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Article
Publication date: 20 September 2011

Azizah Mohd Rohni, Syakila Ahmad and Ioan Pop

The purpose of this paper is to theoretically investigate the steady two‐dimensional boundary‐layer flow past a moving semi‐infinite flat plate in a water‐based nanofluid…

Abstract

Purpose

The purpose of this paper is to theoretically investigate the steady two‐dimensional boundary‐layer flow past a moving semi‐infinite flat plate in a water‐based nanofluid containing three different types of nanoparticles: copper (cuprum) Cu, alumina (aluminium oxide) Al2O3, and titania (titanium dioxide) TiO2. The effects of moving parameter λ as well as solid volume fraction parameter φ on the flow and heat transfer characteristics are studied. Taking into account the rising demands of modern technology, including chemical production, power stations and microelectronics, there is a need to develop new types of fluids that will be more effective in terms of heat exchange performance.

Design/methodology/approach

A similarity transformation is used to reduce the governing partial differential equations to a set of nonlinear ordinary differential equations which are then solved numerically using Keller‐box method.

Findings

There is a region of unique solutions for λ>0, however, multiple (dual) solutions exist for λc<λ≤0 and no solutions for λ<λc<0. A reverse flow is formed when λ<0.

Research limitations/implications

The solutions can be obtained up to a certain value of the moving parameter (critical value or turning point). The boundary layer separates from the plate beyond the turning point hence it is not possible to get the solution based on the boundary‐layer approximations after this point. To obtain further solutions, the full Navier‐Stokes equations have to be solved.

Originality/value

The present results are original and new for the boundary‐layer flow and heat transfer of a moving flat plate in a nanofluid. Therefore, this study would be important for the scientists and engineers in order to become familiar with the flow behaviour and properties of such nanofluids, and the way to predict the properties of this flow for the process equipments.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 21 no. 7
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 3 July 2018

Santosh Chaudhary and Mohan Kumar Choudhary

The purpose of this paper is to investigate two-dimensional viscous incompressible magnetohydrodynamic boundary layer flow and heat transfer of an electrically conducting…

Abstract

Purpose

The purpose of this paper is to investigate two-dimensional viscous incompressible magnetohydrodynamic boundary layer flow and heat transfer of an electrically conducting fluid over a continuous moving flat surface considering the viscous dissipation and Joule heating.

Design/methodology/approach

Suitable similarity variables are introduced to reduce the governing nonlinear boundary layer partial differential equations to ordinary differential equations. A numerical solution of the resulting two-point boundary value problem is carried out by using the finite element method with the help of Gauss elimination technique.

Findings

A comparison of obtained results is made with the previous work under the limiting cases. Behavior of flow and thermal fields against various governing parameters like mass transfer parameter, moving flat surface parameter, magnetic parameter, Prandtl number and Eckert number are analyzed and demonstrated graphically. Moreover, shear stress and heat flux at the moving surface for various values of the physical parameters are presented numerically in tabular form and discussed in detail.

Originality/value

The work is relatively original, as very little work has been reported on magnetohydrodynamic flow and heat transfer over a continuous moving flat surface. Viscous dissipation and Joule heating are neglected in most of the previous studies. The numerical method applied to solve governing equations is finite element method which is new and efficient.

Details

Engineering Computations, vol. 35 no. 4
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 5 March 2018

Assunta Andreozzi

The purpose of this paper is to analyze the thermal and fluid dynamic behaviors of mixed convection in air because of the interaction between a buoyancy flow and a moving

Abstract

Purpose

The purpose of this paper is to analyze the thermal and fluid dynamic behaviors of mixed convection in air because of the interaction between a buoyancy flow and a moving plate induced flow in a horizontal no parallel-plates channel to investigate the effects of the minimum channel spacing, wall heat flux, moving plate velocity and converging angle.

Design/methodology/approach

The horizontal channel is made up of an upper inclined plate heated at uniform wall heat flux and a lower adiabatic moving surface (belt). The belt moves from the minimum channel spacing section to the maximum channel spacing section at a constant velocity so that its effect interferes with the buoyancy effect. The numerical analysis is accomplished by means of the finite volume method, using the commercial code Fluent.

Findings

Results in terms of heated upper plate and moving lower plate temperatures and stream function fields are presented. The paper underlines the thermal and fluid dynamic differences when natural convection or mixed convection takes place, varying minimum channel spacing, wall heat flux, moving plate velocity and converging angle.

Research limitations/implications

The hypotheses on which the present analysis is based are two-dimensional, laminar and steady state flow and constant thermo physical properties with the Boussinesq approximation. The minimum distance between the upper heated plate of the channel and its lower adiabatic moving plate is 10 and 20 mm. The moving plate velocity varies in the range 0-1 m/s; the belt moves from the right reservoir to the left one. Three values of the uniform wall heat flux are considered, 30, 60 and 120 W/m2, whereas the inclination angle of the upper plate θ is 2° and 10°.

