针对复杂产品方案设计中的关联约束可拓推理问题，本研究提出了一种基于可拓本体相关网的复杂产品方案设计可拓推理模型。首先，建立了复杂产品方案设计可拓本体模型，并进行了可拓本体相关性分析; 其次，通过领域知识获得产品方案设计方
向，建立可拓本体特征的可拓关联函数，并基于信息模型建立可拓本体相关网; 然后，给出了基于可拓本体相关网的方案设计可拓推理算法，通过进行设计方向多层级灰关联聚类分析和基于可拓本体相关网的关联度计算分析，进而获得满足设计需求的初始产品设计方案。最后，通过水轮机设计实例对文中的模型和算法进行了说明和验证分析，结果表明了模型和算法的有效性和可行性。

An extensional reasoning model for complex product scheme design based on extension ontology correla-tion related network was put forward to solve the extension reasoning issue of relevant constraints in complex pro-duct scheme design． Firstly，an extensional ontology model for complex product scheme design was constructed，and the relativity of extensional ontology was analyzed． Secondly，the direction of product scheme design was obtained through domain knowledge，and the extension correlation function of extension ontology features was pro-posed． The extensional ontology correlation network was constructed based on the information model． Then，an extension reasoning algorithm for scheme design based on extensional ontology related network was presented． The initial product design scheme meeting design requirements was obtained through multi-level grey relational cluste-ring analysis of design direction and relational degree calculation analysis based on extensional ontology related net-works． Finally，the models and the algorithms were illustrated and validated by a design case of hydro turbine． The results show that the models and the algorithms are effective and feasible．