ISSN:0748-8025    

DOI:10.1002/cnm.1630020602

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractA highly accurate finite difference method is developed for the classical wave equation in one spatial dimension. The derivation uses the ‘modified equaiton’ approach, whereby the partial differential equation actually solved by the finite difference equation is determined. By investigating the largest error terms, the new method is compared with the standard explicit method and a method developed by Twizell.2Theoretical conclusions have been verified by using the methods to solve a simple problem for which an exact solution is availa

ISSN:0748-8025    

DOI:10.1002/cnm.1630020603

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractA modification of MacCormack's finite difference scheme is applied to a one‐dimensional problem of plane wave propagation resulting from the sudden application of stress to the surface of a linear viscoelastic solid half‐space. A further modification is proposed which uses results from a wavefront expansion. Numerical results are presented which indicate the effect of the Courant number on numerical instability and numerical dispersion with, and without, the modification based on the wavefront expansion resu

ISSN:0748-8025    

DOI:10.1002/cnm.1630020604

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractThe object of this study is to predict the peak values of the stress resultants and couples in a relatively thick cylindrical shell under a concentrated local loading in order to guide the design of a large‐scale reinforced concrete test specimen. Four finite element programs, SHORE‐III, two versions of RONALD, and ANSYS, were employed here. The SHORE‐III and RONALD analyses considered a complete cantilevered cylinder, while the ANSYS model treated a cylindrical panel free along the curved edge and constrained in various ways along the longitudinal edge. Comprehensive comparative results are provided for the linear elastic loading case, which indicate the magnitude and attenuation of concentrated loading effects on cylindrical shells and p

ISSN:0748-8025    

DOI:10.1002/cnm.1630020605

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractAn improved version of the Rayleigh techinique used by Rayleigh and Schmidt for solid mechanics problems is extended to one‐ and two‐dimensional problems of steady heat conduction. Here the technique is applied to the heat‐balance integral (HBI) method, the variational method and the square‐error method. To determine the most appropriate value of the non‐integer exponent, either one of two different criteria is used: the variational or the square‐error integral. Thus, four new methods are considered. A comparison with a closed‐form solution is made for a one‐dimensional fin. It is demonstrated that the error for a one‐term trial function is much less for an improved HBI method with the variational integral criterion. Thus, additional terms should not be needed in most instances. Excellent results are also achieved by using one of the new methods in a two‐dimensional problem with inter

ISSN:0748-8025    

DOI:10.1002/cnm.1630020606

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractA fourth‐order convergent finite difference method is developed for the numerical solution of the nonlinear fourth‐order boundary value problemy(iv)(x) =f(x,y),a

ISSN:0748-8025    

DOI:10.1002/cnm.1630020607

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractA rapidly converging relaxation technique for the parabolized Navier–Stokes equation has been devised. The scheme is applicable in both supersonic and subsonic flows, but it is discussed here in the context of supersonic flows. The upstream propagating acoustic influence in the subsonic part of the flow is introduced semi‐implicitly through the streamwise momentum equation applied on the body, and through a forward‐differencing on the streamwise pressure gradient term in the interior. This procedure yields a new boundary condition on the energy in the total energy equation. The presser‐velocity system in the subsonic layer is coupled, but the positive time‐like marching characteristic of the governing equations is still maintained. The relaxation technique is demonstrated to work for a three‐dimensional flow over a cone‐flare in supe

ISSN:0748-8025    

DOI:10.1002/cnm.1630020608

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractA computational method is presented for solving linear singularly perturbed two‐point boundary value problems with a boundary layer on the left end of the interval. The original problem is divided into inner and outer region problems. The reduced problem is solved to obtain the terminal boundary condition. Then, a new inner region problem is created and solved as a two‐point boundary value problem (TPBVP). In turn, the outer region problem is also solved as a TPBVP. Both these problems (TPBVPs) are efficiently solved by employing a fourth order finite difference scheme. The proposed method is iterative on the terminal point. Some numerical examples have been included to demonstrate the applicability of the met

ISSN:0748-8025    

DOI:10.1002/cnm.1630020609

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractThe problem of membrane locking for curved elements is discussed in detail. The penalty technique is used to develop a locking free curved beam element based on the Marguerre's relations. This formulation is then generalized to nonlinear analyses using updated Lagrangian description. Some examples are presented to assess the efficiency of the proposed model.

ISSN:0748-8025    

DOI:10.1002/cnm.1630020610

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractA description is given of the regularization method of numerical differentiation. The method is compared with the recent method of McNamee, and is shown to perform well, especially with very noisy data. A FORTRAN program is also given.

ISSN:0748-8025    

DOI:10.1002/cnm.1630020611

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY