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Article
Publication date: 6 June 2016

B Mahanthesh, B J Gireesha and R S R Gorla

The purpose of this paper is to numerically solve the problem of an unsteady squeezing three-dimensional flow and heat transfer of a nanofluid in rotating vertical channel…

Abstract

Purpose

The purpose of this paper is to numerically solve the problem of an unsteady squeezing three-dimensional flow and heat transfer of a nanofluid in rotating vertical channel of stretching left plane. The fluid is assumed to be Newtonian, incompressible and electrically conducting embedded with nanoparticles. Effect of internal heat generation/ absorption is also considered in energy equation. Four different types of nanoparticles are considered, namely, copper (Cu), alumina (Al2O3), silver (Ag) and titanium oxide (TiO2) with the base fluid as water. Maxwell-Garnetts and Brinkman models are, respectively, employed to calculate the effective thermal conductivity and viscosity of the nanofluid.

Design/methodology/approach

Using suitable similarity transformations, the governing partial differential equations are transformed into set of ordinary differential equations. Resultant equations have been solved numerically using Runge-Kutta-Fehlberg fourth fifth order method for different values of the governing parameters. Effects of pertinent parameters on normal, axial and tangential components of velocity and temperature distributions are presented through graphs and discussed in detail. Further, effects of nanoparticle volume fraction, squeezing parameter, suction/injection parameter and heat source/sink parameter on skin friction and local Nusselt number profiles for different nanoparticles are presented in tables and analyzed.

Findings

Squeezing effect enhances the temperature field and consequently reduces the heat transfer rate. Large values of mixed convection parameter showed a significant effect on velocity components. Also, in many heat transfer applications, nanofluids are potentially useful because of their novel properties. They exhibit high-thermal conductivity compared to the base fluids. Further, squeezing and rotation effects are desirable in control the heat transfer.

Originality/value

Three-dimensional mixed convection flows over in rotating vertical channel filled with nanofluid are very rare in the literature. Mixed convection squeezing three-dimensional flow in a rotating channel filled with nanofluid is first time investigated.

Details

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

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Article
Publication date: 12 October 2018

Tasawar Hayat, Tayyaba Ayub, Taseer Muhammad, Ahmed Alsaedi and M. Mustafa

The purpose of this paper is to construct mathematical model for squeezed flow of carbon-water nanofluid between parallel disks considering Darcy–Forchheimer porous…

Abstract

Purpose

The purpose of this paper is to construct mathematical model for squeezed flow of carbon-water nanofluid between parallel disks considering Darcy–Forchheimer porous medium. Thermal conductivity of carbon nanotubes is estimated through the well-known Xue model. Such research work is not carried out in the past even in the absence of Darcy–Forchheimer porous space. Forchheimer equation is preferred here to account for both low and high velocity inertial effects. Researchers also found that dispersion of carbon nanotubes in water elevates the thermal conductivity of resulting nanofluid by 100 per cent.

Design/methodology/approach

Homotopy analysis method (HAM) is used for the convergent series solutions of the governing system.

Findings

Nusselt number at the lower disk increases when squeezing parameter Sq enlarges. This illustrates that heat transfer rate at the lower wall can be enhanced by increasing the squeezing velocity of the lower disk. The results demonstrate a decreasing trend in temperature profile for increasing volume fraction of carbon nanotubes. Moreover, improvement in heat transfer rate because of existence of carbon nanotubes is also apparent. A significant enhancement in temperature profile is depicted when inertial permeability coefficient is enhanced. Skin friction coefficients at the lower and upper disks are higher for MWCNTs in comparison to the SWCNTs.

