeller slipstream rotational energy by locating a stator in front of the propeller. The preswirl stator-propulsion system can be considered as a most reliable energy saving device because of its simple mechanism. Five stators are designed for the existing hull form and propeller, and their effects are verified by model tests. Open-water test result of the preswirl stator-propulsion system at the cavitation tunnel show
increase of open-water efficiency compared to that of a propeller without stators. Maximum 6.5% decrease of delivered power at the design speed(15.5knots) is expected with the designed stator based on the analysis results of resistance and self-propulsion test at the towing tank.
Calculation of Probabilistic Damage Stability Based on Grid Model
Jong-Ho Nam ; Won-Don Kim ; Kwang-Wook Kim ;
Journal of the Society of Naval Architects of Korea, volume 31, issue 1, 1994, Pages 14~21
The studios on the stability of damaged ships have been carried out continuously to prevent frequent damages or sinkings which cause large loss of life and fortunes. For dry cargo ships, continuing losses have resulted in new legislation of the probabilistic damage stability. IMO has developed requirements for the subdivison and damage stability of dry cargo ships based on probabilistic concepts. The calculation of the probabilistc damage stability is a complicated and iterative job hence development of computer programs is indispensable. In this research, programming of the probabilistic damage stability according to new requirements has been done and the results were compared with those carried out by the other foreign packages. New algorithm using a grid model in a transversal section was introduced to reduce efforts in preparing input data for damage scenarios and as a result, has brought significant improvement in efficiency and performance.
A Basic Study on the Development of Floating Fish Aggregating Devices , Part I - Laboratory Static Tests on Synthetic Fiber Ropes -
H. Shin ; K. Yamakawa ; S. Hara ; K.W. Park ;
Journal of the Society of Naval Architects of Korea, volume 31, issue 1, 1994, Pages 22~31
Fish aggregating devices(FAD) or artificial fish reefs deployed in the ocean space have been developed in various forms. The objective of FAD is to aggregate, cultivate and proliferate aquatic resources by making changes in ocean flows around it. developing spawning grounds, improving feeding areas and protecting larvae and juveniles. Most floating fish aggregating devices(FFAD) are in the form of surface buoys or subsurface buoys with a single point mooring system(SPMS). The mooring line of SPMS for the secure positions of FFAD is expected to keep great stresses as a result of the harsh ocean environment. Laboratory static tests on synthetic fiber ropes used for the SPMS were run. The Nylon wet rope specimen tests under increasing-and-decreasing loads showed about 20% strength drop. Also the logarithmic creep-tie behavior of fiber ropes was observed in the constant load test and compared with Flessner's formula.
A Study on the Model-Ship Correlation Analysis of Powering Performance
Yong-Jea Park ; Eun-Chan Kim ; Chun-Ju Lee ; Hyo-Kwan Leem ; Ho-Sun Park ;
Journal of the Society of Naval Architects of Korea, volume 31, issue 1, 1994, Pages 32~41
This paper presents the model-ship correlations based on model test results of 36 ships. All of model tests were conducted at KRISO towing tank The correlation factors
are estimated by the ITTC Standard Method and compared with the results of another towing tank. In the 36 ships, the block coefficients of thirty ships are greater than 0.72. Nevertheless the comparison of factors is in good agreement. The corrections to the scale effect on wake fraction
and roughness allowance
are subject matter in practice. The correction formulae are proposed by functions of ship length and form factor. And the correction formula of resistance coefficient
based on Townsis's hull roughness formula is presented.
A Study on the Simplified Representation of Product Model for Shipbuilding CIMS
D.Y. Yoon ; H.J. Jo ; H.W. Suh ; K.E. Kim ; Y.H. Ko ; W.J. Lee ; H.J. Kim ; H.G. Lim ; I.K. Woo ; C.B. Song ;
Journal of the Society of Naval Architects of Korea, volume 31, issue 1, 1994, Pages 42~49
The purpose of CIM for shipbuilding should be focused on the efficient processing of information among design, process planning and scheduling activities. The most essential technology for shipbuilding CIM is the product model. This model should not only define a physical product "ship" but also a process "ship production". Major activity for ship production is assembly, which requires intensive use of the relationships among parts of ship structure. Other production information are painting area. shape. weight, etc. The fact that major ship structure is "stiffened-plate" type, which allows us to handle the plate thickness as non-geometric information for practical purpose. Therefore. the geometric model for ship product model should handle the relationship among parts(so called topology) efficiently. We find that a face oriented non manifold data structure can meet this requirement. We apply this non-manifold data structure to the ship compartmentation, structural design, and assembly.
