Search results

1 – 5 of 5
Per page
102050
Citations:
Loading...
Access Restricted. View access options
Article
Publication date: 1 February 2001

A.A. Mohammadein and Rama Subba Reddy Gorla

A boundary layer analysis is presented to study the heat transfer characteristics of a laminar micropolar fluid boundary layer over a linearly stretching, continuous surface. The…

479

Abstract

A boundary layer analysis is presented to study the heat transfer characteristics of a laminar micropolar fluid boundary layer over a linearly stretching, continuous surface. The study considers the effects of viscous dissipation and internal heat generation. Two cases are studied; namely the surface with prescribed uniform surface temperature (PST‐case) and the surface with prescribed uniform wall heat flux (PHF‐case). The solution for the governing momentum, angular momentum and energy equations are obtained for various values of the material parameters of the micropolar fluid.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 11 no. 1
Type: Research Article
ISSN: 0961-5539

Keywords

Access Restricted. View access options
Article
Publication date: 19 December 2023

Waqar Khan Usafzai, Emad H. Aly and Ioan Pop

This paper aims to study a non-Newtonian micropolar fluid flow over a bidirectional flexible surface for multiple exact solutions of momentum boundary layer and thermal transport…

72

Abstract

Purpose

This paper aims to study a non-Newtonian micropolar fluid flow over a bidirectional flexible surface for multiple exact solutions of momentum boundary layer and thermal transport phenomenon subject to wall mass flux, second-order slip and thermal jump conditions.

Design/methodology/approach

The coupled equations are transformed into ordinary differential equations using similarity variables. Analytical and numerical techniques are used to solve the coupled equations for single, dual or multiple solutions.

Findings

The results show that the stretching flow, shrinking flow, the wall drag, thermal profile and temperature gradient manifest large changes when treated for special effects of the standard parameters. The role of critical numbers is definitive in locating the domains for the existence of exact solutions. The nondimensional parameters, such as mass transfer parameter, bidirectional moving parameter, plate deformation strength parameter, velocity slips, material parameter, thermal jump and Prandtl number, are considered, and their physical effects are presented graphically. The presence of governing parameters exhibits special effects on the flow, microrotation and temperature distributions, and various exact solutions are obtained for the special parametric cases.

Originality/value

The originality and value of this work lie in its exploration of non-Newtonian micropolar fluid flow over a bidirectional flexible surface, highlighting the multiple exact solutions for momentum boundary layers and thermal transport under various physical conditions. The study provides insights into the effects of key parameters on flow and thermal behavior, contributing to the understanding of complex fluid dynamics.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 34 no. 3
Type: Research Article
ISSN: 0961-5539

Keywords

Access Restricted. View access options
Article
Publication date: 27 May 2014

Sahin Ahmed, Abdul Batin and Ali J. Chamkha

The purpose of this paper is to examine the effects of Darcian drag force and radiation-conduction on unsteady two-dimensional magnetohydrodynamic flow of viscous, electrically…

195

Abstract

Purpose

The purpose of this paper is to examine the effects of Darcian drag force and radiation-conduction on unsteady two-dimensional magnetohydrodynamic flow of viscous, electrically conducting and Newtonian fluid over a vertical plate adjacent to a Darcian regime in presence of thermal radiation and transversal magnetic field. A well-tested, numerically stable Crank-Nicolson finite-difference procedure is employed for the conservation equations. Excellent agreement is obtained for numerical solutions with previously published work.

Design/methodology/approach

In this investigation, an efficient, accurate, extensively validated and unconditionally stable finite-difference scheme based on the Crank-Nicolson model is developed to solve the governing coupled, non-linear partial differential equations. The accuracy and effectiveness of the method are demonstrated.

Findings

Different numerical results are obtained and presented graphically to explain the effect of various physical parameters on the velocity and temperature profiles, local, as well as average, skin friction and Nusselt number. It is found that, with a rise in Darcian drag force, flow velocity and temperature are reduced, but increased for all times. Both average and local skin frictions are reduced considerably with an increase in Darcian drag force, but reversed behavior is observed for the local Nusselt number. Increasing the thermal radiation effects accelerated the flow velocity as well as the fluid temperature and wall local skin friction in a saturated porous medium, but effectively reduced the local Nusselt number and average Nusselt number at the wall. Comparison with previously published works in the limits shows excellent agreement.

Research limitations/implications

The analysis is valid for unsteady, two-dimensional laminar flow of an optically thick no-gray gas, electrically conducting, and Newtonian fluid past an isothermal vertical surface adjacent to the Darcian regime with variable surface temperature. An extension to three-dimensional flow case is left for future work.

