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Article
Publication date: 4 February 2021

Abdelraheem M. Aly and Zehba Raizah

The purpose of this study is to simulate the thermo-solutal convection resulting from a circular cylinder hanging in a rod inside a ∧-shaped cavity.

Abstract

Purpose

The purpose of this study is to simulate the thermo-solutal convection resulting from a circular cylinder hanging in a rod inside a ∧-shaped cavity.

Design/methodology/approach

The two dimensional ∧-shaped cavity is filled by Al2O3-water nanofluid and saturated by three different levels of heterogeneous porous media. An incompressible smoothed particle hydrodynamics (ISPH) method is adopted to solve the governing equations of the present problem. The present simulations have been performed for the alteration of buoyancy ratio (2N2), radius of a circular cylinder (0.05Rc0.3), a height of a rod (0.1Lh0.4), Darcy parameter (103Da105), Lewis number (1Le40), solid volume fraction (0ϕ0.06), porous levels (0η1=η21.5)and various boundary-wall conditions.

Findings

The performed numerical simulations indicated the importance of embedded shapes on the distributions of temperature, concentration and velocity fields inside ∧-shaped cavity. Increasing buoyancy ratio parameter enhances thermo-solutal convection and nanofluid velocity. Adiabatic conditions of the vertical-walls of ∧-shaped cavity augment the distributions of the temperature and concentration. Regardless the Darcy parameter, a homogeneous porous medium gives the lowest values of a nanofluid velocity.

Originality/value

ISPH method is used to simulate thermo-solutal convection of a nanofluid inside a novel ∧-shaped cavity containing a novel embedded shape and heterogeneous porous media.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 31 no. 11
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 9 October 2019

Bidemi Olumide Falodun and Adeola John Omowaye

This paper aims to address the problem of double-diffusive magnetohydrodynamics (MHD) non-Darcy convective flow of heat and mass transfer over a stretching sheet embedded in a…

Abstract

Purpose

This paper aims to address the problem of double-diffusive magnetohydrodynamics (MHD) non-Darcy convective flow of heat and mass transfer over a stretching sheet embedded in a thermally-stratified porous medium. The controlling parameters such as chemical reaction parameter, permeability parameter, etc., are extensively discussed and illustrated in this paper.

Design/methodology/approach

With the help of appropriate similarity variables, the governing partial differential equations are converted into ordinary differential equations. The transformed equations are solved using the spectral homotopy analysis method (SHAM). SHAM is a numerical method, which uses Chebyshev pseudospectral and homotopy analysis method in solving science and engineering problems.

Findings

The effects of all controlling parameters are presented using graphical representations. The results revealed that the applied magnetic field in the transverse direction to the flow gives rise to a resistive force called Lorentz. This force tends to reduce the flow of an electrically conducting fluid in the problem of heat and mass transfer. As a result, the fluid velocity reduces in the boundary layer. Also, the suction increases the velocity, temperature, and concentration of the fluid, respectively. The present results can be used in complex problems dealing with double-diffusive MHD non-Darcy convective flow of heat and mass transfer.

Originality/value

The uniqueness of this paper is the examination of double-diffusive MHD non-Darcy convective flow of heat and mass transfer. It is considered over a stretching sheet embedded in a thermally-stratified porous medium. To the best of the knowledge, a problem of this type has not been considered in the past. A novel method called SHAM is used to solve this modelled problem. The novelty of this method is its accuracy and fastness in computation.

Details

World Journal of Engineering, vol. 16 no. 6
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 26 September 2019

Muhammad Sohail, Rahila Naz and Rabeeah Raza

The purpose of this paper is to address the entropy analysis of the 3D flow of Maxwell nanofluid containing gyrotactic microorganism in the presence of homogeneous–heterogeneous…

Abstract

Purpose

The purpose of this paper is to address the entropy analysis of the 3D flow of Maxwell nanofluid containing gyrotactic microorganism in the presence of homogeneous–heterogeneous reactions with improved heat conduction and mass diffusion models over a stretched surface. Improved models are supported out by utilizing Cattaneo–Christov heat flux and generalized Fick’s law, respectively.

