해양수서생물이 해상풍력 발전시스템의 기초구조에 미치는 영향 및 억제방안에 관한 연구

Abstract

In general offshore industry, different foundation types (monopile, jacket, tripod,floating) can be used for offshore wind turbine to support this structure in different sea conditions. Recently, the most wind turbines using monopile or gravity as a foundations, but it can work under less water depths. To overcome that problems, nowadays choosing a jacket type foundation as a good choice for the intermediate water depth in 20~50 m. The marine growth formation is one of the major obstacle in off-shore industry because of reducing the life time and efficiency. Further more investigation is required to solve this issue. In this view, this work aimed to investigate the effect of marine growth on jacket foundation in off-shore wind turbine. For calculating hydrodynamic load, a jacket foundation was designed using GH Bladed ver 4.2. The effect of marine growth thickness on the natural frequency of off-shore wind turbine was investigated using Eigen mode. The results showed that the natural frequency of off-shore wind turbine reduced due to increasing the marine growth thickness. Further, also the marine growth effect on different section of jacket foundation was analyzed . Compared to TP leg and X-brace (M.S.L), the mud leg showed higher amount marine growth formation. Based on that results, the bending moment and shear force of jacket foundation at mud leg was analyzed. It is concluded that marine growth highly affect the bending moment (side to side mode) and the axial force. Finally, ZnO nanopaint was developed using ball milling for the prevention of marine growth. The growth of marine organism on bare and ZnO nanopaint coatings are examined. The experimental results confirmed that ZnO nanopaint coatings prevented the grwoth of marin organism. This work showed that the ZnO nanopaint can be used as a marine growth inhibitor for off-shore wind turbine applications.