本文采用基于谱分析法的直接计算法对某船舶结构进行疲劳强度评估。基于三维势流理论与北大西洋海况对该船舶进行水动力分析，得到了满载巡航工况下的波浪压力分布和舱段端面的水平弯矩、垂直弯矩、横向扭矩。同时根据船舶具体结构形式和数值计算的可行性对船体结构进行适当简化，并选用合适类型的单元对船舶结构进行离散，从而得到了船舶三舱段有限元模型。将波浪压力、惯性力、端面弯矩等载荷施加到舱段有限元模型上，得到了典型热应力点的疲劳强度应力值，然后通过谱分析法估算出疲劳寿命。研究结果可为该船舶初步设计阶段的结构优化提供有益参考和借鉴。
The fatigue strength assessment of navel ship was carried out using spectral-based approach. Hydrodynamic analysis was calculated based on 3-D potential theory and long term prediction using North Atlantic Ocean scatter diagram to obtain hydrodynamic pressure distribution, vertical bending moment, horizontal bending moment and torsion. Then this essay simplified the certain ship structure based on the ship's structure form and numerical analysis's purpose, building a finite element model of. three-cabin model. The design wave parameters and hydrodynamic pressure distribution were determined for typical load condition of the ship. And then leaded inertial force, obtained stress level, fatigue stress distribution and calculated fatigue life through spectral-based approach at last. The result of numerical analysis can provide effective basis and reference for fatigue strength assessment of ship at the stage of primary design.
2018,40(9): 32-38 收稿日期：2017-11-03
DOI：10.3404/j.issn.1672-7649.2018.09.006
分类号：U663.2
基金项目：国家自然科学基金青年资助项目（11402094，11502088）
作者简介：万松林(1974-),男,高级工程师,主要从事船舶与海洋结构物设计制造研究
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