Nonlinear radiation effects on flow of nanofluid over a porous wedge in the presence of magnetic field

2017 ◽  
Vol 27 (1) ◽  
pp. 48-63 ◽  
Author(s):  
Umar Khan ◽  
Naveed Ahmed ◽  
Bandar Bin-Mohsen ◽  
Syed Tauseef Mohyud-Din
Keyword(s):  
Radiation Effects ◽  
Passive Control ◽  
Skin Friction Coefficient ◽  
Validity Of Results ◽  
Shooting Technique ◽  
Content Type ◽  
Field Radiation ◽  
Moving Wedge ◽  
Runge Kutta ◽  
Clear Description

Purpose The purpose of this paper is to assess the flow of a nanofluid over a porous moving wedge. The passive control model along with the magnetohydrodynamic (MHD) effects is used to formulate the problem. Furthermore, in energy equation, the non-linear thermal radiation has also been incorporated. The equations governing the flow are transformed into a set of ordinary differential equations by using suitable similarity transforms. The reduced system of equations is then solved numerically using a well-known Runge–Kutta–Fehlberg method coupled with a shooting technique. The influence of parameters involved on velocity, temperature and concentration profiles is highlighted with the help of a graphical aid. Expressions for skin-friction coefficient, local Nusselt number and Sherwood number are obtained and presented graphically. Design/methodology/approach Numerical solution of the problem is obtained using the well-known Runge–Kutta–Fehlberg method. Findings The analysis provided gives a clear description that the increase in m and magnetic parameter M results in an increased velocity profile. Both these parameters normalize the velocity field. Radiation parameter, Rd, increases the temperature and concentration of the system so does the temperature ratio θω reduces the heat transfer rate at the wall for both stretching and shrinking wedge. Originality/value In the study presented, the flow of nanofluid over a moving permeable wedge is considered. The solution of the equations governing the flow is presented numerically. For the validity of results obtained, a comparison is also presented with already existing results. To the best of the authors’ knowledge, this investigation is the first of its kind on the said topic.

A BIOCONVECTION MODEL FOR MHD FLOW AND HEAT TRANSFER OVER A POROUS WEDGE CONTAINING BOTH NANOPARTICLES AND GYROTATIC MICROORGANISMS

2016 ◽  
Vol 24 (04) ◽  
pp. 409-429 ◽  
Author(s):  
UMAR KHAN ◽  
NAVEED AHMED ◽  
SYED TAUSEEF MOHYUD-DIN ◽  
BANDAR BIN-MOHSIN
Keyword(s):  
Passive Control ◽  
Mhd Flow ◽  
Skin Friction Coefficient ◽  
Control Model ◽  
Validity Of Results ◽  
Density Profiles ◽  
Gyrotactic Microorganisms ◽  
Shooting Technique ◽  
Flow And Heat Transfer ◽  
Moving Wedge

This paper is dedicated to analyze the flow of a nanofluid over a porous moving wedge in the presence of gyrotactic microorganisms. Magnetohydrodynamic (MHD) effects coupled with the viscous dissipation are taken into consideration. The passive control model is used to formulate the problem. Suitable similarity transforms are employed to transform the equations governing the flow into a set of ordinary differential equations. Solution of the transformed system is obtained numerically using a well-known Runge–Kutta–Fehlberg (RKF) method coupled with shooting technique. Influence of parameters involved on velocity, temperature, concentration and the motile microorganisms density profiles are highlighted using a graphical aid. Expressions for skin friction coefficient, Nusselt number, Sherwood number and the motile microorganisms density number are obtained and presented graphically. For the validity of results obtained, a comparison is also presented with the existing results.

Analysis of radiative magneto nano pseudo-plastic material over three dimensional nonlinear stretched surface with passive control of mass flux and chemically responsive species

2020 ◽  
Vol 16 (5) ◽  
pp. 1061-1083 ◽  
Author(s):  
Muhammad Sohail ◽  
Rabeeah Raza
Keyword(s):  
Radiation Effects ◽  
Passive Control ◽  
Plastic Material ◽  
Fluid Velocity ◽  
Nonlinear Partial Differential Equations ◽  
Three Dimensional ◽  
Numerical Data ◽  
Skin Friction Coefficient ◽  
Normal Velocity ◽  
Content Type