A Study on the Effectiveness of Bulbous Bow Streamline to the Ship Resistance for Large Full Form Ship
S.W. Hong ; K.J. Lee ;
Journal of the Society of Naval Architects of Korea, volume 31, issue 1, 1994, Pages 50~62
This paper presents the results of a comparative analysis of the model test results to investigate the effect of bulbous bow installed on a large full form ship to the ship resistance performance. Seven parameters related to the shape of bulbous bow were selected and varied systematically to inquire their effects experimentally. A total number of twenty-three ship models with different bulbous bow were manufactured, and resistance tests. flow visualization test, and wave profile measurement were carried out for each model. For the comparative analysis between the various bulb forms and their model test results, bulbous bow forms are classified into nine groups according to their form characteristics. From the analysis of the trend of the resistance components, it was verified that form resistance has dominant effect on the total resistance of a slow full form ship. The model test and its statistical analysis showed that the direction of streamlines around bulbous bow has close relationship with resistance components. especially with form resistance
Calculation of 3-D Navier-Stokes Equations by an IAF Method
Seung-Hyun Kwag ;
Journal of the Society of Naval Architects of Korea, volume 31, issue 1, 1994, Pages 63~70
The three-dimensional incompressible clavier-Stokes equations are solved to simulate the flow field around a Wigley model with free-surface. The IAF(Implicit Approximate Factorization) method is used to show a good success in reducing the computing time. The CPU time is almost an half of that if the IAF method were used. The present method adopts the local linearization and Euler implicit scheme without the pressure-gradient terms for the artificial viscosity. Calculations are carried out at the Reynolds number of
and the Froude numbers are 0.25, 0.289 and 0.316. For the approximations of turbulence, the Baldwin-Lomax model is used. The resulting free-surface wave configurations and the velocity vectors are compared with those by the explicit method and experiments.
Uncertainty Analysis for the Propeller Open Water Test
G.I. Choi ; H.H. Chun ; J.S. Kim ; C.M. Lee ;
Journal of the Society of Naval Architects of Korea, volume 31, issue 1, 1994, Pages 71~83
Recently, an interest in the uncertainty analysis on measurement and prediction has been growing. An uncertainty analysis method is applied to the P.O.W test where error sources, estimated errors, their propagation route and their sensitivities to the uncertainty items are clearly illustrated. The uncertainty range for the results obtained from the HMRI Propeller Open Water test is within
which is assumed to be lower than an usual measurement error range of
. It has been noticed that the uncertainty analysis can be used quite usefully for detecting dominant error-sources and hence improving the experimental measurement accuracy.
Study on Tip-Vortex Cavitation and Its Noise Characteristics - Effects of Surface Roughness -
B.S. Hyun ; C.M. Lee ; H.S. Choi ;
Journal of the Society of Naval Architects of Korea, volume 31, issue 1, 1994, Pages 84~93
The purpose of present study is to investigate the surface roughness on tip-vortex cavitation and its induced noise, emanating from an elliptic wing of NACA 0012 section. Roughness elements of
are applied to the 10% portion of wing tip, and then, the wing tip as well as the leading edge. It is shown from cavitation observation that the cavitation inception is first visible at about half chord downstream of wing tip for most experimental conditions, and developed into the tip-vortex cavitation and finally the fully developed cavitation as cavitation number is decreased. Acoustic noise generated by a tip-vortex cavitation has its frequency range of 3 kHz to 50 kHz, while the fully-developed cavitation at lower cavitation number induces a broad band spectrum. It is also shown that, when the roughness elements are applied to the wing tip and the leading edge, the cavitation characteristics and its induced noise are improved. Moreover, it is appeared that the condition at which the rough surface is at pressure side gives a better result. although its lift-drag ratio is reduced.
