ハングオフライザーの挙動特性に関する研究

概要

論文の詳細を見る
Results of model experiments and numerical simulations concerning the dynamic behaviours of riser system in hung-off (disconected mode) are presented. To design marine riser system and to decide the most suitable material and size of the riser pipe, estimation of nonlinear behaviours in hung-off mode is essential to check the riser strength especially in case of deep water riser system. In this paper, behaviours of hung-off riser in 400〜500 m water depth are studied by model experiments and numerical simulations and the results are discussed to show the dynamic properties of the system. In model experiments using 4 m long elastic riser model, (1/100 scale), deflections and bending moment are measured at some points along the model and axial force was also measured at the top. In numerical simulation, the riser system is expressed as assembly of many beam elements. Dynamic bending and twisting behaviours are expressed using Lagrange function. Bending and twisting behaviours are numerically simulated by solving these equations using Newmark-β method. As the results of the studies, the numerical simulation presented is shown to be sufficient to predict the hung-off riser behaviours mainly consists of bending and twisting oscilations.
社団法人日本船舶海洋工学会の論文