PurposeThe current determination is committed to characterize the boundary layer flow of Williamson nanofluid prompted by nonlinear strained superficial under heat and mass transport mechanisms. Buongiorno model is presented to view the influence of nanoparticles in fluid flow. Scrutiny has been conceded under the action of the transversely smeared magnetic field. Heat and mass relocation exploration are conducted in the companionship of radiation effects and actinic compensation.Design/methodology/approachSimilarity variable is designated to transmute nonlinear partial differential equations of conservation laws of mass, momentum, energy and species into ordinary dimensional expressions. These constitutive and complicated ordinary differential expressions assessing the flow situation are handled efficaciously by manipulating Runge–Kutta–Fehlberg procedure (RK-5) with shooting routine.FindingsThe graphical demonstration is deliberated to scrutinize the variation in velocity, temperature and concentration profiles with respect to flow regulating parameters. Numerical data are displayed through tables in order to surmise variation in skin friction coefficient and Nusselt number. The augmenting values of fluid parameter and magnetic parameter reduces the horizontal fluid velocity, whereas normal velocity upsurges for mounting values of stretching ratio parameter. Moreover, mounting values of radiation parameter and thermophoresis parameter upsurges the temperature profile, whereas, growing values of Prandtl number lessen the temperature field.Practical implicationsThe current exploration is used in many industrial and engineering applications in order to discuss the transport phenomenon.Originality/valueFlow over a nonlinear stretched surface has numerous applications in the industry. The present attempt examines the combined influence of various physical characteristics for the flow of Williamson fluid and no such attempt exist in the available literature.

MHD hybrid nanofluid flow over a permeable stretching/shrinking sheet with thermal radiation effect

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ubaidullah Yashkun ◽  
Khairy Zaimi ◽  
Nor Ashikin Abu Bakar ◽  
Anuar Ishak ◽  
Ioan Pop
Keyword(s):  
Heat Transfer ◽  
Nusselt Number ◽  
Friction Coefficient ◽  
Thermal Radiation ◽  
Radiation Effects ◽  
Skin Friction Coefficient ◽  
Shrinking Sheet ◽  
Hybrid Nanofluid ◽  
Content Type ◽  
Flow And Heat Transfer

Purpose This study aims to investigate the heat transfer characteristic of the magnetohydrodynamic (MHD) hybrid nanofluid over the linear stretching and shrinking surface in the presence of suction and thermal radiation effects. Design/methodology/approach Mathematical equations are transformed into pairs of self-similarity equations using similarity transformation. Boundary value problem solver (bvp4c) in MATLAB was adopted to solve the system of reduced similarity equations. In this study, the authors particularly examine the flow and heat transfer properties for different values of suction and thermal radiation parameters using single-phase nanofluid model. A comparison of the present results shows a good agreement with the published results. Findings It is noticed that the efficiency of heat transfer of hybrid nanofluid (Cu-Al2O3/H2O) is greater than the nanofluid (Cu/H2O). Furthermore, it is also found that dual solutions exist for a specific range of the stretching/shrinking parameter with different values of suction and radiation parameters. The results indicate that the skin friction coefficient and the local Nusselt number increase with suction effect. The values of the skin friction coefficient increases, but the local Nusselt number decreases for the first solution with the increasing of thermal radiation parameter. It is also observed that suction and thermal radiation widen the range of the stretching/shrinking parameter for which the solution exists. Practical implications In practice, the investigation on the flow and heat transfer of MHD hybrid nanofluid through a stretching/shrinking sheet with suction and thermal radiation effects is very important and useful. The problems related to hybrid nanofluid has numerous real-life and industrial applications, for example microfluidics, manufacturing, transportation, military and biomedical, etc. Originality/value In specific, this study focused on increasing thermal conductivity using a hybrid nanofluid mathematical model. This paper is able to obtain the dual solutions. To the best of author’s knowledge, this study is new and there is no previous published work similar to present study.

scholarly journals MHD and Thermal Radiation Effects of a Nanofluid over a Stretching Sheet using HAM

2019 ◽  
Vol 8 (4) ◽  
pp. 3489-3496
Keyword(s):  
Nusselt Number ◽  
Homotopy Analysis Method ◽  
Radiation Effects ◽  
Stretching Sheet ◽  
Skin Friction Coefficient ◽  
Analysis Method ◽  
Partial Differential ◽  
Shooting Technique ◽  
Linear Partial Differential Equations ◽  
Homotopy Analysis

In the present paper, we made an attempt to identify the governing conditions of heat and flow of a nanofluid over a flat plate using Homotopy analysis method (HAM). The arrangement of coupled nonlinear differential (CND) conditions is obtained from the partial differential conditions which will be determined by the homotopy analysis method (HAM). These methods will be useful to draw the conclusion based on the numerical and Graphical results of various parameters such as speed (velocity), concentration and temperature for different values of developing parameters shown in figures. Variations of skin-friction coefficient, Sherwood number and local Nusselt number have shown alongside. Finally conclusions have been drawn based on both diagrams and numerical results, it indicates that the non-linear partial differential equations are changed into a system of CN ODE’s and solved mathematically by using HAM method with shooting technique.