Originality/value

To the best of author’s knowledge, no such consideration has been given in the literature yet.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 28 no. 12
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 3 July 2017

M. Sheikholeslami and D.D. Ganji

Nanofluid flow which is squeezed between parallel plates is studied using differential transformation method (DTM). The fluid in the enclosure is water containing…

Abstract

Purpose

Nanofluid flow which is squeezed between parallel plates is studied using differential transformation method (DTM). The fluid in the enclosure is water containing different types of nanoparticles: Al2O3 and CuO. The effective thermal conductivity and viscosity of nanofluid are calculated by Koo–Kleinstreuer–Li (KKL) correlation. The comparison between the results from DTM and numerical method are in well agreement which proofs the capability of this method for solving such problems. Effects of the squeeze number and nanofluid volume fraction on flow and heat transfer are examined. Results indicate that Nusselt number augment with increase of the nanoparticle volume fraction. Also, it can be found that heat transfer enhancement of CuO is higher than Al2O3.

Design/methodology/approach

The problem of nanofluid flow which is squeezed between parallel plates is investigated analytically using DTM. The fluid in the enclosure is water containing different types of nanoparticles: Al2O3 and CuO. The effective thermal conductivity and viscosity of nanofluid are calculated by KKL correlation. In this model, effect of Brownian motion on the effective thermal conductivity is considered. The comparison between the results from DTM and numerical method are in well agreement which proves the capability of this method for solving such problems. The effect of the squeeze number and the nanofluid volume fraction on flow and heat transfer is investigated. The results show that Nusselt number increase with increase of the nanoparticle volume fraction. Also, it can be found that heat transfer enhancement of CuO is higher than Al2O3.

Findings

The effect of the squeeze number and the nanofluid volume fraction on flow and heat transfer is investigated. The results show that Nusselt number increase with increase of the nanoparticle volume fraction. Also, it can be found that heat transfer enhancement of CuO is higher than Al2O3.

Originality/value

This paper is original.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 27 no. 7
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 2 February 2021

V.W.J. Anand, S. Ganesh and Seripah Awang Kechil

The purpose of this study to analyze the unsteady magneto hydrodynamic incompressible viscous fluid flow along the porous parallel plates in which constant periodic…

Abstract

Purpose

The purpose of this study to analyze the unsteady magneto hydrodynamic incompressible viscous fluid flow along the porous parallel plates in which constant periodic suction/injection takes place at lower and upper plate, respectively. By the proper choice of stream function, they obtained exact solution analytically. Velocity components are obtained from exact solution.

Design/methodology/approach

Emissions of the pollutants from the aviation sectors are doubled compared to 2000. There are many recent developments that are actively developed to combat the emission by increasing the performance of the Jet engines. The role of the computational fluid dynamics and the numerical approaches are crucial in terms of research and development.

Findings

Velocity profiles like axial and radial have been drawn for various values of M, D, α and θ. The exact solutions have been solved by differential transformation method. The closed form analytical solutions are obtained for the stream function, axial and radial velocities and flow velocity.

Originality/value

The effects of Darcy parameter, magnetic parameter, Suction Reynolds number and frequency parameter on lower and upper plates are discussed through graphs.

Details

Aircraft Engineering and Aerospace Technology, vol. 93 no. 3
Type: Research Article
ISSN: 1748-8842

Keywords

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Article
Publication date: 28 April 2020

Umair Rashid and Haiyi Liang

In this article, we consider the magnetohydrodynamic (MHD) nanofluid flow over a rotating stretchable disk through porous medium. For porous medium, Darcy’s relation is…

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Abstract

Purpose

In this article, we consider the magnetohydrodynamic (MHD) nanofluid flow over a rotating stretchable disk through porous medium. For porous medium, Darcy’s relation is used. It also encompassed the impact of nanoparticles shape on MHD nanofluid flow and heat transfer. The effect of thermal radiation and Joule heating is also being considered.

Design/methodology/approach

Three categories of nanoparticles are taken into deliberation, i.e. copper, silver and titanium oxide. The nanofluid is made of pure water and various types of sphere- and lamina-shaped nanoparticles. By using appropriate similarity transformation, the governing partial differential equations are transformed to ordinary one. The coupled ordinary differential equations system is tackled numerically by bvp4c method.

