摘要:

A coupled finite-difference formulation is described for solving a reduced form of the compressible Navier-Stokes equations by a multiple space marching procedure. The properties of At equations are discussed and the solution algorithm presented. The scheme is used to compute incompressible flows by taking the incompressible limit(M ˜ 0.1) of the compressible formulation. A separate Poisson equation is not required for the pressure. Results are compared with experimental data and other numerical predictions for low Reynolds number channel inlet flow, flow over a rearward-facing step in a channel, and flow near the trailing edge of a flat plate.

ISSN:0149-5720    

DOI:10.1080/10407788608913534

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

A numerical study of non-Darcian natural convection in a vertical enclosure filled with a porous medium is performed. The flow is modeled using the Brinkman-Forchheimer-extended Darcy equations. The governing equations are solved with the SIMPLER algorithm and good agreement with previously reported numerical and experimental results is found. An order of magnitude analysis and the numerical results demonstrate the importance of non-Darcian effects. For high Darcy numbers (Da > 10−4), both extensions are of the same order of magnitude and must be used simultaneously. In addition, Forch-heimer's extension must be included for Pr ≤ 1.0 and all Darcy numbers. Finally, Nusselt number correlations are presented for three different ranges of the Darcy number covering wide ranges of the governing parameters.

ISSN:0149-5720    

DOI:10.1080/10407788608913535

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The problem of melting from a flat plate embedded in a porous medium is studied. The main focus is to determine the effect of natural convection flow in the liquid phase on the melting phenomenon. Two configurations an considered and modeled mathematically: a vertical plate and a horizontal plate. The final similarity equations art integrated numerically by use of the fourth-order Runge-Kutta method. Systematic “shooting” is required to satisfy the boundary conditions at infinity. Results are reported for the temperature and flow fields in the melt region. The melting phenomenon decreases the local Nusselt number at the solid-liquid interface.

ISSN:0149-5720    

DOI:10.1080/10407788608913536

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The equation of fluid motion for the steady flow in a double-walled concentric heat pipe with various distributions of evaporation and condensation has been solved numerically. The conditions in the condenser section are decidedly more complex. Reverse flows occur in the condenser section and occupy a substantial fraction of the condenser length for high condensation cooling rates. Pressure drops and hydrodynamic entrance lengths are presented for symmetric and asymmetric cases, and practical results of the calculation of pressure losses for low-speed vapor flows in the double-walled concentric heat pipe are given.

ISSN:0149-5720    

DOI:10.1080/10407788608913537

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The inverse heat conduction problem is one in which some of the slate variables are measured and the unknown heat fluxes are to be found. This paper describes the use of an eigenvalue analysis to reduce the order of the system in conjunction with dynamic programming, to estimate the heat fluxes. Several numerical experiments were performed on one- and two-dimensional problems to ascertain the effects of noise, weighting parameters, and reduction of modes on the solution.

ISSN:0149-5720    

DOI:10.1080/10407788608913538

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The steady local temperature distribution is determined for arbitrary conical systems with various boundary conditions. The temperature is derived for truncated conical sectors, where at the conical surface the temperature is kept constant and at the spherical surface a variable temperature distribution is imposed. The other case of constant temperature at the spherical surface and a variable temperature distribution at the conical surface is also treated. Some results are numerically evaluated, and the isothermal surfaces are presented.

ISSN:0149-5720    

DOI:10.1080/10407788608913539

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

ISSN:0149-5720    

DOI:10.1080/10407788608928205

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor