摘要:

AbstractThe viscous incompressible rotating flow in a shrouded rotor geometry is solved by the finite element method, using the complete three‐dimensional (axisymmetric) Navier‐Stokes equations. Solutions to classical as well as to previously unsolved rotating flow problems are given and discus

ISSN:0029-5981    

DOI:10.1002/nme.1620170802

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractA triangular element is developed using a complete third‐degree polynomial as the interpolation function. The nodal variables include the function and its first‐order derivatives. A local continuity condition, which implements the conservation of the normal gradients of the interpolation function along the three boundaries of the element, is provided as a remedy for the nonconformity of the first‐order derivatives in conventionalC° elements. The element is applied to potential flow problems. Numerical results for the flow over a cylinder and the flow through a draft tube elbow of a hydraulic turbine confirm the validity and the accuracy of this new cubic element. A comparison of this element with aC° triangular element is made by checking their differences from an analytical solution for the flow over the cylinder. This element appears to be more accurate than theC°

ISSN:0029-5981    

DOI:10.1002/nme.1620170803

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractThe extension of a combined finite element‐transfer matrix method to problems governed by quasi‐harmonic equations is presented.Particular emphasis is given to heat conduction, and numerical results are presented for this type of problem (steady and transient cases).The principal advantage of the method with respect to finite elements concerns the minor dimension of the last matrix formulation which quite often implies a reduced computational burden.The accuracy of the method is considered by comparing the numerical results with some available analytical solutions for slabs: an excellent agreement is effectively obtained.No particular restrictions to the application of the method exist, and quite complex systems may be considered, provided that a suitable subdivision into strips and elements of the relevant region is carried

ISSN:0029-5981    

DOI:10.1002/nme.1620170804

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractA parametric infinite element is presented for solving axisymmetric problems under non‐axisymmetric forcing functions where the considered domain is assumed infinite. The element accuracy is compared against the exact solution for two classical problems: Boussinesq's and Cerruti's. Boussinesq's problem for a rigid circular plate is also presented. For these problems, using relatively simple displacement functions, the element provides a reasonable infinite domain representatio

ISSN:0029-5981    

DOI:10.1002/nme.1620170805

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractThe paper demonstrates that Fredholm integral equations of the first kindwith the kernelK(x,s)=(x–s)k/[1+(x–s)2]noccur while solving problems of synthesis of electrostatic and magnetic fields. Numerical results for the solution of one of the equations obtained by the regularization method are provided, with two ways of regularization being employed—that of Tikhonov and that of Lavr

ISSN:0029-5981    

DOI:10.1002/nme.1620170806

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractIn this paper, free surface flow problems involving large free surface motion are analysed using finite element techniques. In solving these problems a spatially fixed Eulerian mesh is employed, in conjunction with a moving Lagrangian free surface line. The coupling, between the equations valid on the free surface and the equations valid on the fluid domain, is carried out using hybrid finite element techniques. Physical problems involving solitary wave propagation, sloshing dynamics and porous media flow are analysed to demonstrate the developed technique.

ISSN:0029-5981    

DOI:10.1002/nme.1620170807

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractNumerical integration of the system of governing equations which define a boundary value problem written down in the form of a coupled system of first‐order ordinary differential equations is shown to be a powerful technique. After presenting the basic approach the paper critically examines the numerical schemes available for situations when the boundary value problem so defined has boundary layer characteristics. One such method which is originally due to Goldberg, Setlur and Alspaugh3is described in detail, with documentation in the form of a flow diagram and a FORTRAN listing of a working subroutine. The method is shown to be computationally efficient and reliable for the solution of a class of problems in the field of solid mechanics. Potential use of the method for the solution of magnetostatic problems is indicate

ISSN:0029-5981    

DOI:10.1002/nme.1620170808

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractA numerical procedure developed for solving the two‐dimensional elastic contact problems with friction is presented. This is a generalization of a procedure developed by Francavilla and Zienkiewicz to include frictional effects under proportionate loading. The method uses the flexibility matrix obtained by inversion of condensed stiffness matrix formed by eliminating all the nodes except those where contact is likely to take place and those with external forces. Compatibility of displacements for both normal and tangential directions is applied to those nodes which do not slip. However, for the nodes which slip, compatibility of displacements is applied for normal direction only and slip condition is applied in the tangential direction. The technique has been applied to several problems and very good results have been obtained. The number of iterations needed are very smal

ISSN:0029-5981    

DOI:10.1002/nme.1620170809

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractWe present two self‐contained programs which have given excellent results for uniform approximation of functions (or discrete data) by generalized rational functions. The first program is an extension of a program published in 1975 which uses a linear programming approach known as the differential correction algorithm. The present version is more robust, and allows for the use of a multiplicative weight function and restrictions on the values of the approximating function. These features make the program more suitable for applications such as digital filter approximation. The second program uses a combination of the Remes and differential correction algorithms which combines some of the good features of both algorithms. Given here is a discussion of the algorithms together with several examples. A FORTRAN listing can be obtained from the first autho

ISSN:0029-5981    

DOI:10.1002/nme.1620170810

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY

ISSN:0029-5981    

DOI:10.1002/nme.1620170811

出版商:John Wiley&Sons, Ltd    

年代:1981

数据来源: WILEY