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振级落差约束下齿轮箱基座拓扑构型设计 总被引:3,自引:0,他引:3
采用结构拓扑优化理论,研究某新型齿轮箱基座拓扑构型设计方法.在满足指定振级落差设计要求下,进行底座和腹板材料拓扑布局动力学优化,减轻基座的重量.建立了两种拓扑构型优化模型:1)振级落差约束下,基座重量为目标函数,底座方钢(阻振质量)拓扑构型优化;2)振级落差约束下,基座重量为目标函数,腹板及底座方钢综合拓扑优化设计.通过两种方案的计算对比分析,得到给定约束条件下的减振效果良好的腹板和底座方钢结构拓扑形式,为实际工程设计应用提供概念设计.丰富新型减振基座拓扑构型设计理论和方法. 相似文献
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根据经典薄板理论,建立约束阻尼板有限元模型,将其视作镶嵌于无限大刚性障板,利用Rayleigh积分法推导结构的辐射声功率及灵敏度表达式。以一阶峰值频率或频带激励下的声功率最小化为目标,约束阻尼材料体积分数为约束条件,建立拓扑优化模型,采用渐进优化算法,编制了优化计算程序,获得了约束阻尼材料的最优拓扑构型,并与全覆盖板及基板的辐射声功率进行了对比。研究表明:以声功率最小化为目标,对约束阻尼材料布局进行拓扑优化,能有效抑制结构的振动声辐射,为结构低噪声设计提供了重要的理论参考和技术手段。 相似文献
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本文研究的是三维曲边区域上二阶椭圆型问题的等参有限元逼近。利用等参变换技巧和有限元插值理论,本文证明了等参有限元对于曲边区域边值问题具有最优收敛性,保证了等参有限元数值格式在工程应用中的可靠性和有效性。本文第二部分致力于构造简单有效的数值积分公式。文中给出的四点、五点、六点和八点六面体数值积分公式,可以简化单元刚度矩阵和荷载向量的计算,并严格证明了利用数值积分公式的等参元数值格式仍然保持最优收敛阶。 相似文献
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提出基于多评价点约束的零泊松比超材料功能基元拓扑优化设计方法。在同一功能基元拓扑基结构中,通过建立对于多个评价点的正、负泊松比约束,实现胞元零泊松比效应。分别采用最小质量和最大柔度目标函数拓扑优化模型优化设计出与半内六角蜂窝相似的零泊松比功能基元最优拓扑构型。提取功能基元最优构型并周期性序构了零泊松比超材料试件,通过有限元方法验证了该功能基元的零泊松比效应,并分析超材料试件的静、动力学特性。计算结果表明,最大柔度目标函数设计的功能基元构型的泊松比更接近于零,且具有更好的承载与隔振性能。设计了零泊松比超材料环肋双层圆柱壳结构,进行外壳静压和内部设备激振下壳体水下辐射噪声分析。研究表明,零泊松比超材料环肋可将外壳压缩变形转换为内外壳间环肋旋转,实现耐压壳内壳的保形,且具有较好的降噪性能。 相似文献
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《中国新技术新产品》2021,(2)
深水油田软管系统退役拆除时,不同的服役环境和软管系统构型需要设计不同的拆除回收工艺。该文依托国外某项目FSR(Free standing Riser)立管系统退役项目,介绍了FSR立管系统中的柔性跨接软管在湿存情况下的保护性回收工艺,其中包括软管产品设计构型简介、主要施工设备选型、施工设计、海上施工流程及主要注意事项等,为后续国内相关施工作业提供了参考。 相似文献
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L. L. THOMPSON P. M. PINSKY 《International journal for numerical methods in engineering》1996,39(10):1635-1657
A time-discontinuous Galerkin space–time finite element method is formulated for the exterior structural acoustics problem in two space dimensions. The problem is posed over a bounded computational domain with local time-dependent radiation (absorbing) boundary conditions applied to the fluid truncation boundary. Absorbing boundary conditions are incorporated as ‘natural’ boundary conditions in the space–time variational equation, i.e. they are enforced weakly in both space and time. Following Bayliss and Turkel, time-dependent radiation boundary conditions for the two-dimensional wave equation are developed from an asymptotic approximation to the exact solution in the frequency domain expressed in negative powers of a non-dimensional wavenumber. In this paper, we undertake a brief development of the time-dependent radiation boundary conditions, establishing their relationship to the exact impedance (Dirichlet-to-Neumann map) for the acoustic fluid, and characterize their accuracy when implemented in our space–time finite element formulation for transient structural acoustics. Stability estimates are reported together with an analysis of the positive form of the matrix problem emanating from the space–time variational equations for the coupled fluid-structure system. Several numerical simulations of transient radiation and scattering in two space dimensions are presented to demonstrate the effectiveness of the space–time method. 相似文献
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I. BABUKA J. M. MELENK 《International journal for numerical methods in engineering》1997,40(4):727-758
