貨櫃船機艙段遭受碰撞之抗撞能力探討

Crashworthiness of Struck Engine Room Section of Container Ship in Collision

船舶機艙配置船舶動力系統、電力系統、重要儀電系統，為船舶動力與操控核心部位，如遭撞擊將造成船舶重大損失，且燃油外洩的機率很高。本文探討8,000 TEU貨櫃船機艙段遭受同級貨櫃船側向撞擊過程的結構損壞與衝擊狀況，共考慮7種不同設計狀況，分析船舶碰撞發生後，撞擊船之船艏與被撞船之機艙段產生的破壞狀況。分別從撞擊船艏與被撞船側進行改變設計，以檢討抗撞能力之提升。船艏方面考慮一般船艏與高可變形船艏對撞擊損壞之影響；高可變形船艏係指船艙前端勁度明顯降低，但改用高延性鋼材。被撞船側考慮雙層殼內採用增加水平肋板、增加橫向大肋骨圈、採用高延性材料等以提高船側結構之勁度或延性；另外考量雙層殼艙間局部充水，水面沖激效應之吸能與沖激力效應。本文以LS-DYNA非線性有限元素程式進行船舶碰撞分析，分析結果顯示使用高可變形船艏對撞擊過程之抗撞能力提升效果最顯著；雙層殼艙間局部充水中沖激效應可吸收部分能量，佔整體損壞吸能比例雖不高，但水面沖激力影響可略提高抗撞能力，其效果並不比局部結構加強差，且船體結構不必修改，只需作微小的艙間局部充水之安排。 The engine room holds the power resource and the system control center of the whole ship. Damages of this part caused by collision may induce the most serious loss of all collision conditions. In this paper, the damage of structures for a bulbous bow of an 8000 TEU container ship striking the engine room section of the similar size of container ship was investigated. Seven different designs were considered to compare the crashworthiness between different design in ship collision. The modification of local structures in double hull, using of high deformable bow, high ductile steel for double structure, and effects of partial filled fluid in double hull were investigated. The results show that introduction of high deformable bow can improve the crashworthiness remarkably. The modification of local structures in double hull has only small benefit and can be neglected. The adoption of high ductile steel can apparently decrease the damage depth caused by collision, but may have wider damage area. Partial filled fluid in double hull will induce sloshing impact in tank wall after impact. The effect of sloshing impact in double hull in ship collision can improve a little the energy dissipation of striking bow and also reduce the acceleration at C.G. of main engine.