When the ship is sailing in the sea,the static and dynamic loads acting on the independent type C tank transfers to the hull only through two saddles,and interactions in saddle area will bring high nonlinear char-acteristics to FEM research.In this paper,wood was modeled as solid elements,a series of interactions,con-straints and contacts were defined in ABAQUS,and nonlinear analysis method was used to reasonably simulate the nonlinear mechanical property and deformation feature of saddle area.Based on the difference of model range,two kinds of finite element methods of independent type C tanks were introduced:“Tank+Wood”model-ing method and “Tank+Wood+Hull”modeling method.The influence of the hull girder deformation in the ex-treme load case on tank strength were analyzed numerically through a calculation and it was shown that the hull girder deformation had a certain influence on tank strength,but tank strength depended basically on the local loads;the boundary effects on stresses results of tank structures in saddle area could be eliminated if ship struc-tures were considered in calculation model,and the stress level of this area was 3. 7%~16. 5% lower than the method ignoring the influence of ship structures.The numerical analysis results can be used for reference to choose an appropriate nonlinear tank analysis method in engineering practices.%船舶航行时独立C型液罐受到的动静载荷完全由两个鞍座传递给船体，对鞍座区域进行有限元模拟时涉及到接触问题因而具有高度的非线性，文中用体单元模拟层压木，并在ABAQUS中定义一系列接触、约束和连接器，采用非线性求解，较合理地模拟鞍座区域的受力和变形特点．基于模型范围的差异提出了两种独立C型液罐有限元分析方案：“罐体＋层压木”模型方案和“罐体＋层压木＋船体”模型方案．通过实例计算量化分析了船体在极端载荷工况下产生的船体梁变形对液罐强度的影响，分析比较表明：船体梁变形对液罐强度有一定的影响，但液罐强度整体上由局部载荷决定；在模型中考虑船体结构，能消除边界条件对鞍座区域液罐结构应力水平计算结果的影响，应力水平计算结果比不考虑船体结构影响的方案低3．7％～16．5％．此量化分析结果可为工程实际中合理选择液罐非线性有限元分析建模方案提供参考．
展开▼