Analysis of Hiemenz flow of Reiner-Rivlin fluid over a stretching/shrinking sheet

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Golam Mortuja Sarkar ◽  
Suman Sarkar ◽  
Bikash Sahoo
Keyword(s):  
Nusselt Number ◽  
Stability Analysis ◽  
Friction Coefficient ◽  
Skin Friction Coefficient ◽  
Dual Solutions ◽  
Shrinking Sheet ◽  
Content Type ◽  
Hiemenz Flow ◽  
Self Similar ◽  
The Stability

Purpose This paper aims to theoretically and numerically investigate the steady two-dimensional (2D) Hiemenz flow with heat transfer of Reiner-Rivlin fluid over a linearly stretching/shrinking sheet. Design/methodology/approach The Navier–Stokes equations are transformed into self-similar equations using appropriate similarity transformations and then solved numerically by using shooting technique. A simple but effective mathematical analysis has been used to prove the existence of a solution for stretching case (λ> 0). Moreover, an attempt has been laid to carry the asymptotic solution behavior for large stretching. The obtained asymptotic solutions are compared with direct numerical solutions, and the comparison is quite remarkable. Findings It is observed that the self-similar equations exhibit dual solutions within the range [λc, −1] of shrinking parameter λ, where λc is the turning point from where the dual solutions bifurcate. Unique solution is found for all stretching case (λ > 0). It is noticed that the effects of cross-viscous parameter L and shrinking parameter λ on velocity and thermal fields show opposite character in the dual solution branches. Thus, a linear temporal stability analysis is performed to determine the basic feasible solution. The stability analysis is based on the sign of the smallest eigenvalue, where positive or negative sign leading to a stable or unstable solution. The stability analysis reveals that the first solution is stable that describes the main flow. Increase in cross-viscous parameter L resulting in a significant increment in skin friction coefficient, local Nusselt number and dual solutions domain. Originality/value This work’s originality is to examine the combined effects of cross-viscous parameter and stretching/shrinking parameter on skin friction coefficient, local Nusselt number, velocity and temperature profiles of Hiemenz flow over a stretching/shrinking sheet. Although many studies on viscous fluid and nanofluid have been investigated in this field, there are still limited discoveries on non-Newtonian fluids. The obtained results can be used as a benchmark for future studies of higher-grade non-Newtonian flows with several physical aspects. All the generated results are claimed to be novel and have not been published elsewhere.

Effect of non-uniform heat source/sink on MHD boundary layer flow and melting heat transfer of Williamson nanofluid in porous medium

2019 ◽  
Vol 15 (2) ◽  
pp. 452-472 ◽  
Author(s):  
Jayarami Reddy Konda ◽  
Madhusudhana Reddy N.P. ◽  
Ramakrishna Konijeti ◽  
Abhishek Dasore
Keyword(s):  
Heat Transfer ◽  
Porous Medium ◽  
Heat Source ◽  
Radiation Effects ◽  
Navier Stokes ◽  
Working Fluid ◽  
Content Type ◽  
Linear Ordinary Differential Equations ◽  
Uniform Heat ◽  
Source Sink

PurposeThe purpose of this paper is to examine the influence of magnetic field on Williamson nanofluid embedded in a porous medium in the presence of non-uniform heat source/sink, chemical reaction and thermal radiation effects.Design/methodology/approachThe governing physical problem is presented using the traditional Navier–Stokes theory. Consequential system of equations is transformed into a set of non-linear ordinary differential equations by means of scaling group of transformation, which are solved using the Runge–Kutta–Fehlberg method.FindingsThe working fluid is examined for several sundry parameters graphically and in a tabular form. It is noticed that with an increase in Eckert number, there is an increase in velocity and temperature along with a decrease in shear stress and heat transfer rate.Originality/valueA good agreement of the present results has been observed by comparing with the existing literature results.

Numerical treatment for Darcy–Forchheimer flow of nanofluid due to a rotating disk with convective heat and mass conditions

2018 ◽  
Vol 28 (11) ◽  
pp. 2531-2550 ◽  
Author(s):  
T. Hayat ◽  
Arsalan Aziz ◽  
Taseer Muhammad ◽  
A. Alsaedi
Keyword(s):  
Biot Number ◽  
Design Methodology ◽  
Rotating Disk ◽  
Random Motion ◽  
Shooting Technique ◽  
Content Type ◽  
Forchheimer Number ◽  
Opposite Trend ◽  
Lower Temperature ◽  
Forchheimer Flow

Purpose The purpose of this study is to examine the Darcy–Forchheimer flow of viscous nanoliquid because of a rotating disk. Thermophoretic diffusion and random motion aspects are retained. Heat and mass transfer features are analyzed through convective conditions. Design/methodology/approach The governing systems are solved numerically by the shooting technique. Findings Higher porosity parameter and Forchheimer number Fr depict similar trend for both velocity profiles f' and g. Both temperature and concentration profiles show increasing behavior for higher Forchheimer number Fr. An increase in Prandtl number Pr corresponds to lower temperature profile, while opposite trend is noticed for thermal Biot number. Larger concentration Biot number exhibits increasing behavior for both concentration and its associated layer thickness. Originality/value To the best of the author’s knowledge, no such consideration has been given in the literature yet.

