摘要:

AbstractIn this paper, a general finite‐element (FE) formulation has been developed for natural frequency analysis of spatial rod systems. Accordingly, the frequency analysis of spatially curved and pretwisted rods, with either constant or varying cross‐section on distributed elastic or point supports has been carried out. First, an appropriate finite‐element equation is developed utilizing the governing equations (equations of motion, kinematical relations and constitutive relations) of a spatial rod. The time‐dependent governing equations are then solved to find the modal shapes as well as the natural frequencies of the discretized system. The master element, developed herein, comprises 12 degrees of freedom (six at each end) and contains the rigid body motion as well as the deformation modes. This element has the generality of embodying the special cases of prismatic, curved and pretwisted elements, both with either linear or constant curvature changes. To verify the formulations several numerical examples are pr

ISSN:0748-8025    

DOI:10.1002/cnm.1630060602

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

摘要:

AbstractTwo‐dimensional Stokes flow of an incompressible Newtonian fluid about a horizontal cylinder situated next to a moving wall is presented and suggested as a non‐trivial benchmark problem. Both the primitive variable Galerkin finite‐element and the exact solutions are generated on a sequence of refined meshes; error norms and convergence rates are presented for the C0bilinear‐velocity/C−1piece‐wise constant‐pressure and the C0biquadratic‐velocity/C−1linear‐pressure qua

ISSN:0748-8025    

DOI:10.1002/cnm.1630060603

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

摘要:

AbstractUsing a natural body‐fitted co‐ordinate system, based on the streamlines, incompressible potential flow over an axisymmetric body at zero incidence is formulated as a Dirichlet boundary‐value problem for the unknown co‐ordinater(x, ψ). Flow over various body shapes is computed using a finite‐difference scheme and SLOR, on both uniform and clustered grids. The results show excellent agreement with previous researchers. The coding is very simple, the formulation can be extended to compressible flows and can also be used to solve the inver

ISSN:0748-8025    

DOI:10.1002/cnm.1630060604

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

摘要:

AbstractFor the single‐step time‐integration algorithm formulated by Zienkiewiczet al., a weight function of the formtris posed. The weight parameters θ are found through a simple formula for a range of valuesr. These are used to integrate three numerical formulations of the non‐linear dynamics equation for a planar pendulum. Comparisons with existing integration methods show that, forrnon‐positive, ther‐methods are accurate, stable and very competitive. Results are dependent both uponrand the formulation. Useful ranges forrare

ISSN:0748-8025    

DOI:10.1002/cnm.1630060605

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

ISSN:0748-8025    

DOI:10.1002/cnm.1630060606

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

摘要:

AbstractIt is often necessary to impose linear constraints on solutions obtained with the finite‐element method. This can be done by the penalty method or by eliminating dependent variables. The penalty method requires the careful selection of a penalty parameter and may lead to an inexact imposition of the constraints. Elimination is preferable because it is exact. The zero rows that elimination generates in the coefficient matrix can be removed by reducing the order of the matrix, or by adding back the constraints. The latter approach has the advantage of keeping the imposition of constraints separate from matrix assembly. However, straightforward addition of multi‐point constraint equations destroys the symmetry of the matrix. A new method of adding the constraints preserves matrix symme

ISSN:0748-8025    

DOI:10.1002/cnm.1630060607

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

摘要:

AbstractA spline finite‐strip method capable of analysing the buckling of prismatic thin‐walled structural members under arbitrary loading is presented. It utilizes cubic B3splines as displacement functions in the longitudinal direction and polynomials in the transverse direction. Numerical integration is used to determine the geometric stiffness matrix of the strips. Two examples which demonstrate the accuracy and versatility of the method are presen

ISSN:0748-8025    

DOI:10.1002/cnm.1630060608

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

ISSN:0748-8025    

DOI:10.1002/cnm.1630060610

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

ISSN:0748-8025    

DOI:10.1002/cnm.1630060611

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

ISSN:0748-8025    

DOI:10.1002/cnm.1630060612

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY