해상풍력구조물 운송 및 설치 중 파랑응답 비교

Abstract

This paper compares the wave-induced responses of an offshore wind turbine in towing and installation. Encounter wave frequency is higher and the period is shorter in towing condition with ship speed than in installation without speed. So, hydro-dynamic behavior is different although the sea state is the same. A 10 MW offshore wind turbine with a supporting tower and three legs was analyzed to compare wave-induced responses in towing and installation. Floating body motions and section forces at the tower and leg bases were calculated by solving dynamic coupled equations in the time domain. Wave forces were calculated by superposition of force RAO and wave spectrum. The encounter wave spectrum was applied in the case of towing. The pitch motion of the floating body and bending moments and shear forces at tower and leg bases were larger in the case of installation, while axial forces at the tower and leg bases were larger in the case of towing because heave acceleration was larger.