Practical implications

Mixed convection because of moving surfaces in channels is present in many industrial applications; examples of processes include continuous casting, extrusion of plastics and other polymeric materials, bonding, annealing and tempering, cooling and/or drying of paper and textiles, chemical catalytic reactors, nuclear waste repositories, petroleum reservoirs, composite materials manufacturing and many others. The investigated configuration is used in applications such as re-heating of billets in furnaces for hot rolling process, continuous extrusion of materials and chemical vapor deposition, and it could also be used in thermal control of electronic systems.

Originality/value

This paper evaluates the thermal and velocity fields to detect the maximum temperature location and the presence of fluid recirculation. The paper is useful to thermal designers.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 28 no. 3
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 8 February 2022

Iskandar Waini, Umair Khan, Aurang Zaib, Anuar Ishak and Ioan Pop

This study aims to investigate the micropolar fluid flow through a moving flat plate containing CoFe2O4-TiO2 hybrid nanoparticles with the substantial influence of…

Abstract

Purpose

This study aims to investigate the micropolar fluid flow through a moving flat plate containing CoFe2O4-TiO2 hybrid nanoparticles with the substantial influence of thermophoresis particle deposition and viscous dissipation.

Design/methodology/approach

The partial differential equations are converted to the similarity equations of a particular form through the similarity variables. Numerical outcomes are computed by applying the built-in program bvp4c in MATLAB. The process of flow, heat and mass transfers phenomena are examined for several physical aspects such as the hybrid nanoparticles, micropolar parameter, the thermophoresis particle deposition and the viscous dissipation.

Findings

The friction factor, heat and mass transfer rates are higher with an increment of 1.4%, 2.2% and 1.4%, respectively, in the presence of the hybrid nanoparticles (with 2% volume fraction). However, they are declined because of the rise of the micropolar parameter. The imposition of viscous dissipation reduces the heat transfer rate, significantly. Meanwhile, thermophoresis particle deposition boosts the mass transfer. Multiple solutions are developed for a certain range of physical parameters. Lastly, the first solution is shown to be stable and reliable physically.

Originality/value

As far as the authors have concerned, no work on thermophoresis particle deposition of hybrid nanoparticles on micropolar flow through a moving flat plate with viscous dissipation effect has been reported in the literature. Most importantly, this current study reported the stability analysis of the non-unique solutions and, therefore, fills the gap of the study and contributes to new outcomes in this particular problem.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 32 no. 10
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 16 September 2013

Abdul Rahman Mohd Kasim, Zarith Sofiah Othman, Sharidan Shafie and Ioan Pop

The purpose of this paper is to study the Blasius flat plate with viscous dissipation in the presence of suction or injection effects in the boundary layer of a…

Abstract

Purpose

The purpose of this paper is to study the Blasius flat plate with viscous dissipation in the presence of suction or injection effects in the boundary layer of a viscoelastic fluid.

Design/methodology/approach

The governing partial differential equations are derived as a first order ordinary differential equation using similarity (Blasius) variables. Velocity profiles, temperature profiles, skin friction parameters, and heat transfer parameters are computed numerically for various values of the viscoelastic parameter K, the suction or injection parameter f w , the Prandtl number Pr, the Eckert number Ec, and the moving parameter λ.

Findings

The effects of the viscoelastic, moving, and suction/injection parameters on the skin friction and heat transfer of the flat plate are studied. The effects of these parameters on the velocity and temperature profiles are also presented for 0≤Pr≤3.

Originality/value

To the best of the authors' knowledge, this important classical problem has not been studied before for the case of a viscoelastic fluid. Thus, the results are original and new for this type of fluid.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 23 no. 7
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 7 June 2013

M. Ferdows, Jashim Uddin, Mohammad Mehdi Rashidi and N. Rahimzadehc

The paper aims to consider non‐viscous, laminar mixed convection boundary‐layer flow over a horizontal moving porous flat plate, with chemical reaction.

Abstract

Purpose

The paper aims to consider non‐viscous, laminar mixed convection boundary‐layer flow over a horizontal moving porous flat plate, with chemical reaction.

Design/methodology/approach

The governing equations are expressed in non‐dimensional form and the series solutions of coupled system of equations are constructed for velocity, temperature and concentration functions using numerical method.

Findings

The investigated parameters are: buoyancy parameter, chemical reaction parameter, order of chemical reaction, Prandtl number and Schmidt number.

Originality/value

The partial differential equations are transformed to ordinary differential equations. The method of one parameter continuous group theory is used for this transformation.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 23 no. 5
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 6 June 2016

Ammar Mushtaq, M. Mustafa, T. Hayat and A. Alsaedi

– The purpose of this paper is to consider a laminar two-dimensional incompressible flow of an electrically conducting fluid over a moving flat plate with a parallel free stream.

Abstract

Purpose

The purpose of this paper is to consider a laminar two-dimensional incompressible flow of an electrically conducting fluid over a moving flat plate with a parallel free stream.

Design/methodology/approach

The governing equations are first reduced into self-similar forms and then solved for the numerical solutions by shooting method.

Findings

The results are compared with the available studies is some special cases and found in excellent agreement. It is noticed that an increase in the magnetic field strength leads to a decrease in the momentum boundary layer thickness and enhancement in the rate of heat transfer from the plate. It is also observed that temperature and heat transfer from the plate increase when radiation effect is strengthened.

