针对用有限元法进行连续体结构拓扑优化时需不断重构网格来处理网格畸变和网格移动,且存在数值计算不稳定等问题,基于无网格径向点插值方法(Radial Point Interpolation Method,RPIM)对简谐激励下的连续体结构进行拓扑优化.选取节点的...针对用有限元法进行连续体结构拓扑优化时需不断重构网格来处理网格畸变和网格移动,且存在数值计算不稳定等问题,基于无网格径向点插值方法(Radial Point Interpolation Method,RPIM)对简谐激励下的连续体结构进行拓扑优化.选取节点的相对密度作为设计变量,以结构动柔度最小化为目标函数,基于带惩罚的各向同性固体微结构(Solid Isotropic Microstructure with Penalization,SIMP)模型建立简谐激励下的优化模型;采用伴随法求解得到目标函数的敏度分析公式;利用优化准则法求解优化模型.经典的二维连续体结构拓扑优化算例证明该方法的可行性和有效性.展开更多
In this paper, using Hamilton principle, the control equation of fluid-structure interaction vibration of a pipe conveying fluid under simple harmonic excitation was established and a novel method, Galerkin-Modality'...In this paper, using Hamilton principle, the control equation of fluid-structure interaction vibration of a pipe conveying fluid under simple harmonic excitation was established and a novel method, Galerkin-Modality' s method was proposed to solve this equation. The influence of the damp, the flow velocity, the pressure and the length of the pipe supported by simple supports on the piping' s first two natural frequencies was discussed. The criti- cal pressure and the critical length of the pipe were obtained. The influence of the flow velocity and pressure on the piping's maximal relative displacements were analyzed.展开更多
针对关于结构动响应拓扑优化问题的研究较少、有限元分析软件的拓扑优化模块无法实现的问题,采用变密度法研究连续体结构在基础简谐激励下的动响应拓扑优化.将基础简谐激励下的响应控制问题归结为结构在体积约束下目标点响应幅值最小化...针对关于结构动响应拓扑优化问题的研究较少、有限元分析软件的拓扑优化模块无法实现的问题,采用变密度法研究连续体结构在基础简谐激励下的动响应拓扑优化.将基础简谐激励下的响应控制问题归结为结构在体积约束下目标点响应幅值最小化的优化模型;推导有阻尼结构在基础简谐激励下目标点响应幅值的灵敏度公式;采用变密度法求解该优化问题.采用多项式惩罚模型解决带惩罚的各向同性固体微结构(Solid Isotropic Microstructure with Penalization,SIMP)模型带来的附属效应现象;采用灰度过滤方法改善经典变密度法在优化过程中灰度单元收敛过慢的问题,从而减少变密度法优化的迭代步数并且使优化结果更清晰.以平面悬臂板模型为例,验证该优化方法对目标点响应幅值的优化以及灰度过滤函数对优化迭代的改善.展开更多
文摘针对用有限元法进行连续体结构拓扑优化时需不断重构网格来处理网格畸变和网格移动,且存在数值计算不稳定等问题,基于无网格径向点插值方法(Radial Point Interpolation Method,RPIM)对简谐激励下的连续体结构进行拓扑优化.选取节点的相对密度作为设计变量,以结构动柔度最小化为目标函数,基于带惩罚的各向同性固体微结构(Solid Isotropic Microstructure with Penalization,SIMP)模型建立简谐激励下的优化模型;采用伴随法求解得到目标函数的敏度分析公式;利用优化准则法求解优化模型.经典的二维连续体结构拓扑优化算例证明该方法的可行性和有效性.
基金supported by National High Technology Research and Development Program of China Under Grant No.2007AA04Z404Natural Science Basic Research Plan in Shaanxi Province of China Under Grant No.SJ08A17+1 种基金Technical Innovation Foundation of Northwestern Polytechnical University(NWPU) Under Grant No.2008KJ02019the "111" Project of NWPU Under Grant No.B07050
文摘In this paper, using Hamilton principle, the control equation of fluid-structure interaction vibration of a pipe conveying fluid under simple harmonic excitation was established and a novel method, Galerkin-Modality' s method was proposed to solve this equation. The influence of the damp, the flow velocity, the pressure and the length of the pipe supported by simple supports on the piping' s first two natural frequencies was discussed. The criti- cal pressure and the critical length of the pipe were obtained. The influence of the flow velocity and pressure on the piping's maximal relative displacements were analyzed.
文摘针对关于结构动响应拓扑优化问题的研究较少、有限元分析软件的拓扑优化模块无法实现的问题,采用变密度法研究连续体结构在基础简谐激励下的动响应拓扑优化.将基础简谐激励下的响应控制问题归结为结构在体积约束下目标点响应幅值最小化的优化模型;推导有阻尼结构在基础简谐激励下目标点响应幅值的灵敏度公式;采用变密度法求解该优化问题.采用多项式惩罚模型解决带惩罚的各向同性固体微结构(Solid Isotropic Microstructure with Penalization,SIMP)模型带来的附属效应现象;采用灰度过滤方法改善经典变密度法在优化过程中灰度单元收敛过慢的问题,从而减少变密度法优化的迭代步数并且使优化结果更清晰.以平面悬臂板模型为例,验证该优化方法对目标点响应幅值的优化以及灰度过滤函数对优化迭代的改善.