A new finite element method is presented that features the ability to include in the finite element space knowledge about the partial differential equation being solved. This new method can therefore be more efficient than the usual finite element methods. An additional feature of the partition-of-unity method is that finite element spaces of any desired regularity can be constructed very easily. This paper includes a convergence proof of this method and illustrates its efficiency by an application to the Helmholtz equation for high wave numbers. The basic estimates for a posteriori error estimation for this new method are also proved. © 1997 by John Wiley & Sons, Ltd. 相似文献
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利用有限元仿真技术对某型家用空调室外机管路进行了动力学分析,掌握了原始管路的模态及谐响应结果并根据结果对管路进行优化,从仿真及试验角度对优化管路进行了分析及试验验证,结果表明:采用仿真技术对室外机管路进行优化设计是可行的,取消管路用于减震的阻尼块、橡胶块,提高了管路质量一致性及可靠性。 相似文献
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该文针对杆系结构约束边界条件模型修正问题进行了研究。通过边界单元刚度矩阵的建立,将现有的子结构校正因子修正方法发展到边界条件的修正中。通过一种迭代的修正过程,仅用有限的低阶实测频率就可以实现对边界条件的修正。另外,该文提出了一种分步式整体修正方法,利用低阶不完备实测模态,实现对边界和上部结构的整体修正,有效地避免了修正方程组的病态问题。论文首先通过对悬臂梁有限元模型进行数值研究,验证了边界条件修正方法和分步式整体修正方法的正确性。最后通过悬臂梁物理模型试验,验证了方法的可行性。 相似文献
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Boundary element and finite element combination analysis on parallel schemes are improved in this paper. The conjugate gradient method (CG method) is introduced for renewal of unknowns on the combination boundary in place of the Schwarz method previously used, which makes it possible to determine a parameter required in the renewal iteration automatically. Further, the condense method is employed for higher efficiency of solution by reducing the number of degree of freedoms in both equations for the finite element and boundary element domains. Comparison of the present algorithm with the previous one in some numerical examples shows marked improvement in computational efficiency. 相似文献
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The paper describes a special finite element for three-dimensional, large displacement analysis of contact problems with slip and friction. This element may be used to model contact between several finite element bodies or contact between a finite element body and a flexible or rigid geometrical surface fixed in space or moving with time. The contact formulation is based on the concept of a spring-supported, moving disk that transfers normal contact forces and Coulomb friction forces. The contact surface has a finite, prescribed boundary.The contact element has been incorporated into the general-purpose, nonlinear, finite element program FENRIS. Three examples of its application are described in the paper.J. W. Simons was previously NTNF Fellow, Division of Technology, Trondheim, Norway 相似文献
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Ye Jianqiao 《Engineering Analysis with Boundary Elements》1992,9(4):283-287
This paper is concerned with the development of the mixed boundary element method and finite element method for the analysis of spherical annular shells under axisymmetric loads. The boundary element techniques are used to solve the equilibrium equation of shells and the central difference operator is adopted to deal with the compatibility equations. Iterative techniques are used throughout the analysis procedure. A number of numerical examples are given in the paper to illustrate the validity of the present approach. 相似文献