scholarly journals Influence of heat generation/absorption and stagnation point on polystyrene–TiO2/H2O hybrid nanofluid flow

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sadaf Masood ◽  
Muhammad Farooq ◽  
Aisha Anjum
Keyword(s):  
Heat Transfer ◽  
Differential Equations ◽  
Stagnation Point ◽  
Entropy Generation ◽  
Heat Generation ◽  
Velocity Ratio ◽  
Hybrid Nanofluid ◽  
Engineering System ◽  
Nanofluid Flow ◽  
Homotopy Analysis

AbstractThis article focuses on hybrid nanofluid flow induced by stretched surface. The present context covers stagnation point flow of a hybrid nanofluid with the effect of heat generation/absorption. Currently most famous class of nanofluids is Hybrid nanofluid. It contains polystyrene and titanium oxide as a nanoparticles and water as a base fluid. First time attributes of heat transfer are evaluated by utilizing polystyrene–TiO2/H2O hybrid nanofluid with heat generation/absorption. Partial differential equations are converted into ordinary differential equation by using appropriate transformations for heat and velocity. Homotopy analysis method is operated for solution of ordinary differential equations. Flow and heat are disclosed graphically for unlike parameters. Resistive force and heat transfer rate is deliberated mathematically and graphically. It is deduced that velocity field enhanced for velocity ratio parameter whereas temperature field grows for heat generation/absorption coefficient. To judge the production of any engineering system entropy generation is also calculated. It is noticed that entropy generation grows for Prandtl number and Eckert number while it shows opposite behavior for temperature difference parameter.

scholarly journals Influence of Heat Generation/Absorption and Stagnation point on Polystyrene -TiO2/H 2 O Hybrid Nanofluid

2021 ◽  
Author(s):  
Sadaf Masood ◽  
Muhammad Farooq
Keyword(s):  
Heat Transfer ◽  
Differential Equations ◽  
Stagnation Point ◽  
Entropy Generation ◽  
Heat Generation ◽  
Velocity Ratio ◽  
Hybrid Nanofluid ◽  
Engineering System ◽  
Homotopy Analysis ◽  
Present Context

Abstract This article focuses on hybrid nanofluid flow induced by stretched surface. The present context covers stagnation point flow of a hybrid nanofluid with the effect of heat gen-eration/absorption. Currently most famous class of nanofluids is Hybrid nanofluid. It contains polystyrene and titanium oxide as a nanoparticles and water as a base fluid. First time attributes of heat transfer are evaluated by utilizing polystyrene-TiO 2 / H 2 O hybrid nanofluid with heat gen-eration/absorption. Partial differential equations are converted into ordinary differential equation by using appropriate transformations for heat and velocity. Homotopy analysis method is operated for solution of ordinary differential equations. Flow and heat are disclosed graphically for unlike parameters. Resistive force and heat transfer rate is deliberated mathematically and graphically. It is deduced that velocity field enhanced for velocity ratio parameter whereas temperature field decays for heat generation/absorption coefficient. To judge the production of any engineering system entropy generation is also calculated. It is noticed that entropy generation grows for Prandtl number and Eckert number while it shows opposite behaviour for temperature difference parameter.

Unsteady MHD Rear Stagnation-Point Flow of a Hybrid Nanofluid with Heat Generation/Absorption Effect

2021 ◽  
Vol 87 (1) ◽  
pp. 41-51
Author(s):  
Nurul Amira Zainal ◽  
Kohilavani Naganthran ◽  
Roslinda Nazar
Keyword(s):  
Heat Transfer ◽  
Differential Equations ◽  
Stagnation Point ◽  
Heat Generation ◽  
Stagnation Point Flow ◽  
Hybrid Nanofluid ◽  
Absorption Effect ◽  
Suction Parameter ◽  
The Impact ◽  
Rear Stagnation Point

The study of unsteady flow is essential in various engineering systems, for instance, the periodic fluid motion and start-up process. Therefore, this numerical study focuses on examining the unsteady magnetohydrodynamics (MHD) rear stagnation-point flow in Al2O3-Cu/H2O hybrid nanofluid past a permeable stretching/shrinking surface with the impact of heat generation/absorption. By choosing a suitable similarity transformation, partial differential equations are transformed into a system of nonlinear ordinary differential equations and solved using the bvp4c function in the MATLAB package. The effects of the solution domain’s operating parameters are analysed, and dual solutions are observable as the sheet shrinks. It is found that the addition of the suction parameter escalates the heat transfer efficiency. Eventually, the existence of the unsteadiness parameter and the heat generation/absorption effect significantly encourage heat transfer deterioration.

Numerical study of melting heat transfer in stagnation-point flow of hybrid nanomaterial (MWCNTs+Ag+kerosene oil)

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Tasawar Hayat ◽  
Khursheed Muhammad ◽  
Ahmed Alsaedi
Keyword(s):  
Heat Transfer ◽  
Differential Equations ◽  
Stagnation Point ◽  
Velocity Ratio ◽  
Hybrid Nanofluid ◽  
Content Type ◽  
Hybrid Nanomaterial ◽  
Volume Fractions ◽  
Curvature Parameter ◽  
Melting Parameter

Purpose The purpose of this study is to analyze hybrid nanofluid (MWCNTs+Ag+Kerosene oil) over a stretched cylinder. Flow analysis is carried out in presence of stagnation-point. Features of heat transport are examined via melting conditions. Design/methodology/approach Governed expression (partial differential equations) for flow and heat transfer are transmitted into ordinary differential equations (ODEs) via applying adequate transformations. For solutions development shooting method (bvp4c) is used on these non-linear coupled ODEs. Findings Comparative observation among hybrid nanofluid (MWCNTs+Ag+Kerosene oil), basefluid (kerosene oil) and nanofluid (MWCNTs+Kerosene oil) are performed. Influences of physical parameters on heat transfer rate, velocity, skinfriction coefficient and temperature are visualized graphically. Higher values nanoparticle volume fractions, curvature parameter, melting parameter and velocity ratio parameter lead to intensification in the velocity profile. The temperature of the fluid reduces with higher values nanoparticle volume fractions, curvature parameter and melting parameter. The surface friction coefficient is minimized via a higher melting parameter and velocity ratio parameter. Heat transmission rate intensifies with velocity ratio parameter, nanoparticle volume friction and curvature parameter while it reduces gradually with larger melting parameter. During comparative study performance of hybrid nanomaterial (MWCNTs+Ag+Kerosene oil) is outstanding and is proceeded by nanomaterial (MWCNTs+ Kerosene oil) and basefluid (kerosene oil). Originality/value In the presented study authors have analyzed the flow of hybrid nanomaterial (MWCNTs+Ag+Kerosene oil) by a stretching cylinder. The further cylinder is subjected to stagnation point and melting condition. The authors believe that all the consequences of the presented study and numerical technique (bvp4c) are original and not published before.

scholarly journals Stability Analysis of Unsteady MHD Rear Stagnation Point Flow of Hybrid Nanofluid

Mathematics ◽  
2021 ◽  
Vol 9 (19) ◽  
pp. 2428
Author(s):  
Nurul Amira Zainal ◽  
Roslinda Nazar ◽  
Kohilavani Naganthran ◽  
Ioan Pop
Keyword(s):  
Heat Transfer ◽  
Stability Analysis ◽  
Differential Equations ◽  
Stagnation Point ◽  
Heat Generation ◽  
Heat Transfer Performance ◽  
Stagnation Point Flow ◽  
Hybrid Nanofluid ◽  
Transfer Performance ◽  
Distribution Profile

Previous studies have reported that investigating the stagnation point flow is relevant in a variety of industrial and technological processes, including extrusion and the polymer industries. Hence, the present work aims to analyse the heat transfer performance of unsteady magnetohydrodynamics (MHD) in hybrid nanofluid and heat generation/absorption impact. The multivariable differential equations with partial derivatives are converted into a specific type of ordinary differential equations by using valid similarity transformations. The resulting mathematical model is clarified utilising the bvp4c function. The results of various control parameters were analysed, and it was discovered that increasing the nanoparticle concentration and magnetic field increases the coefficient of skin friction along the stretching/shrinking surface. The inclusion of the heat generation parameter displays an upward trend in the temperature distribution profile, consequently degrading the heat transfer performance. The findings are confirmed to have more than one solution, and this invariably leads to a stability analysis, which confirms the first solution’s feasibility.

scholarly journals Investigation of binary chemical reaction in magnetohydrodynamic nanofluid flow with double stratification

2021 ◽  
Vol 13 (5) ◽  
pp. 168781402110162
Author(s):  
Aisha Anjum ◽  
Sadaf Masood ◽  
Muhammad Farooq ◽  
Naila Rafiq ◽  
Muhammad Yousaf Malik
Keyword(s):  
Heat Transfer ◽  
Differential Equations ◽  
Hartmann Number ◽  
Concentration Field ◽  
Double Stratification ◽  
Nanofluid Flow ◽  
Homotopy Analysis ◽  
Flow Heat ◽  
Chemically Reactive Species ◽  
Physical Features