Practical implications

Practical interest of such study includes applications in electromagnetic lubrication, boundary cooling, bio-physical systems and in many branches of engineering and science. It is well known that the effect of thermal radiation is important in space technology and high temperature processes. Thermal radiation also plays an important role in controlling heat transfer process in polymer processing industry.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 24 no. 5
Type: Research Article
ISSN: 0961-5539

Keywords

Access Restricted. View access options
Article
Publication date: 25 October 2021

Umair Khan, Aurang Zaib, Ioan Pop, Sakhinah Abu Bakar and Anuar Ishak

The boundary-layer analysis is required to reveal the fluid flow behavior in several industrial processes and enhance the products’ effectiveness. Therefore, this research aims to…

98

Abstract

Purpose

The boundary-layer analysis is required to reveal the fluid flow behavior in several industrial processes and enhance the products’ effectiveness. Therefore, this research aims to investigate the buoyancy or mixed convective stagnation-point flow (SPF) and heat transfer of a micropolar fluid filled with hybrid nanoparticles over a vertical plate. The nanoparticles silver (Ag) and titanium dioxide (TiO2) are scattered into various base fluids to form a new-fangled class of (Ag-TiO2/various base fluid) hybrid nanofluid along with different shape factors.

Design/methodology/approach

The self-similarity transformations are used to reformulate the leading requisite partial differential equations into renovated non-linear dimensionless ordinary differential equations. The numerical dual solutions are gained for the transmuted requisite equations with the help of the bvp4c built-in package in MATLAB software. The results are validated by comparing them with previously available published data for a particular case of the present study.

Findings

The impact of various pertaining parameters such as nanoparticle volume fraction, material parameter, shape factor and mixed convective on temperature, heat transfer, fluid motion, micro-rotation and drag force are visualized and scrutinized through tables and graphs. It is observed that dual or non-uniqueness outcomes are found for the case of buoyancy assisting flow, whereas the solution is unique in the buoyancy opposing flow case. Additionally, the fluid motion and micro-rotation profiles decelerate in the presence of nanoparticle volume fraction, while the temperature augments.

Originality/value

The mixed convective stagnation point flow conveying TiO2/Ag hybrid nanofluid with micropolar fluid with various shape factors is the significant originality of the current investigation where multiple outcomes are obtained for the assisting flow. The various base fluids such as glycerin, water and water–ethylene glycol (50%:50%) are considered in the present problem. The bifurcation values of the considered problem do not exist, probably because of various base fluids. To the best of the authors’ knowledge, this work is new and original which were not previously reported.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 32 no. 7
Type: Research Article
ISSN: 0961-5539

Keywords

Access Restricted. View access options
Article
Publication date: 17 December 2019

Himanshu Upreti, Sawan Kumar Rawat and Manoj Kumar

The purpose of this paper is to examine the velocity and temperature profile for a two-dimensional flow of single- and multi-walled nanotubes (CNTs)/H2O nanofluid over a flat…

75

Abstract

Purpose

The purpose of this paper is to examine the velocity and temperature profile for a two-dimensional flow of single- and multi-walled nanotubes (CNTs)/H2O nanofluid over a flat porous plate, under the impact of non-uniform heat sink/source and radiation. The influence of suction/blowing, viscous dissipation and magnetic field is also incorporated.

Design/methodology/approach

The solution of the PDEs describing the flow of nanofluid is accomplished using Runge–Kutta–Fehlberg approach with shooting scheme.

Findings

Quantities of physical importance such as local Nusselt number and skin friction coefficient for both types of nanotubes are computed and shown in tables. Also, the impact of copious factors like Prandtl number, magnetic field, Eckert number, porosity parameter, radiation parameter, non-linear stretching parameter, injection/suction, heating variable, particle volume fraction and non-uniform heat sink/source parameter on temperature and velocity profile is explained in detail with the aid of graphs.

Originality/value

Till date, no study has been reported that examines the role of radiation and non-uniform heat sink/source on MHD flow of CNTs‒water nanofluid over a porous plate. The numerical outcomes attained for the existing work are original and their originality is authenticated by comparing them with earlier published work. This problem is of importance, as there are many applications of the fluid flowing over a flat porous plate.

Details

Multidiscipline Modeling in Materials and Structures, vol. 16 no. 4
Type: Research Article
ISSN: 1573-6105

Keywords

1 – 5 of 5
Per page
102050