Exploring the process of workplace bullying in Indian organizations

2017 ◽  
Vol 6 (3) ◽  
pp. 247-273 ◽  
Author(s):  
Arpana Rai ◽  
Upasna A. Agarwal
Keyword(s):  
Grounded Theory ◽  
Workplace Bullying ◽  
Study Data ◽  
Support Network ◽  
Theory Approach ◽  
Validity Of Results ◽  
Content Type ◽  
Hrm Practices ◽  
Bullying Policy ◽  
The Social

Purpose The purpose of this paper is to explore the process of workplace bullying in Indian organizations from the victims’ perspective. Design/methodology/approach The study adopted the grounded theory approach and centered on the participants’ experiences, interpretations, and reactions toward bullying. In total, 23 self-reported victims formed the sample of the study. Data from interviews were analyzed using the coding procedure of grounded theory methodology. To enhance the validity of results, in addition to interviews, member checking technique was also used. Findings The study revealed that the process of workplace bullying in Indian organizations can be broadly explained in four sequential phases: exposure and confusion over mistreatment; making attributions; utilizing options within the organization; and adjustment with the current situation. The findings highlight the importance of sense-making, the social support network, complexity of coping behaviors, silence motives of employees as well as negative and nourishing effects of workplace bullying. The role of culture is visible in the bullying dynamics. Research limitations/implications The study examined bullying from the victims’ perspective; however, perpetrator and bystanders’ perspective would have added interesting insights into the findings. Practical implications The findings point toward the rhetoric of HRM practices in Indian organizations. A well formulated and implemented anti-bullying policy will reduce the rhetoric of HRM practices in Indian organizations. Originality/value The present study contributes to the limited literature on the process of workplace bullying by exploring the process in a new national context (India).

scholarly journals Effects of ohmic heating and viscous dissipation on steady MHD flow near a stagnation point on an isothermal stretching sheet

2009 ◽  
Vol 13 (1) ◽  
pp. 5-12 ◽  
Author(s):  
Pushkar Sharma ◽  
Gurminder Singh
Keyword(s):  
Stagnation Point ◽  
Viscous Dissipation ◽  
Ohmic Heating ◽  
Mhd Flow ◽  
Transverse Magnetic ◽  
Skin Friction Coefficient ◽  
Physical Parameters ◽  
Governing Equations ◽  
Shooting Technique ◽  
Electrically Conducting

Aim of the paper is to investigate effects of ohmic heating and viscous dissipation on steady flow of a viscous incompressible electrically conducting fluid in the presence of uniform transverse magnetic field and variable free stream near a stagnation point on a stretching non-conducting isothermal sheet. The governing equations of continuity, momentum, and energy are transformed into ordinary differential equations and solved numerically using Runge-Kutta fourth order with shooting technique. The velocity and temperature distributions are discussed numerically and presented through graphs. Skin-friction coefficient and the Nusselt number at the sheet are derived, discussed numerically, and their numerical values for various values of physical parameters are compared with earlier results and presented through tables.

scholarly journals Analytical Study of Heat Transfer of a Unsteady Newtonian Nanofluid Flow Problem

2020 ◽  
Vol 15 ◽  
Keyword(s):  
Heat Transfer ◽  
Volume Fraction ◽  
Skin Friction Coefficient ◽  
Parallel Plates ◽  
Nanofluid Flow ◽  
Shooting Technique ◽  
Flow And Heat Transfer ◽  
Transfer Behavior ◽  
Basic Equations ◽  
Squeeze Number

Heat transfer behavior of unsteady flow of squeezing nanofluid (Copper+water) between two parallel plates is investigated. By using the appropriate transformation for the velocity and temperature, the basic equations governing the flow and heat transfer were reduced to a set of ordinary differential equations. These equations subjected to the associated boundary conditions were solved analytically using Homotopy Perturbation Method and numerically using Runge-Kutta-Fehlberg method with shooting technique. Effects on the behavior of velocity and temperature for various values of relevant parameters are illustrated graphically. The skin-friction coefficient, heat transfer and Nusselt number rate are also tabulated for various governing parameters. The results indicate that, for nanofluid flow, the rates of heat transfer and velocity had direct relationship with squeeze number and nanoparticle volume fraction they are also a decreasing function of those parameters

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