基于热点应力的超规范油船疲劳强度分析

Analysis of Fatigue Strength for Supergauge Tankers based on Hot Spot Stress

为了方便清舱、减轻空船重量、提高货舱容积,对一艘7500DWT油船的舱壁结构做不设顶凳的超规范设计。基于JTP(双壳油船共同结构规范),运用热点应力法对该结构进行疲劳强度分析。应用有限元软件建立模型,并对热点位置精细化网格。采用数值计算模块计算不同工况下疲劳部位的热点应力。应用S-N曲线法计算出疲劳累积损伤并估算疲劳寿命,结果表明:该舱段结构疲劳寿命满足规范设计要求;在满足疲劳强度的前提下,舱壁无顶凳设计合理可行,并且具有一定的推广价值。

In order to clean hold easily,lighten empty ship and increase hold capacity,a super gauge design was proposed for a 7500DWT tanker with bulkheads of non-upper stool.Based on JTP(Joint Tanker Projet Common Structural Rules),the fatigue strength of this structure was analyzed by hot spot stress method.The model was set up by using finite element software and the hot spot part mesh was refined.The hot spot stress in different working conditions was calculated through numerical calculation module.The fatigue cumulative damage was calculated and the fatigue life was estimated by the method of S-N curve.The result showed that the fatigue life of the cargo hold met the standard and design requirements.The design of the bulkheads with no upper stools was reasonable and feasible,and it had some promotional values.