Design/methodology/approach

Governing equations which present the given flow phenomenon are modeled in the form of PDEs by applying boundary layer analysis and then suitable makeovers are engaged to transfigure prevailing partial differential equations into a set of ordinary differential equations. Transformed equations are handled via optimal homotopy analysis process in computational tool Mathematica and also a special case of already published work is substantiated and found to be in excellent settlement.

Findings

The bearing of innumerable convoluted physical parameters on velocity, temperature, concentration, reaction rate, the concentration of motile microorganism and entropy generation are presented and deliberated through graphs. Moreover, the convergence of the homotopic solution is presented in tabular form which confirms the reliability of the proposed scheme. It is perceived that mounting values of the magnetic parameter and Brinkman number boosts the irreversibility analysis and Bejan number diminishes for these parameters. Moreover, the growing values of Prandtl and Schmidt numbers reduce the temperature and concentration fields, respectively.

Practical implications

The work contained in this paper has applications in a different industry.

Originality/value

The work contained in this paper is original work and it is good for the researcher in the field of applied mathematics.

Details

Multidiscipline Modeling in Materials and Structures, vol. 16 no. 2
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 17 October 2018

A.S. Dogonchi, F. Selimefendigil and D.D. Ganji

The purpose of this study is to peruse natural convection in a CuO-water nanofluid-filled complex-shaped enclosure under the influence of a uniform magnetic field by using control…

Abstract

Purpose

The purpose of this study is to peruse natural convection in a CuO-water nanofluid-filled complex-shaped enclosure under the influence of a uniform magnetic field by using control volume finite element method.

Design/methodology/approach

Governing equations formulated in dimensionless stream function, vorticity and temperature variables using the single-phase nanofluid model with the Koo–Kleinstreuer–Li correlation for the effective dynamic viscosity and the effective thermal conductivity have been solved numerically by control volume finite element method.

Findings

Effects of various pertinent parameters such as Rayleigh number, Hartmann number, volume fraction of nanofluid and shape factor of nanoparticle on the convective heat transfer characteristics are analysed. It was observed that local and average heat transfer rates increase for higher value of Rayleigh number and lower value of Hartmann number. Among various nanoparticle shapes, platelets were found to be best in terms of heat transfer performance. The amount of average Nusselt number reductions was found to be different when nanofluids with different solid particle volume fractions were considered due to thermal and electrical conductivity enhancement of fluid with nanoparticle addition.

Originality/value

A comprehensive study of the natural convection in a CuO-water nanofluid-filled complex-shaped enclosure under the influence of a uniform magnetic field by using control volume finite element method is addressed.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 29 no. 5
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 21 January 2020

Ambreen A. Khan, S. Naeem, R. Ellahi, Sadiq M. Sait and K. Vafai

This study aims to investigate the effect of two-dimensional Darcy-Forchheimer flow over second-grade fluid with linear stretching. Heat transfer through convective boundary…

Abstract

Purpose

This study aims to investigate the effect of two-dimensional Darcy-Forchheimer flow over second-grade fluid with linear stretching. Heat transfer through convective boundary conditions is taken into account.

Design/methodology/approach

Nonlinear coupled governing equations are tackled with a homotopy algorithm, while for numerical computation the computer software package BVPh 2.0 is used. The convergence analysis is also presented for the validation of analytical and numerical results.

Findings

Valuation for the impact of key parameters such as variable thermal conductivity, Dufour and Soret effects and variable magnetic field in an electrically conducted fluid on the velocity, concentration and temperature profiles are graphically illustrated. It is observed from the results that temperature distribution rises by Dufour number whereas concentration distribution rises by Soret number. The Forchheimer number and porosity parameter raise the skin friction coefficient. The permeable medium has a vital impact and can help in reining the rate of heat transfer.

Practical implications

The permeable medium has a vital impact and can help in reining the rate of heat transfer.

