병렬 계류된 부유체에 작용하는 파랑표류력의 시간영역 해석

Abstract

Wave-induced motions and forces of side-by-side moored vessels are numerically investigated with focus on wave mean drift forces. In this paper, Side-by-side moored FPSO and shuttle tanker studied by Hong et al.(2002) are revisited using two numerical methods. For frequency-domain analysis, higher-order boundary element method (HOBEM) using wave Green function is utilized. About selected cases, direct time-domain simulations using finite element method are carried out. Comparison is made on both 6 degree-of-freedom vessel motions and second-order mean drift forces. Two different gap distances in head sea condition are studied and the effect of gap distance on sway mean drift forces is observed. Major discrepancies between experiments and numerical computations are happened in the range of resonant frequencies of trapped water. To remedy this discrepancies, effective gap distance is considered.