摘要:

AbstractFinite element predictions of two‐dimensional laminar natural convection in a partially divided rectangular cavity at high Rayleigh number are presented. The walls are differentially heated, the horizontal surfaces are insulated and the cavity contains a partial vertical divider which is centrally located and whose height is varied. Detailed results are presented for an aluminium half‐divider in water for Rayleigh number up to 1011and compared directly with recent experiments in a cavity of aspect ratio 1/2. The predicted flow and heat transfer are in good agreement with the measurements and confirm the existence of a high Rayleigh number regime with characteristic behaviour that differs significantly from that found at lower Rayleigh number. In addition, the effects of the divider height, the divider conductivity, the fluid Prandtl number and the cavity aspect ratio are studied. The results show that a direct simulation of the complex flow and heat transfer that occurs in partially divided cavities is possible for realistic physical conditi

ISSN:0271-2091    

DOI:10.1002/fld.1650080302

出版商:John Wiley&Sons, Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractIn this paper we present a new version of the ‘modified finite element method’ (MFEM) presented by Gresho, Chan, Lee and Upson.1The main modification of the original algorithm is the introduction of a cost‐effective and memory‐saving iterative solver for the discretized Poisson equation for the pressure. The vectorization of the preconditioner has been especially considered. For low Prandtl number problems we also split the advection‐diffusion operator of the energy equation into explicit and implicit parts. In that sense the present approach is related to the recent implicitization of the diffusive terms introduced by Gresho and Chan2and by Gresho.3The algorithm is applied to the study of buoyancy‐driven flow oscillations occuring in a horizontal crucible of molten metal under the action of a horizontal temperatu

ISSN:0271-2091    

DOI:10.1002/fld.1650080303

出版商:John Wiley&Sons, Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractA numerical finite volume prediction method for arbitrary‐shaped passages has been applied to the case of fully developed axial turbulent flow past a rod eccentrically placed in a circular tube. The numerical method was based on an orthogonal curvilinear mesh and employed an algebraic stress transport model to calculate the full three‐dimensional velocity field directly from the governing partial differential equations. This study is one of a series of applications of this prediction method to a range of different non‐circular passages that have been made in order to establish the capabilities and usefulness of this type of procedure. The present eccentric rod case was the subject of a comprehensive experimental investigation by Kacker1which has enabled a detailed comparison to be made between the present predictions and the measurements. This comparison included local distributions of axial velocity, wall shear stress and secondary velocities; and although found to be satisfactory overall, some differences in detail revealed possible shortcomings in the measurement of secondary flow. This, together with other previously reported cases, indicates, that, although the present method cannot be expected to replace experiment in providing turbulent passage flow data, it has an important role to play in interpreting and supplementing experi

ISSN:0271-2091    

DOI:10.1002/fld.1650080304

出版商:John Wiley&Sons, Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractThe flux‐vector splitting method is applied to the convective part of the steady Navier‐Stokes equations for incompressible flow. By the use of partial upwind differences in the split first‐order part and central differences in the second‐order part, a set of discrete equations is obtained which can be solved by vector variants of classical relaxation schemes. It is shown that accurate results can be obtained on one of the GAMM backward‐facing step test

ISSN:0271-2091    

DOI:10.1002/fld.1650080305

出版商:John Wiley&Sons, Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractNumerical solutions are presented for two‐dimensional low Reynolds number flow in a rotating tank with stationary barriers. The boundary element method is employed, assuming straight panels and quadratic source distribution. The feasibility of repositioning the nodes as a way to minimize the error is explored. A stretching parameter places smaller elements near the re‐entrant regions. Elementary error analysis shows uniform improvement in the solution with stretching. The changing eddy pattern for different numbers and sizes of the barriers is compared with experimental resu

ISSN:0271-2091    

DOI:10.1002/fld.1650080306

出版商:John Wiley&Sons, Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractThe paper presents a two‐dimensional model for the investigation of pressure transients in pipelines. The governing equations have been established and a method of solving the equations using the centre implicit method is presented. The theoretically predicted values are compared with the experimentally determined pressure transients for horizontal pipelines with a valve at the end. The two‐dimensional model gives results which are accurate than those of the one‐dimensional model and are in good agreement with the experimental re

ISSN:0271-2091    

DOI:10.1002/fld.1650080307

出版商:John Wiley&Sons, Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractIn this paper a total linearization method is derived for solving steady viscous free boundary flow problems (including capillary effects) by the finite element method. It is shown that the influence of the geometrical unknown in the totally linearized weak formulation can be expressed in terms of boundary integrals. This means that the implementation of the method is simple. Numerical experiments show that the iterative method gives accurate results and converges very fast.

ISSN:0271-2091    

DOI:10.1002/fld.1650080308

出版商:John Wiley&Sons, Ltd    

年代:1988

数据来源: WILEY

ISSN:0271-2091    

DOI:10.1002/fld.1650080309

出版商:John Wiley&Sons, Ltd    

年代:1988

数据来源: WILEY

ISSN:0271-2091    

DOI:10.1002/fld.1650080310

出版商:John Wiley&Sons, Ltd    

年代:1988

数据来源: WILEY

ISSN:0271-2091    

DOI:10.1002/fld.1650080301

出版商:John Wiley&Sons, Ltd    

年代:1988

数据来源: WILEY