基于弹簧模型和节点密度插值的固体各向同性材料惩罚模型(Solid isotropic material with penalization,SIMP)方法,给出了一种用于多材料柔顺机构拓扑优化设计的分层优化方法。首先,以输出端位移最大化为目标以各种材料相应的体积占比...基于弹簧模型和节点密度插值的固体各向同性材料惩罚模型(Solid isotropic material with penalization,SIMP)方法,给出了一种用于多材料柔顺机构拓扑优化设计的分层优化方法。首先,以输出端位移最大化为目标以各种材料相应的体积占比为约束,建立了多材料柔顺机构拓扑优化模型;其次,采用节点密度插值,构造了设计区域内具有C^(0)连续性的密度场函数,给出了目标函数和约束的敏度解析表达式,使用过滤半径自适应迭代的敏度过滤方案,消除了节点密度插值法中的层化现象;再次,给出了一种分层优化策略用于求解多材料柔顺机构拓扑优化问题;最后,分别用典型的二维和三维柔顺机构拓扑优化问题验证了所提出方法的有效性,并分析了设计参数对优化结果的影响机制。展开更多
Node interpolation cell method（NICM）is a micromechanics method employing the virtual displacement principle and the representative volume element（RVE）scheme to obtain the relationship between the global and the lo...Node interpolation cell method（NICM）is a micromechanics method employing the virtual displacement principle and the representative volume element（RVE）scheme to obtain the relationship between the global and the local strain.Mechanical properties of 2-D textile fabric reinforced ceramic matrix composites are predicted by NICM.Microstructures of 2-D woven and braided fabric reinforced composite are modeled by two kinds of RVE scheme.NICM is used to predict the macroscopic mechanical properties.The fill and warp yarns are simulated with cubic B-spline and their undulating forms are approximated by sinusoid.The effect of porosity on the fiber and matrix are considered as a reduction of elastic module.The connection of microstructure parameters and fiber volume fraction is modeled to investigate the reflection on the mechanical properties.The results predicted by NICM are compared with that by the finite element method（FEM）.The comparison shows that NICM is a valid and feasible method for predicting the mechanics properties of 2-D woven and braided fabric reinforced ceramic matrix composites.展开更多
文摘基于弹簧模型和节点密度插值的固体各向同性材料惩罚模型(Solid isotropic material with penalization,SIMP)方法,给出了一种用于多材料柔顺机构拓扑优化设计的分层优化方法。首先,以输出端位移最大化为目标以各种材料相应的体积占比为约束,建立了多材料柔顺机构拓扑优化模型;其次,采用节点密度插值,构造了设计区域内具有C^(0)连续性的密度场函数,给出了目标函数和约束的敏度解析表达式,使用过滤半径自适应迭代的敏度过滤方案,消除了节点密度插值法中的层化现象;再次,给出了一种分层优化策略用于求解多材料柔顺机构拓扑优化问题;最后,分别用典型的二维和三维柔顺机构拓扑优化问题验证了所提出方法的有效性,并分析了设计参数对优化结果的影响机制。
基金Supported by the Aviation Science Foundationof China(2009ZB5052)the Specialized Research Foundation for the Doctor Program of Higher Education(20070287039)~~
文摘Node interpolation cell method（NICM）is a micromechanics method employing the virtual displacement principle and the representative volume element（RVE）scheme to obtain the relationship between the global and the local strain.Mechanical properties of 2-D textile fabric reinforced ceramic matrix composites are predicted by NICM.Microstructures of 2-D woven and braided fabric reinforced composite are modeled by two kinds of RVE scheme.NICM is used to predict the macroscopic mechanical properties.The fill and warp yarns are simulated with cubic B-spline and their undulating forms are approximated by sinusoid.The effect of porosity on the fiber and matrix are considered as a reduction of elastic module.The connection of microstructure parameters and fiber volume fraction is modeled to investigate the reflection on the mechanical properties.The results predicted by NICM are compared with that by the finite element method（FEM）.The comparison shows that NICM is a valid and feasible method for predicting the mechanics properties of 2-D woven and braided fabric reinforced ceramic matrix composites.