Findings

The impact of various pertinent parameters, i.e. solid volume fraction, Hartman number, thermal radiations parameter, Reynolds number, Eckert number, porosity parameter and ratio parameter, on flow and Nusselt number with a fixed value of Prandtl number at 6.2 is discussed in details. The obtained results are presented in the concluding section. The lamina shape of nanoparticles in silver-water performed an excellent role on temperature distribution. The heat transfer rate of lamina shape in copper-water was found to be greater in the system of flow regime.

Originality/value

The authors have discussed the shape effect of nanoparticles on MHD nanofluid flow over a rotating stretchable disk through porous medium using three categories of nanoparticles, such as copper, silver and titanium oxide. To the best of the authors’ knowledge, this is the first study on mass and heat transfer nanofluid flow and no such study is yet published in literature. A detailed mathematical analysis has also to be carried out to prove the regularity of model. The authors believe that the numerical results are original and have not been copied from any other sources.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 12
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 11 January 2021

Mostafa Esmaeili, Hamed Hashemi Mehne and D.D. Ganji

This study aims to explore the idea of solving the problem of squeezing nanofluid flow between two parallel plates using a novel mathematical method.

Abstract

Purpose

This study aims to explore the idea of solving the problem of squeezing nanofluid flow between two parallel plates using a novel mathematical method.

Design/methodology/approach

The unsteady squeezing flow is a coupled fourth-order boundary value problem with flow velocity and temperature as the desired unknowns. In the first step, the conditions that guarantee the existence of a unique solution are obtained. Then following Green’s function-based approach, an iterative method for solving the problem is developed.

Findings

The accuracy of the method is examined by comparing the obtained results with existing numerical data, indicating excellent agreement between the two. In addition, the effects of nanoparticle shape and volume fraction on the flow and heat transfer characteristics are addressed. The results reveal that although the nanoparticle shape strongly affects the temperature distribution in the squeezing flow, it only has a slight impact on the velocity field. Furthermore, the highest and lowest Nusselt numbers belong to the platelets and spherical nanoparticles, respectively.

Originality/value

A semi-analytical method with computational support is developed for solving the unsteady squeezing flow problem. Moreover, the existence and uniqueness of the solution are discussed for the first time.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 31 no. 9
Type: Research Article
ISSN: 0961-5539

Keywords

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Article
Publication date: 25 July 2019

Seyedmohammad Mousavisani, Javad Khalesi, Hossein Golbaharan, Mohammad Sepehr and D.D. Ganji

The purpose of this paper is to find the approximate solutions of unsteady squeezing nanofluid flow and heat transfer between two parallel plates in the presence of…

Abstract

Purpose

The purpose of this paper is to find the approximate solutions of unsteady squeezing nanofluid flow and heat transfer between two parallel plates in the presence of variable heat source, viscous dissipation and inclined magnetic field using collocation method (CM).

Design/methodology/approach

The partial governing equations are reduced to nonlinear ordinary differential equations by using appropriate transformations and then are solved analytically by using the CM.

Findings

It is observed that the enhancing values of aligned angle of the magnetic causes a reduction in temperature distribution. It is also seen that the effect of nanoparticle volume fraction is significant on the temperature but negligible on the velocity profile.

Originality/value

To the best of the authors’ knowledge, no research has been carried out considering the combined effects of inclined Lorentz forces and variable heat source on squeezing flow and heat transfer of nanofluid between the infinite parallel plates.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 5
Type: Research Article
ISSN: 0961-5539

Keywords

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Article
Publication date: 8 March 2011

Ahmet Refik Bahadir and Teymuraz Abbasov

The paper aims to investigate the effect of the electromagnetic field on the convective events which occur when electrically conducting fluid is squeezed between two…

Abstract

Purpose

The paper aims to investigate the effect of the electromagnetic field on the convective events which occur when electrically conducting fluid is squeezed between two parallel disks.

Design/methodology/approach

The effects of the current occurring due to the direct voltage power supply at the thin electrical conducting fluid layer squeezed between the parallel disks, the magnetic field inducted by this current, and Ohmic heating on the squeezing process and heat convection are considered. Both approximate analytical and numerical solutions of the problem are obtained and a good agreement is observed between them.

