Parallel Free Stream Research Articles

Flow and Heat Transfer on a Continuous Flat Surface Moving in a Parallel Free Stream with Variable Fluid Properties

Boundary layer flow and heat transfer on a continuous flat surface moving in a parallel free stream with variable fluid properties are investigated. The similarity solution is used to transform the problem under consideration into a boundary value problem of coupled ordinary differential equations. Numerical results are carried out for various values of the dimensionless parameters of the problem. The results have demonstrated that the assumption of constant properties may introduce severe errors in the prediction of surface friction factor and heat transfer rate. For the same Reynolds numbers, Prandtl numbers, heating parameter, temperature exponents for viscosity and thermal conductivity parameters, and the same velocity difference |U w - U∞|, larger skin friction, and heat transfer coefficient results for U w > U∞ than for U w < U∞.

Heat transfer from a continuous surface in a parallel free stream of viscoelastic fluid

The effect of uniform suction or injection on flow and heat transfer from a continuous surface in a parallel free stream of viscoelastic second-order fluid is investigated. A perturbation method is used to obtain solutions for the transformed governing equations. The velocity profiles, temperature profiles, skin friction parameters and heat transfer parameters are computed for various values of the suction/injection parameter, λ.

Flow and heat transfer on a continuous flat surface moving in a parallel free stream of power-law fluid

Boundary layer solutions are presented to investigate the steady flow and heat transfer characteristics of a continuous flat surface moving in a parallel free stream of power-law fluid. The equations of motion are reduced to nonlinear ordinary differential equations by similarity transformations. These equations are solved numerically with double precision, using a procedure based on finite difference approximations. The results are presented for the distribution of velocity and temperature profiles within the boundary layer. The effects of the power-law index of fluid on the shear stress at the wall and the rate of heat transfer are studied. For the same generalised Reynolds and Prandtl numbers, power-law fluid parameter, and velocity difference ¦u w − u ∝¦ , a greater skin-friction and heat transfer coefficient result from u w > u ∝ than from u w < u ∝.

Mixed Convection from Vertical and Inclined Moving Sheets in a Parallel Freestream

Mixed Convection from Vertical and Inclined Moving Sheets in a Parallel Freestream

Boundary layer development on a continuous moving surface with a parallel free stream due to impulsive motion

Boundary layer development on a continuous moving surface with a parallel free stream due to impulsive motion

Boundary layer development on a continuous moving surface with a parallel free stream due to impulsive motion

The development of the momentum and thermal boundary layers over a semi-infinite flat plate has been studied when the external stream as well as the plate are impulsively moved with constant velocities. At the same time the temperature of the wall is suddenly raised from T∞, the temperature of the surrounding fluid, toT w and maintained at this temperature. The problem has been formulated in a new system of scaled coordinates such that fort⋆=0 it reduces to Rayleigh type of equation and fort⋆ → ∞ it reduces to Blasius or Sakiadis type of equation. A new scale of time has been used which reduces the region of integration from an infinite region to a finite region which reduces the computational time considerably. The governing singular parabolic partial differential equations have been solved numerically using an implicit finite difference scheme. For some particular cases, analytical solutions have been obtained. The results show that there is a smooth transition from Rayleigh solution to Blasius or Sakiadis solution as the dimensionless timeξ increases from zero to one. The shear stress at the wall is negative for the friction parameterλ 0.5 and zero forλ=0.5. The zero shear stress at the wall does not imply separation but corresponds to the parallel flow. The surface heat transfer is strongly dependent on the Prandtl numberPr and increases with it. Also forPr Pr0 it get reduced.

Momentum and heat transfer on a continuous flat surface moving in a parallel counterflow free stream

Heat transfer from a surface in motion relative to either a stationary or moving fluid occurs in many material processing applications such as hot rolling, extrusion, and drawing. In this study, an analysis has been carried out to predict transport occurring in the laminar boundary layer on a continuous surface which moves in the opposite direction of the free stream. Similarity and integral methods of solution were both used, and the results obtained are compared. Predictions for the local skin friction and heat transfer rate depend on the ratio of the surface and the free stream velocities and on the Prandtl number. When the velocity ratio is greater than zero, it was found that there is a Prandtl number for which the heat transfer rate is maximum.