Originality/value

To the best of the authors’ knowledge, this study is reported for the first time.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 9
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 22 December 2020

Saima Batool, Muhammad Nawaz and Mohammed Kbiri Alaoui

This study presents a mathematical approach and model that can be useful to investigate the thermal performance of fluids with microstructures via hybrid nanoparticles in…

Abstract

Purpose

This study presents a mathematical approach and model that can be useful to investigate the thermal performance of fluids with microstructures via hybrid nanoparticles in conventional fluid. It has been found from the extensive literature survey that no study has been conducted to investigate buoyancy effects on the flow of Maxwell fluid comprised of hybrid microstructures and heat generation aspects through the non-Fourier heat flux model.

Design/methodology/approach

Non-Fourier heat flux model and non-Newtonian stress–strain rheology with momentum and thermal relaxation phenomena are used to model the transport of heat and momentum in viscoelastic fluid over convectively heated surface. The role of suspension of mono and hybrid nanostructures on an increase in the thermal efficiency of fluid is being used as a medium for transportation of heat energy. The governing mathematical problems with thermo-physical correlations are solved via shooting method.

Findings

It is noted from the simulations that rate of heat transfer is much faster in hybrid nanofluid as compare to simple nanofluid with the increasing heat-generation coefficient. Additionally, an increment in the thermal relaxation time leads to decrement in the reduced skin friction coefficient; however, strong behavior of Nusselt number is shown when thermal relaxation time becomes larger for hybrid nanofluid as well as simple nanofluid.

Originality/value

According to the literature survey, no investigation has been made on buoyancy effects of Maxwell fluid flow with hybrid microstructures and heat generation aspects through non-Fourier heat flux model. The authors confirm that this work is original, and it has neither been published elsewhere nor is it currently under consideration for publication elsewhere.

Details

Multidiscipline Modeling in Materials and Structures, vol. 17 no. 3
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 28 January 2020

Mohamed Almakki, Hiranmoy Mondal and Precious Sibanda

This paper aims to investigate entropy generation in an incompressible magneto-micropolar nanofluid flow over a nonlinear stretching sheet. The flow is subjected to thermal…

Abstract

Purpose

This paper aims to investigate entropy generation in an incompressible magneto-micropolar nanofluid flow over a nonlinear stretching sheet. The flow is subjected to thermal radiation and viscous dissipation. The energy equation is extended by considering the impact of the Joule heating term because of an imposed magnetic field.

Design/methodology/approach

The flow, heat and mass transfer model are solved numerically using the spectral quasilinearization method. An analysis of the performance of this method is given.

Findings

It is found that the method is robust, converges fast and gives good accuracy. In terms of the physically significant results, the authors show that the irreversibility caused by the thermal diffusion the dominants other sources of entropy generation and the surface contributes significantly to the total irreversibility.

Originality/value

The flow is subjected to a combination of a buoyancy force, viscous dissipation, Joule heating and thermal radiation. The flow equations are solved numerically using the spectral quasiliearization method. The impact of a range of physical and chemical parameters on entropy generation, velocity, angular velocity, temperature and concentration profiles are determined. The current results may help in industrial applicants. The present problem has not been considered elsewhere.

Details

World Journal of Engineering, vol. 17 no. 1
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 22 June 2020

Naveed Imran, Maryiam Javed, Muhammad Sohail, S. Farooq and Mubashir Qayyum

Naturally, all the materials are not viscous (i.e. milk, mayonnaise, blood, vaccines, syrups, cosmetics, oil reservoirs, paints, etc.). Here present analysis focuses on the usage…

Abstract

Purpose

Naturally, all the materials are not viscous (i.e. milk, mayonnaise, blood, vaccines, syrups, cosmetics, oil reservoirs, paints, etc.). Here present analysis focuses on the usage of non-Newtonian fluid rheological properties enhancing, damping tools, protection apparatus individuals and in various distinct mechanical procedures. Industrial applications of non-Newtonian liquids include minimum friction, reduction in oil-pipeline friction, scale-up, flow tracers and in several others. The peristaltic mechanism is used as a non-Newtonian material carrier here. This mechanism occurs because of continuous symmetrical and asymmetrical propulsion of smooth channel walls. Peristalsis is a very significant mechanism for carrying drugs and other materials during sensitive diseases treatments.

