The research of the floating

Tomoyuki Horikomi,Kuniaki Shoji,Kiyokazu Minami 한국항해항만학회 2006 한국항해항만학회 학술대회논문집 Vol.2006 No.-

A floating-type wave power pump is a device which sends air into water by using wave power. The floating-type wave power pump has the new configuration composed of a curved surface reflection board, a slope, and phase plates. As a result of a water-tank experiment, it turned out that the floating-type wave power pump with a curved surface reflection board and a slope raised power and efficiency in the wide wavelength waves. The result of a marine experiment was also preferable. The floating-type wave power pump sends air into the sea by using wave power, so it can be used for the improvement of marine environment. In addition, the floating body constituted of a curved surface reflection board, a slope, and phase plates, is effective as a device to utilize the energy of a wave. Therefore, it can be widely used for a wave power generation, pumping up deep seawater.

Monitoring system for the wind-induced dynamic motion of 1/100-scale spar-type floating offshore wind turbine

C.M. Kim,조진래,S.R. Kim,이연승 한국풍공학회 2017 Wind and Structures, An International Journal (WAS Vol.24 No.4

Differing from the fixed-type, the dynamic motion of floating-type offshore wind turbines is very sensitive to wind and wave excitations. Thus, the sensing and monitoring of its motion is important to evaluate the dynamic responses to the external excitation. In this context, a monitoring system for sensing and processing the wind-induced dynamic motion of spar-type floating offshore wind turbine is developed in this study. It is developed by integrating a 1/00 scale model of 2.5MW spar-type floating offshore wind turbine, water basin equipped with the wind generator, sensing and data acquisition systems, real-time CompactRIO controller and monitoring program. The scale model with the upper rotatable blades is installed within the basin by means of three mooring lines, and its translational and rotational motions are detected by 3-axis inclinometer and accelerometers and gyroscope. The detected motion signals are processed using a real-time controller CompactRIO to calculate the acceleration and tilting angle of nacelle and the attitude of floating platform. The developed monitoring system is demonstrated and validated by measuring and evaluating the time histories and trajectories of nacelle and platform motions for three different wind velocities and for eight different fairlead positions.

Monitoring system for the wind-induced dynamic motion of 1/100-scale spar-type floating offshore wind turbine

Kim, C.M.,Cho, J.R.,Kim, S.R.,Lee, Y.S. Techno-Press 2017 Wind and Structures, An International Journal (WAS Vol.24 No.4

Differing from the fixed-type, the dynamic motion of floating-type offshore wind turbines is very sensitive to wind and wave excitations. Thus, the sensing and monitoring of its motion is important to evaluate the dynamic responses to the external excitation. In this context, a monitoring system for sensing and processing the wind-induced dynamic motion of spar-type floating offshore wind turbine is developed in this study. It is developed by integrating a 1/00 scale model of 2.5MW spar-type floating offshore wind turbine, water basin equipped with the wind generator, sensing and data acquisition systems, real-time CompactRIO controller and monitoring program. The scale model with the upper rotatable blades is installed within the basin by means of three mooring lines, and its translational and rotational motions are detected by 3-axis inclinometer and accelerometers and gyroscope. The detected motion signals are processed using a real-time controller CompactRIO to calculate the acceleration and tilting angle of nacelle and the attitude of floating platform. The developed monitoring system is demonstrated and validated by measuring and evaluating the time histories and trajectories of nacelle and platform motions for three different wind velocities and for eight different fairlead positions.

계류장치 연결 위치가 Spar Type 부유식 해상풍력 발전기의 동적 응답에 미치는 영향 해석

조양욱(Cho, Yanguk),조진래(Cho, Jinrae),정의봉(Jeong, Weuibong) 한국소음진동공학회 2013 한국소음진동공학회 논문집 Vol.23 No.5

This paper deals with the analysis of dynamic characteristics of mooring system of floating-type offshore wind turbine. A spar-type floating structure which consists of a nacelle, a tower and the platform excepting blades, is used to model the floating wind turbine and connect three catenary cables to substructure. The motion of floating structure is simulated when the mooring system is attached using irregular wave Pierson-Moskowitz model. The mooring system is analyzed by changing cable position of floating structure. The dynamic behavior characteristics of mooring system are investigated comparing with cable tension and 6-dof motion of floating structure. These characteristics are much useful to initial design of floating-type structure. From the simulation results, the optimized design parameter that is cable position of connect point of mooring cable can be obtained.

