摘要:

A numerical investigation of the turbulent flow over a thin flat plate and wake region is reported. The finite analytic method is used to solve the partially parabolized Navier-Stokes equations using the k - ϵ turbulence model. The main focus of the present study is to develop a calculation method for an accurate prediction of the turbulent inner wake region when the wall function method is employed in the calculation of boundary layer on the plate at the upstream of wake. A wake function is introduced to accurately account for the large streamwise velocity gradient in the laminar wake region just downstream of the trailing edge of flat plate. It is similar to the wall function is used in the calculation of turbulent boundary layer near the wall. The computed results based on the combined wall and wake function were compared with the experimental data. The results showed good agreement with measured data.

ISSN:0149-5720    

DOI:10.1080/10407788808913652

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

Numerical solutions are given for the developing laminar mixed convection in a horizontal shrouded fin array. The governing equations for the three-dimensional parabolic flow have been numerically solved by a marching scheme. Detailed results are presented for the developing axial and secondary velocities, developing temperature profiles, local pressure gradient, and the Nusselt number. Computations are performed over a range of flow and geometric parameters. The results reveal that the buoyancy forces can have a significant influence on the fluid flow and heat transfer characteristics.

ISSN:0149-5720    

DOI:10.1080/10407788808913653

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

A numerical study is made of natural convection inside a horizontal cylinder with differentially heated ends. The geometric aspect ratio L/R is taken to be 2.0, and the Rayleigh number varies from 104to 107. The approach is based on primitive-variable finite differences discretized in generalized orthogonal coordinates. The governing equations are given in curvilinear orthogonal coordinates and the corresponding finite-difference control-volume formulation is presented. The resulting flow and temperature fields are compared to those known for other aspect ratios and Rayleigh numbers. Overall heat transfer data have also been obtained and compared with those from several approximate theories.

ISSN:0149-5720    

DOI:10.1080/10407788808913654

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

This paper is concerned with the numerical study of the heat transfer characteristics of the laminar mixing flow within a vertical channel. Free convection flows are induced by buoyant force from the subchannels and mix upward in the downstream main channel. The parabolic boundary layer equations are solved to obtain the velocity, temperature, and pressure distributions for the whole flow field, as well as Nusselt numbers along the plate walls. In the computation, the parallel side walls are considered isothermal and heating is symmetric. Results for both isothermal and isoflux central plate cases are presented. The mixing phenomena are investigated, and the influence of the central plate on the heat transfer performance is also evaluated.

ISSN:0149-5720    

DOI:10.1080/10407788808913655

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

Fluid flow and heat transfer in two-dimensional wavy channels of uniform cross-sectional area were analyzed numerically for constant-property laminar flow. The channel walls were maintained at constant temperature. Streamwise periodic geometry caused the flow and heat transfer to repeat periodically far downstream of the channel entrance. Computations were performed for different Reynolds numbers and geometric parameters. Prandtl number was kept constant (0.707). The whole solution domain was divided into five regions, and different coordinates were used for each region. The periodic boundary conditions were implemented by mutual replacements of field values at the two end regions. It was found that both Nusselt number and friction factor were greatly affected by Reynolds number and two geometric parameters.

ISSN:0149-5720    

DOI:10.1080/10407788808913656

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

The effect of thermal radiation on solidification of an absorbing, emitting, isotropically scattering finite, semitransparent gray medium bounded between two concentric cylinders is investigated. The law of conservation energy which employs enthalpy and temperature as dependent variables is coupled with a set of moment equations which are derived from the radiative transfer equation and Marshak-type boundary conditions by applying P-l differential approximation.

ISSN:0149-5720    

DOI:10.1080/10407788808913657

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

An implicit alternating direction (ADI) scheme is proposed here to solve the energy equation for the transient heat transfer to a fluid droplet suspended in an electric field. Use of Peaceman-Rachford scheme adopted by earlier authors produces undesirable oscillations in the Nusselt numbers which can be eliminated by the method proposed here.

ISSN:0149-5720    

DOI:10.1080/10407788808913658

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor