知识工程在船舶结构优化设计中的应用

针对船舶结构设计变量是涉及多种设计和约束条件的离散变量,造成结构优化的高度非线性、多峰性等问题,而且设计过程中需要设计规范和专家经验等知识支持,结合其具有很强的综合性、模糊性等特点,提出了基于知识工程的船舶结构优化设计方法。该方法利用知识工程与结构优化相结合,将获取的设计知识构建知识库应用于船舶结构优化设计,并通过知识工程技术实现参数化结构模型与优化数学模型的相互转化,降低结构优化设计对用户知识水平的要求。水密横舱壁结构的优化设计算例表明,满足约束要求的情况下,其结构重量在优化后比优化前降低了,保证了结构性能合理的同时实现重量最轻的目标;将结构参数化模型和数学优化模型结合在一起,为设计经验少的设计者提供了一种结构设计的捷径;实现了从不同资源中获取知识并应用于优化设计过程,促进设计能力的提高,降低优化设计过程对知识和经验的依赖。

Application of knowledge-based engineering for ship structure optimization design

Ship structural design variables are discrete variables involving a variety of design requirements and constraints,which leads to highly nonlinear,multimodal and other problems in structure optimization.Besides,it needs design regulations and experts experience to support ship structure design.Considering its highly comprehensive,empirical,fuzzy and other characteristics,this paper presents application of knowledge-based engineering(KBE)for ship structure optimization design method.This method combines the principle of KBE design with structure optimization design.It constructs knowledge base including design regulations and expert experience for structure initial design.In addition,it can achieve the mutual transformation of parameterized structure model and optimization mathematical model by KBE.The example of watertight transverse bulkhead optimization design shows the optimized weight of structure is lower than before on the condition of meeting constrains required.It ensures the reasonable structure performance and lightest weight goal.Secondly,it combines structure parameterized model with mathematical optimization model,which provides a shortcut for designer with less experience of structure design.In conclusion,it gets knowledge from different source and applies for structure optimization design,improve the design level and reduce the designers’ dependence on the knowledge and experience.