부유식 재생에너지 플랜트의 개념설계를 통한 계류라인의 피로설계

정준모(Joonmo Choung),이민성(Min-Sung Lee),전상익(Sang-Ik Jeon) 대한조선학회 2011 대한조선학회 학술대회자료집 Vol.2011 No.6

This paper presents the concept design precedure of floating-type combined renewable energy platform based on hydrodynamic analyses and the fatigue design procedure of taut-type mooring lines. Two types of combined renewable energy platforms are taken into account: first combination of wind, wave, and photovoltanic energies and second combination of wind , current, photovoltanic energies. The concept design is from the literature survey, but main dimensions have been decided based on the basic hydrostatic calculation. Fully coupled hydrodynamic analyses have been carried out to identify motion characteristics of the floating body and tension histories of each mooring lines. Further fatigue lives using rainflow cycle counting method, API stress-life diagram, and Palmgren-Miner rule are predicted for chain link-type taut mooring system. Finally mooring lines satisfying design life of twenty years are proposed.

Fatigue Design of Mooring Lines of Floating Type Combined Renewable Energy Platforms

Choung, Joon-Mo,Jeon, Sang-Ik,Lee, Min-Seong Korean Society of Ocean Engineers 2011 International journal of ocean system engineering Vol.1 No.3

This paper presents the concept design procedure of a floating-type combined renewable energy platform based on hydrodynamic analyses and is focused on the fatigue design of taut-type mooring lines of the platform. Two types of combined renewable energy platforms are considered: a combination of wind turbine, wave turbine and photovoltaic energy plant and a combination of wind turbine, current turbine and photovoltaic energy plant. The basic configurations are conceptually determined from the understanding of floating offshore plants, while the main dimensions have been determined based on a hydrostatic calculation. Fully coupled hydrodynamic analyses have been carried out to identify the motion characteristics of the floating body and the tension histories of the mooring lines. The tension history is used for the fatigue life prediction based on the rain-flow cycle counting method. For the fatigue life prediction, tension life curves from API and the Palmgren-Miner rule are employed.

Surrogate Model Based Approximate Optimization of Passive Type Deck Support Frame for Offshore Plant Float-over Installation

Dong Jun Lee,Chang Yong Song,Kangsu Lee 한국해양공학회 2021 韓國海洋工學會誌 Vol.35 No.2

The paper deals with comparative study of various surrogate models based approximate optimization in the structural design of the passive type deck support frame under design load conditions. The passive type deck support frame was devised to facilitate both transportation and installation of 20,000 ton class topside. Structural analysis was performed using the finite element method to evaluate the strength performance of the passive type deck support frame in its initial design stage. In the structural analysis, the strength performances were evaluated for various design load conditions. The optimum design problem based on surrogate model was formulated such that thickness sizing variables of main structure members were determined by minimizing the weight of the passive type deck support frame subject to the strength performance constraints. The surrogate models used in the approximate optimization were response surface method, Kriging model, and Chebyshev orthogonal polynomials. In the context of numerical performances, the solution results from approximate optimization were compared to actual non-approximate optimization. The response surface method among the surrogate models used in the approximate optimization showed the most appropriate optimum design results for the structure design of the passive type deck support frame.