A Numerical Model for the Movement of Spilled Oil at Ocean
Dong-Y. Lee ; Hang-S. Choi ;
Journal of the Society of Naval Architects of Korea, volume 31, issue 1, 1994, Pages 94~101
This paper describes a short-term prediction model for the movement of an oil slick in shallow waters. Under the assumption that the initial movement of the oil slick is governed by spreading and advection, the model has been developed and applied to Kyungki-Bay near Incheon Harbor. The initial spreading is estimated by using an empirical formula. The depth-averaged momentum equations are solved numerically for the volume transport velocities, in which the
tide is the main driving source. A staggered grid system is adopted fur spatial discretization and the half-time method is implemented for time marching. The numerical result is visualized with the help of animation and thus the contaminated area is displayed on a monitor in time sequence. The input data are the time, the location and the volume of spill accident as well as environmental data such as md and
A Study on the Statistical Characteristics of Rolling Motion of Ships Using Multiple Time Scales
Yun-Cheol Na ; Sun-Hong Kwon ; Dong-Dai Ha ;
Journal of the Society of Naval Architects of Korea, volume 31, issue 1, 1994, Pages 102~110
The roll response of ships to the narrow band random exciting moment is investigated based on the multiple time scale technique. The results are compared with those calculated from statistical equivalent linearization method. The calculation results have shown that the results calculated from multiple time scale technique eve wider range of multiple values. Numerical simulations of rolling motion of ship are performed to confirm the results.
A Practical Method for Computing Wave Resistance
Seung-Joon Lee ;
Journal of the Society of Naval Architects of Korea, volume 31, issue 1, 1994, Pages 111~120
This is a continuing work of Van & Lee. Some unresolved results of theirs are first discussed more, and then Tulis's exact theory is briefly reviewed. A second order theory derived from Tulin's is used as a basis to judge the accuracy of the Poisson and the Dawson free surface boundary condition(FSBC) in the low speed region for a two-dimensional submerged body. In search of a new FSBC, a purely numerical approach is adopted, and we show one candidate and its performance, which is satisfactory to a certain degree.
On the Grounding Damage of Ship Bottom Stiffened Platings(Part I: Experiment)
Jeom-K. Paik ; Myung-H. Hyun ; Tak-K. Lee ;
Journal of the Society of Naval Architects of Korea, volume 31, issue 1, 1994, Pages 121~132
The aim of the present paper is to clarify the damage characteristics fur ship bottom stiffened platings in grounding. For this purpose, a series of tests are performed. A rigid wedge is quasi-statically pushed into the high tensile steel plates with two stiffeners. The aspect ratio of plates(a/B) is in the range from 1.0 to 2.5 and the thickness of plates is in the range from 3.4 to 7.0mm. Also other parameters, namely the shape of wedge tip, wedge angle and property/direction of stiffeners are varied. The test is carried out using the 100ton universal test machine. During the loading. both applied force and length of cutting(penetration) resulting in the grounding force-penetration response are measured.
The Development of Shipboard Noise Analysis System using Statistical Energy Analysis(I)
Hyun-J. Kang ; Hyun-S. Kim ; Jae-S. Kim ; Sung-Y. Han ; Young-C. Lee ;
Journal of the Society of Naval Architects of Korea, volume 31, issue 1, 1994, Pages 133~141
In this paper, experiences obtained during the development of MASS(Noise Analysis of Ship-board using SEA) are described. The results are summarized as follows. (1) The modelling techniques for ship structure and cabins are suggested. (2) Structureborne and airborne noise for a real ship were measured at sea trial and predicted by NASS. The differences between the two values are acceptably small for the cabins located on higher decks, although problems related with modelling of lower decks and evaluation of radiation efficiency were found.
Stochastic Imperfection Sensitivity Analyses of Stiffened Cylindrical Shells with Geometric Random Imperfection
D.K. Kim ; Y.S. Yang ;
Journal of the Society of Naval Architects of Korea, volume 31, issue 1, 1994, Pages 142~154
In this paper, stochastic imperfection sensitivity analyses of stiffened cylindrical shells under static load are presented. Multimode formulation is performed for the buckling load calculation based on the Donnell's theory and Galerkin approximation. Random imperfection field theory and response surface method are combined with deterministic bucking analysis scheme to perform stochastic imperfection sensitivity analyses of stiffened cylindrical shells considering random geometric imperfection. From the characteristics of probabilistic bucking load, the relation between reliability index and safety parameter can be obtained in addition to the relation between load and reliability index. Those results can be used to determine the range of required safety parameter and acceptable imperfection.