摘要:

AbstractA class of second‐derivative two‐step methods, S(2), with order 5 and depending on two parameters – which are used to adapt the stability region while minimizing the truncation error coefficient – is constructed. An analysis of two subclasses of S(2)–A(0) stable methods and methods with finite stability interval ‐ with their stability and accuracy properties is presented. Numerical examples are al

ISSN:0748-8025    

DOI:10.1002/cnm.1630080602

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractA method for the solution of 3‐D parabolic problems on multi‐connected regions is presented. The domain discretization is automatic: at first the boundary is approximated by means of polyhedra; subsequently a Cartesian orthogonal non‐uniform grid is generated. The differential operator is discretized by a Crank‐Nicolson scheme, coupled with general finite‐difference formulae (GFDF).Some test problems are presented to show the efficiency of t

ISSN:0748-8025    

DOI:10.1002/cnm.1630080603

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractAn investigation is conducted on the performance of the curved isoparametric cubic beam element for analysing vibrational behaviour of coil springs. Firstly, the results of full and uniformly reduced integration are compared for three static problems. Uniformly reduced integration is shown to yield surprising accuracy, even for curved and pretwisted beams. In the latter case of a shear loaded cantilever beam, exact internal force values are obtained. Since element geometry is described by nodal co‐ordinates and cross‐sectional orientation only, the element proves to be ideal for modelling both helical and non‐helical sections of coil springs. In addition, the formulation is easy to implement and simpler than those of previous ‘helical spring elements’. It is shown that accurate values for modal frequencies can be obtained with relatively coar

ISSN:0748-8025    

DOI:10.1002/cnm.1630080604

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractIn this paper the issue of invariance for various hybrid/mixed models with and without incompatible displacement modes is addressed. Special emphasis is directed to assumed spaces of the primary variables which are based on the natural co‐ordinates. It is found that if the assumed spaces of all primary variables are invariant to orthogonal transformations, any derived models would automatically be invariant. In contrast to the traditional concept of choosing the starting stress/strain interpolants based on either global or local co‐ordinate systems, it is shown that it is not necessary to employ either complete or balanced polynomial expansions of natural co‐ordinates in order to preserve the element invariance. Based on one of the newly proposed classes of stress/strain interpolants, 8–node invariant‐assumed stress brick elements are proposed which are close to Loikkanen and Irons' assumed stress counterpart of Wilson's Q6bric

ISSN:0748-8025    

DOI:10.1002/cnm.1630080605

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

摘要:

AbstractA novel solver for natural convection flows based on the boundary integral equation method is presented here. The solver can be used to obtain flow solutions in arbitrary 2–D geometries with modest computational effort. Both the vorticity and thermal transport equations are treated as modified Helmholtz equations and solved using boundary integral methods. The non‐linear inertial terms partially manifest themselves as volume sources which are computed iteratively using a method of characteristics approach. The buoyancy term is treated as a volume vorticity source. Rapid computation of the volume fields at each iteration level is achieved by precomputing the influence coefficient matrices. Results are presented for flow in a cavity driven by both shear and buoya

ISSN:0748-8025    

DOI:10.1002/cnm.1630080606

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

ISSN:0748-8025    

DOI:10.1002/cnm.1630080607

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY

ISSN:0748-8025    

DOI:10.1002/cnm.1630080601

出版商:John Wiley&Sons, Ltd    

年代:1992

数据来源: WILEY