Design/methodology/approach

Keeping in mind the considered problem assumptions (Rabinowitsch fluid model, thermal Grashof number, Prandtl number, density Grashof number, wall properties, etc.), it is found that the modeled equations are coupled and nonlinear. Thus here, analytical results are quite challenging to acquire and very limited to extremely venerated circumstances unsettled to their nonlinearity. Hence various developments found in computing proficiencies, numerical procedures that provides accurate, stable and satisfying solutions for non-Newtonian material flows exclusively in complex dimensions play a significant role. Here BVP4C numerical technique is developed to evaluate the nonlinear coupled system of equations with appropriate boundary constraints.

Findings

Due to convectively heated surface fluid between the walls having a small temperature. Sherwood and Nusselt numbers both deduce for fixed radiation values and different Rabinowitsch fluid quantity. Skin friction is maximum in the case of Newtonian, while minimum in case of dilatant model and pseudoplastic models. The influence of numerous parameters associated with flow problems such as thermal Grashof number, density Grashof number, Hartman number, Brownian motion, thermophoresis motion factor and slip parameters are also explored in detail and plotted for concentration profile, temperature distribution and velocity. From this analysis, it is concluded that velocity escalates for larger

Originality/value

The work reported in this manuscript has not been investigated so far by any researcher.

Details

Multidiscipline Modeling in Materials and Structures, vol. 17 no. 1
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 17 June 2019

Arif Hussain, Muhammad Yousaf Malik, Mair Khan and Taimoor Salahuddin

The purpose of current flow configuration is to spotlights the thermophysical aspects of magnetohydrodynamics (MHD) viscoinelastic fluid flow over a stretching surface.

Abstract

Purpose

The purpose of current flow configuration is to spotlights the thermophysical aspects of magnetohydrodynamics (MHD) viscoinelastic fluid flow over a stretching surface.

Design/methodology/approach

The fluid momentum problem is mathematically formulated by using the Prandtl–Eyring constitutive law. Also, the non-Fourier heat flux model is considered to disclose the heat transfer characteristics. The governing problem contains the nonlinear partial differential equations with appropriate boundary conditions. To facilitate the computation process, the governing problem is transmuted into dimensionless form via appropriate group of scaling transforms. The numerical technique shooting method is used to solve dimensionless boundary value problem.

Findings

The expressions for dimensionless velocity and temperature are found and investigated under different parametric conditions. The important features of fluid flow near the wall, i.e. wall friction factor and wall heat flux, are deliberated by altering the pertinent parameters. The impacts of governing parameters are highlighted in graphical as well as tabular manner against focused physical quantities (velocity, temperature, wall friction factor and wall heat flux). A comparison is presented to justify the computed results, it can be noticed that present results have quite resemblance with previous literature which led to confidence on the present computations.

Originality/value

The computed results are quite useful for researchers working in theoretical physics. Additionally, computed results are very useful in industry and daily-use processes.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 6
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 8 August 2019

Sadia Rashid, Tasawar Hayat, Sumaira Qayyum, Muhammad Ayub and Ahmed Alsaedi

The purpose of this paper is to examine outcome of activation energy in rotating flow of an Oldroyd-B nano liquid.

Abstract

Purpose

The purpose of this paper is to examine outcome of activation energy in rotating flow of an Oldroyd-B nano liquid.

Design/methodology/approach

Flow is generated due to stretched surface. Binary chemical reaction is studied. Brownian and thermophoresis effects are considered. The system of nonlinear ordinary differential equations is derived. Convergent series solutions are obtained by homotopy analysis method. The resulting expressions for velocities, temperature and concentration are computed for different embedded parameters.

Findings

It is found that velocities f′ and g  have decreasing effect when rotation parameter is enhanced. Brownian and thermophoresis are increasing functions of temperature and concentration. The physical quantities are sketched and discussed numerically. Concentration and temperature fields show decreasing behavior via Brownian and thermophoresis parameters.

Originality/value

Authors investigate the Rotating flow of Oldroyd-B nano fluid with chemical reactions. This work is not done yet in literature.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 29 no. 8
Type: Research Article
ISSN: 0961-5539

Keywords

1 – 10 of 16