Flow and heat transfer from a continuous surface in a parallel free stream of viscoelastic second-order fluid

Boundary layer solutions are presented to investigate the steady flow and heat transfer characteristics from a continuous flat surface moving in a parallel free stream of viscoelastic fluid. Numerical results are presented for the distribution of velocity and temperature profiles within the boundary layer. The effects of the viscoelastic parameter of the fluid on the shear stress at the wall and rate of heat transfer are studied. For the same Reynolds (based on the larger of the free stream and wall velocities) and Prandtl numbers and the same velocity difference |U w >∞|, larger skin-friction and heat transfer coefficient result for U w >∞ than for U w <∞.

Solidification on a Chilled Continuous Surface Moving in a Parallel Free Stream

Solidification on a Chilled Continuous Surface Moving in a Parallel Free Stream

Mixed convection from vertical and inclined moving sheets in a parallel freestream

Laminar mixed convection adjacent to vertical and inclined moving sheets in a parallel freestream is analyzed for both the uniform wall temperature and the uniform surface heat flux cases. The analysis covers the entire mixed convection regime, from pure forced convection to pure free convection. Numerical results are reported for different combinations of the velocities of the moving sheet us and the freestream u^ for Prandtl numbers of 0.7 and 7. Local Nusselt numbers as well as velocity and temperature distributions are presented for a wide range of the buoyancy* parameter. It is found that the local Nusselt number increases as the value of the buoyancy parameter increases. For the same dimensionless velocity difference \US— t£J, the local Nusselt number is larger for Us> U^ than it is for U^U^. Significant velocity overshoots occur within the boundary layer as the buoyancy parameter increases, with the low Prandtl number fluid exhibiting a more pronounced buoyancy effect than the high Prandtl number fluid. Simple correlations for evaluating local and average mixed convection Nusselt numbers are also presented and very good agreement is found between the computed results and the proposed simple correlations.

Flow and heat transfer from a continuous surface in a parallel free stream of micropolar fluid

Boundary layer solutions are presented to investigate the steady now and heat transfer characteristics from a continuous flat surface moving in a parallel free stream of micropolar fluid. Numerical results are presented for the distribution of velocity, micro-rotation and temperature profiles within the boundary layer. The groupings of the material properties of the fluid were allowed to vary over a wide range.

Boundary‐Layer Behavior on a Continuous Porous Flat Surface Moving in a Parallel Free Stream

ZAMM - Journal of Applied Mathematics and Mechanics / Zeitschrift für Angewandte Mathematik und MechanikVolume 66, Issue 11 p. 555-558 Short Communication Boundary-Layer Behavior on a Continuous Porous Flat Surface Moving in a Parallel Free Stream P. R. Chappidi, P. R. Chappidi Dept. of Mechanical Engineering & Aerospace Sciences and K. Vajravelu (author to be contacted for correspondence), Dept. of Mathematics, University of Central Florida, Orlando, Florida 32816, U.S.A.Search for more papers by this authorK. Vajravelu, K. Vajravelu Dept. of Mechanical Engineering & Aerospace Sciences and K. Vajravelu (author to be contacted for correspondence), Dept. of Mathematics, University of Central Florida, Orlando, Florida 32816, U.S.A.Search for more papers by this author P. R. Chappidi, P. R. Chappidi Dept. of Mechanical Engineering & Aerospace Sciences and K. Vajravelu (author to be contacted for correspondence), Dept. of Mathematics, University of Central Florida, Orlando, Florida 32816, U.S.A.Search for more papers by this authorK. Vajravelu, K. Vajravelu Dept. of Mechanical Engineering & Aerospace Sciences and K. Vajravelu (author to be contacted for correspondence), Dept. of Mathematics, University of Central Florida, Orlando, Florida 32816, U.S.A.Search for more papers by this author First published: 1986 https://doi.org/10.1002/zamm.19860661111Citations: 5AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Citing Literature Volume66, Issue111986Pages 555-558 RelatedInformation

Skin friction and heat transfer on a continuous flat surface moving in a parallel free stream

Comparaison des resultats obtenus par la methode d'analyse de couche limite et par la methode d'analyse de Navier-Stokes dans le calcul du frottement et du transfert de chaleur sur une surface plane en mouvement dans un ecoulement parallele libre de fluide