Originality/value

A recently proposed idea of nonlinear radiative heat transfer with Joule heating and viscous dissipation effects is analyzed.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 26 no. 5
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 28 May 2020

Mahantesh M. Nandeppanavar, M.C. Kemparaju, R. Madhusudhan and S. Vaishali

The steady two-dimensional laminar boundary layer flow, heat and mass transfer over a flat plate with convective surface heat flux was considered. The governing nonlinear…

Abstract

Purpose

The steady two-dimensional laminar boundary layer flow, heat and mass transfer over a flat plate with convective surface heat flux was considered. The governing nonlinear partial differential equations were transformed into a system of nonlinear ordinary differential equations and then solved numerically by Runge–Kutta method with the most efficient shooting technique. Then, the effect of variable viscosity and variable thermal conductivity on the fluid flow with thermal radiation effects and viscous dissipation was studied. Velocity, temperature and concentration profiles respectively were plotted for various values of pertinent parameters. It was found that the momentum slip acts as a boost for enhancement of the velocity profile in the boundary layer region, whereas temperature and concentration profiles decelerate with the momentum slip.

Design/methodology/approach

Numerical Solution is applied to find the solution of the boundary value problem.

Findings

Velocity, heat transfer analysis is done with comparing earlier results for some standard cases.

Originality/value

100

Details

Multidiscipline Modeling in Materials and Structures, vol. 16 no. 5
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 3 June 2014

Minakshi Poonia and R. Bhargava

The purpose of this paper is to deal with the study of free convection magnetohydrodynamic (MHD) boundary layer flow of an incompressible viscoelastic fluid along an…

Abstract

Purpose

The purpose of this paper is to deal with the study of free convection magnetohydrodynamic (MHD) boundary layer flow of an incompressible viscoelastic fluid along an inclined moving plate and heat transfer characteristics with prescribed quadratic power-law surface temperature.

Design/methodology/approach

The governing partial differential equations are transformed into non-dimensional, non-linear coupled ordinary differential equations which are solved numerically by robust Galerkin finite element method.

Findings

Numerical results for the dimensionless velocity and temperature profiles are displayed graphically for various physical parameters such as viscoelasticity, Prandtl number, angle of inclination parameter, magnetic and buoyancy parameter. The local Nusselt number is found to be the decreasing function of magnetic field parameter whereas it increases with increasing values of Prandtl number, viscoelastic parameter and buoyancy parameter.

Practical implications

The present problem finds significant applications in MHD power generators, cooling of nuclear reactors, thin film solar energy collector devices.

Originality/value

The objective of this work is to analyze the heat transfer of convective MHD viscoelastic fluid along a moving inclined plate with quadratic power law surface temperature. An extensively validated, highly efficient, variation finite element code is used to study this problem. The results are validated and demonstrated graphically.

Details

Multidiscipline Modeling in Materials and Structures, vol. 10 no. 1
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 4 January 2019

Abhishek Kumar Singh, A.K. Singh and S. Roy

The purpose of the present study is to analyze the mixed convection water boundary layer flows over moving vertical plate with variable viscosity and Prandtl number. The…

Abstract

Purpose

The purpose of the present study is to analyze the mixed convection water boundary layer flows over moving vertical plate with variable viscosity and Prandtl number. The non-linear partial differential equation governing the flow and thermal fields are presented in non-dimensional form by using appropriate transformation. The quasi-linearization technique in combination with implicit finite difference scheme has been adopted to solve the nonlinear-coupled partial differential equation. The numerical results are displayed graphically to illustrate the influence of various non-dimensional physical parameters on velocity and temperature. Further, the numerical results for local skin-friction coefficient and local Nusselt number are also reported. The present findings are compared with previously reported results, and these comparisons are found to be in excellent agreement.

Design/methodology/approach

The nonlinear partial differential equations governing the flow and thermal fields have been solved numerically using the implicit finite difference scheme in combination with the quasi-linearization technique. The numerical results are presented in terms of skin friction and heat transfer rate which are useful in determining the surface heat requirements for stabilizing the laminar boundary layer flow over a moving plate in water.

Findings

The effect of the ratio of free-stream velocity to the composite reference velocity is significant on the velocity profile. Near the wall region, as ratio of free stream velocity to composite reference velocity increases form 0.1 to 0.5, the velocity overshoot gets enhanced from 3 per cent to 41 per cent. The influence of buoyancy parameter and ration of free stream velocity to composite reference velocity on temperature profile is comparatively less than on velocity profiles. The increase in the skin friction coefficient is dependent on the increase in the value of ratio of free stream velocity to composite reference velocity if the buoyancy parameter λ is fixed and vice versa and increases in ΔT results in a decrease in N and Pr.

Originality/value

The present investigation is to deal with the solution of steady laminar water boundary layer flows over a moving plate with temperature-dependent viscosity and Prandtl number applicable for water using practical data. The fluid considered here is water, as it is one of the most common working fluids found in engineering applications.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 29 no. 2
Type: Research Article
ISSN: 0961-5539

Keywords

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