波激颤振对破冰型LNG船结构强度影响评估

Assessment of springing and whipping impact on structural strength of ice-breaking LNG ships

大型破冰型LNG船为兼顾敞水航行与破冰航行性能,通常船宽较大且船身较重,并采用异于常规LNG船的艏艉线型,这样船体可能遭受严重的波激振动和砰击颤振作用,对结构疲劳强度和船体梁极限强度产生较大影响。本文基于三维水弹性理论,研究波激颤振作用下的船体结构强度评估方法,对比破冰型极地LNG船与常规LNG船在敞水工况下波激颤振水弹性响应的差异,分析波激颤振作用对两型LNG船结构强度的影响。结果表明,波激颤振效应对结构强度影响显著,需在大型破冰型LNG船的设计检验中予以充分关注。

In order to balance the sailing performance in open water and polar regions,a large ice-breaking LNG carrier usually has a larger width and a heavier body,together with different characteristics of bow and stern shape from conventional ships,the hull may suffer serious springing and whipping response,which will have a huge impact on the structure fatigue strength and ultimate strength of hull girder.In this paper,based on three dimensional hydro-elastic theory,ship structural strength assessment including springing and whip-ping was studied,the differences of wave induced springing and whipping response between a large ice-breaking LNG ship and a conventional LNG ship under open water condition were compared,with analysis of the influence on the structural strength.The results show that the effect of springing and whipping on struc-tural strength is significant,to which more attention should be paid in the design and review of large ice-breaking LNG carriers.