Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
International Journal of Ocean System Engineering
Journal Basic Information
Journal DOI :
Korean Society of Ocean Engineers
Editor in Chief :
Volume & Issues
Volume 3, Issue 4 - Nov 2013
Volume 3, Issue 3 - Aug 2013
Volume 3, Issue 2 - May 2013
Volume 3, Issue 1 - Feb 2013
Selecting the target year
Design Load Analysis of Current Power Rotor and Tower Interaction
Jo, Chul H. ; Lee, Kang-Hee ; Hwang, Su-Jin ; Lee, Jun-Ho ;
International Journal of Ocean System Engineering, volume 3, issue 4, 2013, Pages 164~168
DOI : 10.5574/IJOSE.2013.3.4.164
Tidal-current power is now recognized as a clean power resource. The turbine blade is the fundamental component of a tidal current power turbine. The kinetic energy available within a tidal current can be converted into rotational power by turbine blades. While in service, turbine blades are generally subjected to cyclic fatigue loading due to their rotation and the rotor-tower interaction. Predicting the fatigue life under a hydrodynamic fatigue load is very important to prevent blade failure while in service. To predict the fatigue life, hydrodynamic load data should be acquired. In this study, the vibration characteristics were analyzed based on three-dimensional unsteady simulations to obtain the cyclic fatigue load. Our results can be applied to the fatigue design of horizontal-axis tidal turbines.
Research on Hydrodynamic Performance of the Interaction between Ducted Propeller and Rudder based on CFD
Xie, Yonghe ; Wang, Guibiao ; Wang, Wei ;
International Journal of Ocean System Engineering, volume 3, issue 4, 2013, Pages 169~174
DOI : 10.5574/IJOSE.2013.3.4.169
The computational fluid dynamics software FLUENT is used to calculate and compare the hydrodynamic performance of the propeller-rudder system of a 42-m trawler, which is installed with a ducted propeller. The effects of rudder on the hydrodynamic performance of the ducted propeller and the wake flow behind the propeller are firstly investigated. In addition, the different rudder angles are also considered to further study the performance of this system.
Effect of Pretension on Moored Ship Response
Sajjan, Sharanabasappa C. ; Surendran, S. ;
International Journal of Ocean System Engineering, volume 3, issue 4, 2013, Pages 175~187
DOI : 10.5574/IJOSE.2012.3.4.175
Moonpools are vertical wells in a floating body used onboard many types of vessels like Exploration and drilling vessels, Production barges, Cable-laying vessels, Rock dumping vessels, Research and offshore support vessels. Moonpool gives passage to underwater activities for different types of ships as per their mission requirements. It is observed that inside a moonpool considerable relative motions may occur, depending on shape, depth of the moonpool and on the frequency range of the waves to which the ship is exposed. The vessel responses are entirely different in zero and non-zero Froude number. Former situation is paid attention in this study as the mission requirement of the platform is to be in the particular location for long period of operation. It is well known that there are two modes of responses depending on the shape of the moonpool viz., piston mode for square shape and sloshing mode for rectangular shapes with different aspect ratios of opening like 1:1.5 and 1:2 ratios. Circular shaped moonpool is also tested for measuring the responses. The vessel moored using heavy lines are modelled and tested in the wave basin. The pretensions of the lines are varied by altering the touchdown points and the dynamic tensions on the lines are measured. The different modes of oscillations of water column are measured using wave gauge and the vessel response at a particular situation is determined. RAOs calculated for various situations provide better insight to the designer.
