경량 등부표의 파랑 중 운동성능 추정에 관한 수치적 연구

Abstract

By its shape and colors, the light-buoy shows the route to vessels sailing nearby in the daytime, while by its lighting at night. It also plays a role in notifying the presence of obstacles such as reefs and shallows. When the light-buoy operates in the ocean, the visibility and angle of light from the lantern installed on the light-buoys change. The change of those may cause them to function improperly. Therefore, it needs for the light-buoy to have stable and minimum motions under given environmental conditions, mainly waves. In this study, motion analysis for a newly-developed lightweight light-buoy in waves were performed to predict the motion performance and to check the effect of the developed appendages on the performance. Firstly, free decay tests including benchmark cases by CFD were carried out to estimate the viscous damping coefficients, which cannot be obtained by potential-based simulations. The results from potential-based simulations with considering viscous damping coefficients, which are estimated by CFD, were compared. Also, motion simulations in regular waves using CFD were carried out to compare with the potential-based simulation. It was confirmed that the pitch and heave motions of the light-buoy became smaller by adopting the developed appendages.