摘要:

AbstractThe Richardson extrapolation method, which produces a 4th‐order‐accurate solution on a subgrid by combining 2nd‐order solutions on the fine grid and the subgrid, is ‘completed’ – in the sense that a higher‐order‐accurate solution is produced on all the f

ISSN:1069-8299    

DOI:10.1002/cnm.1640090502

出版商:John Wiley&Sons, Ltd    

年代:1993

数据来源: WILEY

摘要:

AbstractIt is known that the boundary‐element coefficient matrices in steady‐state elastodynamics are frequency‐dependent. For a multifrequency run, the coefficient matrices have to be reformed at each different frequency. This procedure usually involves heavy numerical integration, and hence is very time consuming. In this paper, two interpolation schemes are initially introduced to accelerate the process of matrix reformation without sacrificing the solution accuracy. In the first scheme, the coefficient matrices are first slightly transformed and then interpolated in the frequency domain. In the second scheme, the Green function is interpolated in the spatial domain. Comparison between these two schemes both in terms of accuracy and efficiency is presented. Finally, a hybrid scheme that takes advantage of the best of both interpolation schemes is proposed. Numerical examples are given to demonstrate the three different interpolation sc

ISSN:1069-8299    

DOI:10.1002/cnm.1640090503

出版商:John Wiley&Sons, Ltd    

年代:1993

数据来源: WILEY

摘要:

AbstractAp‐type finite‐element scheme is introduced for Navier‐Stokes problems in a fully coupled stream function/vorticity formulation. The resulting coupled non‐linear system is solved using a Newton iteration with incremental continuation in the Reynold's number. A biconjugate gradient (BCG) scheme in an element‐by‐element setting is applied to solve the linearized system at each Newton iteration. Pseudo‐element block preconditioners produce a practical PBCG method, even for ill‐conditioned systems arising from high‐pelements in the case of Stokes flow. The problem at higher Reynolds number

ISSN:1069-8299    

DOI:10.1002/cnm.1640090504

出版商:John Wiley&Sons, Ltd    

年代:1993

数据来源: WILEY

摘要:

AbstractIn the present paper numerical solutions of the one‐dimensional Burger equation are obtained. The technique of finitely reproducing non‐linearities introduced by Bazley is used. This technique when applied to Burger's equation gives a method where a system of non‐linear ordinary differential equations is to be solved. The present method produces very accurate results in comparison to finite‐difference of finite‐elemen

ISSN:1069-8299    

DOI:10.1002/cnm.1640090505

出版商:John Wiley&Sons, Ltd    

年代:1993

数据来源: WILEY

摘要:

AbstractAn efficient wave input procedure in the finite and infinite element coupled model is presented in this paper. Compared to the previous wave input method, the main advantage of the present wave input procedure lies in its computational efficiency because only a small region of the medium needs to be modelled by finite elements. The equivalence between the present wave input procedure and the previous one has been theoretically proven when a harmonic wave propagates vertically in an isotropic homogeneous elastic half‐space. In addition, the accuracy of the present wave input method has been evaluated based on the solutions obtained for SH‐wave, SV‐wave and P‐wave scattering problems in a semicircular canyon for which analytical solutions are already av

ISSN:1069-8299    

DOI:10.1002/cnm.1640090506

出版商:John Wiley&Sons, Ltd    

年代:1993

数据来源: WILEY

摘要:

AbstractA 12‐DOF quadrilateral element for plate bending is formulated based on the concept of generalized compatibility and semi‐Loof constraints. The element DOFs are defined with the conventional displacements at corner nodes and the semi‐Loof constraints are used in the formulation. This element is a generalized conforming one which passes Irons' patch test and can be used to solve problems with complicated boundaries. When overall considerations of simplicity, accuracy and reliability are taken into account, this new element is one of the best 12‐DOF quadrilateral plate‐bending elements currently

ISSN:1069-8299    

DOI:10.1002/cnm.1640090507

出版商:John Wiley&Sons, Ltd    

年代:1993

数据来源: WILEY

摘要:

AbstractThis paper focuses on how parameter changes in a vibration system expressed by a discrete eigenvalue problem affect vibration modes in the special case of closely spaced eigenvalues, i.e. ‘eigenvalue clusters’. For this class of problems, a perturbation analysis is developed that can be used to compute changes in eigenvalues and eigenvectors in response to small parameter changes. The analysis is applied to a 6‐degree‐of‐freedom spring‐mass system containing a single pair of closely spaced

ISSN:1069-8299    

DOI:10.1002/cnm.1640090508

出版商:John Wiley&Sons, Ltd    

年代:1993

数据来源: WILEY

摘要:

AbstractThe classical Gauss–Laguerre quadrature rule for the semi‐infinite integration interval [0,∞] is modified and applied to the case of the weight function exp(‐x)/xcorresponding to finite‐part (or, equivalently, hypersingular) integrals. The new set of orthogonal polynomials is constructed and it is seen to consist of linear combinations of the classical Laguerre polynomials with appropriately determined coefficients. The zeros of these modified Laguerre polynomials are seen to be distinct, but one of these lies outside the integration interval. Formulae for the corresponding weights are also given and numerical values and results are presented. The present results generalize the corresponding results for the finite interval [0,1] to semi‐infinite intervals and they are applicable to a variety of applied mechanics and related problems, where finite‐part integrals appear in

ISSN:1069-8299    

DOI:10.1002/cnm.1640090509

出版商:John Wiley&Sons, Ltd    

年代:1993

数据来源: WILEY

ISSN:1069-8299    

DOI:10.1002/cnm.1640090510

出版商:John Wiley&Sons, Ltd    

年代:1993

数据来源: WILEY

ISSN:1069-8299    

DOI:10.1002/cnm.1640090501

出版商:John Wiley&Sons, Ltd    

年代:1993

数据来源: WILEY