Findings

The effects of the basic parameters such as Hartmann number, Reynolds number, the ratio of the distance between the disks to the radius of the disks, Prandtl number, Eckert number, heat conduction, and electric current on the squeezing event, and load capacity of the fluid between two parallel disks are able to be determined from the solutions. These solutions also enable the effects of the basic parameters such as Hartmann number, Reynolds number, the ratio of the distance between the disks to the radius of the disks, Prandtl number, Eckert number, heat conduction, and electric current on the squeezing event and load capacity of the fluid between two parallel disks to be determined.

Originality/value

Some important results and comparisons are presented graphically.

Details

Industrial Lubrication and Tribology, vol. 63 no. 2
Type: Research Article
ISSN: 0036-8792

Keywords

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Article
Publication date: 27 August 2019

Muhammad Ijaz Khan, Ahmed Alsaedi, Salman Ahmad and Tasawar Hayat

This paper aims to examine squeezing flow of hybrid nanofluid inside the two parallel rotating sheets. The upper sheet squeezes downward, whereas the lower sheet…

Abstract

Purpose

This paper aims to examine squeezing flow of hybrid nanofluid inside the two parallel rotating sheets. The upper sheet squeezes downward, whereas the lower sheet stretches. Darcy’s relation describes porous space. Hybrid nanofluid consists of copper (Cu) and titanium oxide (TiO2) nanoparticles and water (H2O). Viscous dissipation and thermal radiation in modeling are entertained. Entropy generation analysis is examined.

Design/methodology/approach

Transformation procedure is implemented for conversion of partial differential systems into an ordinary one. The shooting scheme computes numerical solution.

Findings

Velocity, temperature, Bejan number, entropy generation rate, skin friction and Nusselt number are discussed. Key results are mentioned. Velocity field increases vs higher estimations of squeezing parameter, while it declines via larger porosity variable. Temperature of liquid particles enhances vs larger Eckert number. It is also examined that temperature field dominates for TiO2-H2O, Cu-H2O and Cu-TiO2-H2O. Magnitude of heat transfer rate and skin friction coefficient increase against higher squeezing parameter, radiative parameter, porosity variable and suction parameter.

Originality/value

The originality of this paper is investigation of three-dimensional time-dependent squeezing flow of hybrid nanomaterial between two parallel sheets. To the best of the authors’ knowledge, no such consideration has been carried out in the literature.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 29 no. 9
Type: Research Article
ISSN: 0961-5539

Keywords

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Article
Publication date: 13 September 2021

Taimoor Salahuddin, Ali Haider and Metib Alghamdi

The current investigation is communicated to analyze the characteristics of squeezed second grade nanofluid flow enclosed by infinite channel in the existence of both heat…

Abstract

Purpose

The current investigation is communicated to analyze the characteristics of squeezed second grade nanofluid flow enclosed by infinite channel in the existence of both heat generation and variable viscosity. The leading non-linear energy and momentum PDEs are converted into non-linear ODEs by using suitable analogous approach.

Design/methodology/approach

Then the acquired non-linear problem is numerically calculated by using Bvp4c (built in) technique in MATLAB.

Findings

The influence of certain appropriate physical parameters, namely, squeezed number, fluid parameter, Brownian motion, heat generation, thermophoresis parameter, Prandtl number, Schmidt number and variable viscosity parameter on temperature, velocity and concentration distributions are studied and deliberated in detail. Numerical calculations of Sherwood number, Nusselt number and skin friction for distinct estimations of appearing parameters are analyzed through graphs and tables. It is examined that for large values of squeezing parameter, the velocity profile increases, whereas opposite behavior is noticed for large values of variable viscosity and fluid parameter. Moreover, temperature profile increases for large values of Brownian motion, thermophoresis parameter and squeezed parameter and decreases by increases Prandtl number and heat generation. Moreover, concentration profile increases for large values of Brownian motion parameter and decreases by increases thermophoresis parameter, squeezed parameter and Schmidt number.

Originality/value

No one has ever taken infinite squeezed channel having second grade fluid model with variable viscosity and heat generation.

Details

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

Keywords

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