메타모델을 이용한 플로트오버 설치 작업용 능동형 갑판지지프레임의 근사설계최적화

이동준,송창용,이강수,Lee, Dong Jun,Song, Chang Yong,Lee, Kangsu 한국산업융합학회 2021 한국산업융합학회 논문집 Vol.24 No.1

In this study, approximate design optimization using various meta-models was performed for the structural design of active type deck support frame. The active type deck support frame was newly developed to facilitate both transportation and installation of 20,000 ton class offshore plant topside. Structural analysis was carried out using the finite element method to evaluate the strength performance of the active type deck support frame in its initial design stage. In the structural analysis, the strength performances were evaluated for various design load conditions that were regulated in ship classification organization. The approximate optimum design problem based on meta-model was formulated such that thickness sizing variables of main structure members were determined by achieving the minimum weight of the active type deck support frame subject to the strength performance constraints. The meta-models used in the approximate design optimization were response surface method, Kriging model, and Chebyshev orthogonal polynomials. The results from approximate design optimization were compared to actual non-approximate design optimization. The Chebyshev orthogonal polynomials among the meta-models used in the approximate design optimization represented the most pertinent optimum design results for the structure design of the active type deck support frame.

Numerical prediction for the performance of a floating-type breakwater by using a two-dimensional particle method

Lee, Byung-Hyuk,Hwang, Sung-Chul,Nam, Jung-Woo,Park, Jong-Chun Korean Society of Ocean Engineers 2011 International journal of ocean system engineering Vol.1 No.1

The nonlinear free-surface motions interacting with a floating body were investigated using the Moving Particle Semi-implicit (MPS) method proposed by Koshizuka and Oka [6] for incompressible flow. In the numerical method, more realistic Lagrangian moving particles were used for solving the flow field instead of the Eulerian approach with a grid system. Therefore, the convection terms and time derivatives in the Navier-Stokes equation can be calculated more directly, without any numerical diffusion, instabilities, or topological failure. The MPS method was applied to a numerical simulation of predicting the efficiency of floating-type breakwater interacting with waves.

추적식 수상 태양광발전 시스템의 설계 및 시공

김선희 ( Sun Hee Kim ),이영근 ( Young Guen Lee ),서수홍 ( Su Hong Seo ),주형중 ( Hyung Joong Joo ),윤순종 ( Soon Jong Yoon ) 한국복합재료학회 2014 Composites research Vol.27 No.2

대부분의 에너지는 전세계적으로 제한되어 있는 석유, 석탄, 천연가스 등 주로 화석연료로부터 얻어지고 있다. 최근, 고유가, 석유자원의 고갈, 기후변화 등이 신재생에너지를 포함한 비화석 연료가 세계적으로 주목을 받고 있는 이유 중의 하나이다. 이 연구에서는 고비강성 및 비강도, 고내부식성 및 내화학성 등을 장점으로 갖고 있는 펄트루젼 FRP(PFRP)를 사용하였다. 따라서 부유식 구조물의 설계와 시공을 위해서는 PFRP 재료가 우선적으로 선택될 수 있다. 추적식 수상 태양광발전 구조물의 설계는 유한요소해석 결과를 사용하여 수행되었으며, 구조물은 조립되어 수상에 설치되었다. 구조물을 설치하기 전에 안전성 문제를 유한요소법을 사용하여 검토하였으며, 그 결과 설계, 제작, 시공된 구조물은 외적으로 작용된 하중을 지지하는데 충분히 안전함을 알 수 있었다. Most of energy are obtained from oil, coal, and natural gas, most likely, fossil fuel which is limited throughout the world. Recently, high crude oil price, climate change, oil depletion, etc. are main reason to get attention to non-fossil energy including renewable energy in the world. In this study, we studied analysis and design of structure system composed of pultruded fiber reinforced polymer composite (PFRP) which has many advantages such as high specific strength and stiffness, high corrosion resistance and chemical resistance. For the design and construction of floating-type structure, PFRP structural members may be the first choice. Design of tracking-type floating PV generation structure was performed by using the results of the finite element analysis. The structure is fabricated and installed on the water surface. Before the installation of the structure, safety related problems associated with installation and operation are investigated using the finite element simulation and it was found that the structure is safe enough to resist externally applied loads.