船体板格极限强度的有限元计算方法应用广泛,但其计算方法具有一定的不稳定性,计算结果受多种因素的影响。本文针对船体板格有限元计算方法的不稳定性进行研究,通过将有限元计算结果与其他学者的研究成果进行对比,验证本文所采用的有限元方法的可靠性,然后针对板格材料、初始缺陷、网格密度、边界条件等几种因素的敏感性进行具体研究,发现理想应力应变关系会使得结果偏于危险。网格形状和网格密度对于结果均有影响,边界条件对于有限元结果有影响,最大误差在7.2%,并且模型3会使得结果偏于危险。初始缺陷是一敏感因素,最大误差在20%,因此需要根据实际缺陷选取合适的屈曲模态和比例因子。
The finite element method is widely used in hull panel ultimate strength, but it is instable in some degree. Calculation results are influenced by many factors. In this paper, the instability of finite element method for hull panel is studied. The reliability of the finite element method used in this paper is verified by comparing the results of finite element calculation results with other scholars. Then, the sensitivity of several factors, such as panel material, initial defect, mesh density and boundary condition, are studied. It is found that the ideal stress - strain relation will make the result dangerous, mesh shape and mesh density have influence for the results, the boundary conditions have an effect on the finite element results, the maximum error is 7.2%, and model three will make the results dangerous. Initial imperfection is a sensitive factor with a maximum error of 20%, so it is necessary to select the appropriate buckling modes and scale factors according to the actual defects.
2017,(): 48-53 收稿日期:2017-05-15
DOI:10.3404/j.issn.1672-7649.2017.11.010
分类号:U661.43
基金项目:国家自然科学基金资助项目(51679224);国家海洋局海洋可再生能源资金资助项目(GHME2016YY02);上海交通大学海洋工程国家重点实验室研究基金资助项目(1404);大学生创新创业训练计划资助项目(201710423123)
作者简介:冯亮(1983-),男,博士,讲师,研究方向为船舶与海洋工程结构强度评估
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