基于综合裕度的AUV环肋圆柱壳多目标优化设计

Multi-objective Optimization Design of Auv Ring-stiffened Cylindrical Shell Based on Comprehensive Margin

针对自主水下机器人耐压壳体结构多目标优化设计问题,首先构建环肋圆柱壳整体参数化有限元初始模型,计算非线性临界屈曲载荷,以该值与一阶特征值屈曲载荷之比作为折减因子。然后基于折减因子法建立临界载荷裕度,以综合应力裕度、临界载荷裕度和质量为优化目标,采用NSGA-Ⅱ算法对模型在耐压和起吊工况下进行优化计算,基于博弈组合赋权-TOPSIS排序法得到最优设计尺寸。分析结果表明,优化后各裕度均有减小,壳体重量减轻,材料得到充分利用。最后进行了耐压壳体起吊、压力测试和海上试验,验证了建模及优化方法的有效性。

For the multi-objective optimization design problem of the pressure hull structure of autonomous underwater robots,the initial parameterized finite element model of the ring-stiffened cylindrical shell is constructed firstly,and the nonlinear critical buckling load is calculated.The ratio of this value to the first-order eigenvalue buckling load is used as the reduction factor.Then,the critical load margin is established based on the reduction factor method.And comprehensive stress margin,critical load margin and mass are selected as the optimization objectives.The NSGA-Ⅱalgorithm is used for model optimizing under pressure and lifting conditions.The optimal design size is obtained using the game combination weighting TOPSIS ranking method.The analysis results show that all margins and shell weight are reduced after optimization,and the material is fully utilized.Finally,the lifting test,pressure test,and sea trial are conducted to verify the effectiveness of the modeling and optimization methods.