Hydrodynamic Response of Spar with Single and Double Heave Plates in Regular Waves
Sudhakar, S. ; Nallayarasu, S. ;
International Journal of Ocean System Engineering, volume 3, issue 4, 2013, Pages 188~208
DOI : 10.5574/IJOSE.2012.3.4.188
The motion response of floating structures should be adequately low to permit the operation of rigid risers along with dry well heads. Though Spar platforms have low heave responses under lower sea state, could become unacceptable in near resonance region of wave periods. Hence the hydrodynamic response, heave in particular, must be examined to ensure that it is minimized. To reduce heave motions, external damping devices are introduced and one such effective damping device is heave plate. Addition of heave plate can provide additional viscous damping and additional added mass in the heave direction which influence the heave motion. The present study focuses on the influence of heave plate on the hydrodynamic responses of Classic Spar in regular waves. The experimental investigation has been carried out on a 1:100 scale model of Spar with single and double heave plates in regular waves. Numerical investigation has been carried out to derive the hydrodynamic responses using ANSYS AQWA. The experimental results were compared with those obtained from numerical simulation and found to be in good agreement. The influence of disk diameter ratio, wave steepness, pretension in the mooring line and relative spacing between the plates on the hydrodynamic responses of Spar are evaluated and presented.
Study on Mooring System Design of Floating Offshore Wind Turbine in Jeju Offshore Area
Kim, Hyungjun ; Jeon, Gi-Young ; Choung, Joonmo ; Yoon, Sung-Won ;
International Journal of Ocean System Engineering, volume 3, issue 4, 2013, Pages 209~217
DOI : 10.5574/IJOSE.2012.3.4.209
This paper presents a mooring design procedure for a floating offshore wind turbine. Offshore environmental data for Jeju are taken from KHOA (Korea Hydrographic and Oceanographic Administration) and used for the environmental conditions in numerical analyses. A semi-submersible-type floating wind system with a 5-MW-class wind turbine studied by the DeepCwind Consortium is applied. Catenary mooring with a studless chain is chosen as the mooring system. Design deliverables such as the nominal sizes of chain and length of the mooring line are decided by considering the long-term prediction of the breaking strength of the mooring lines where a 100-year return period is used. The designed mooring system is verified using a fatigue calculation based on rain-flow cycle counting, an S-N curve, and a Miner's damage summation of rule. The mooring tension process is obtained from time-domain motion analyses using ANSYS/AQWA.
Development of Hovering AUV Test-bed for Underwater Explorations and Operations
Byun, Seung-Woo ; Choi, Hyeung-Sik ; Kim, Joon-Young ;
International Journal of Ocean System Engineering, volume 3, issue 4, 2013, Pages 218~224
DOI : 10.5574/IJOSE.2012.3.4.218
This paper describes the design and control of a hovering AUV test-bed and analyzes the dynamic performance of the vehicle using simulation programs. The main purpose of this vehicle is to carry out fundamental tests of its station keeping, attitude control, and desired position tracking. Its configuration is similar to the general appearance of an ROV for underwater operations, and its dimensions are
. It has four 450-W thrusters for longitudinal/lateral/vertical propulsion and is equipped with a pressure sensor for measuring the water depth and a magnetic compass for measuring its heading angle. The navigation of the vehicle is controlled by an onboard Pentium III-class computer, which runs with the help of the Windows XP operating system. This provides an appropriate environment for developing the various algorithms needed for developing and advancing a hovering AUV.
Comparison of Sloshing Pressures in 2D and 3D Tanks
Kim, Yonghwan ; Kim, Sang-Yeob ; Kim, Jieung ; Lee, Jae-Hoon ;
International Journal of Ocean System Engineering, volume 3, issue 4, 2013, Pages 225~230
DOI : 10.5574/IJOSE.2012.3.4.225
This paper introduces the experimental results of sloshing model tests carried out at Seoul National University. Two 1/50-scale tanks, i.e., 2D and 3D models with the same shape, were manufactured for the comparative study. Particular interest was taken in the differences in impact pressures between the 2D and 3D models. Regular motion tests were conducted for different filling depths. For each filling depth, 500 cycles of regular excitation were imposed at each frequency. To observe the characteristics and severity of sloshing from the acquired pressure data, statistical analyses were performed, not only for the peak pressure, but also for the area-concept indices, which represented the amount of impulse.