This article addresses MHD nanofluid flow induced by stretched surface. Heat transport features are elaborated by implementing double diffusive stratification. Chemically reactive species is implemented in order to explore the properties of nanofluid through Brownian motion and thermophoresis. Activation energy concept is utilized for nano liquid. Further zero mass flux is assumed at the sheet’s surface for better and high accuracy of the out-turn. Trasnformations are used to reconstruct the partial differential equations into ordinary differential equations. Homotopy analysis method is utilized to obtain the solution. Physical features like flow, heat and mass are elaborated through graphs. Thermal stratified parameter reduces the temperature as well as concentration profile. Also decay in concentration field is noticed for larger reaction rate parameter. Both temperature and concentration grows for Thermophoresis parameter. To check the heat transfer rate, graphical exposition of Nusselt number are also discussed and interpret. It is noticed that amount of heat transfer decreases with the increment in Hartmann number. Numerical results shows that drag force increased for enlarged Hartmann number.

scholarly journals Analytical Assessment of (Al2O3–Ag/H2O) Hybrid Nanofluid Influenced by Induced Magnetic Field for Second Law Analysis with Mixed Convection, Viscous Dissipation and Heat Generation

Coatings ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 498
Author(s):  
Wasim Ullah Khan ◽  
Muhammad Awais ◽  
Nabeela Parveen ◽  
Aamir Ali ◽  
Saeed Ehsan Awan ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Viscous Dissipation ◽  
Entropy Generation ◽  
Heat Generation ◽  
Transfer Rate ◽  
Second Law ◽  
Hybrid Nanofluid ◽  
Entropy Generation Number ◽  
Generation Number ◽  
Second Law Analysis

The current study is an attempt to analytically characterize the second law analysis and mixed convective rheology of the (Al2O3–Ag/H2O) hybrid nanofluid flow influenced by magnetic induction effects towards a stretching sheet. Viscous dissipation and internal heat generation effects are encountered in the analysis as well. The mathematical model of partial differential equations is fabricated by employing boundary-layer approximation. The transformed system of nonlinear ordinary differential equations is solved using the homotopy analysis method. The entropy generation number is formulated in terms of fluid friction, heat transfer and Joule heating. The effects of dimensionless parameters on flow variables and entropy generation number are examined using graphs and tables. Further, the convergence of HAM solutions is examined in terms of defined physical quantities up to 20th iterations, and confirmed. It is observed that large λ1 upgrades velocity, entropy generation and heat transfer rate, and drops the temperature. High values of δ enlarge velocity and temperature while reducing heat transport and entropy generation number. Viscous dissipation strongly influences an increase in flow and heat transfer rate caused by a no-slip condition on the sheet.

MHD and nonlinear thermal radiation effects on hybrid nanofluid past a wedge with heat source and entropy generation

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Fazle Mabood ◽  
Anum Shafiq ◽  
Waqar Ahmed Khan ◽  
Irfan Anjum Badruddin
Keyword(s):  
Heat Transfer ◽  
Differential Equations ◽  
Heat Source ◽  
Thermal Radiation ◽  
Entropy Generation ◽  
Entropy Generation Rate ◽  
Design Parameters ◽  
Hybrid Nanofluid ◽  
Nonlinear Thermal Radiation ◽  
Content Type

Purpose This study aims to investigate the irreversibility associated with the Fe3O4–Co/kerosene hybrid-nanofluid past a wedge with nonlinear radiation and heat source. Design/methodology/approach This study reports the numerical analysis of the hybrid nanofluid model under the implications of the heat source and magnetic field over a static and moving wedge with slips. The second law of thermodynamics is applied with nonlinear thermal radiation. The system that comprises differential equations of partial derivatives is remodeled into the system of differential equations via similarity transformations and then solved through the Runge–Kutta–Fehlberg with shooting technique. The physical parameters, which emerges from the derived system, are discussed in graphical formats. Excellent proficiency in the numerical process is analyzed by comparing the results with available literature in limiting scenarios. Findings The significant outcomes of the current investigation are that the velocity field uplifts for higher velocity slip and magnetic strength. Further, the heat transfer rate is reduced with the incremental values of the Eckert number, while it uplifts with thermal slip and radiation parameters. An increase in Brinkmann’s number uplifts the entropy generation rate, while that peters out the Bejan number. The results of this study are of importance involving in the assessment of the effect of some important design parameters on heat transfer and, consequently, on the optimization of industrial processes. Originality/value This study is original work that reports the hybrid nanofluid model of Fe3O4–Co/kerosene.

scholarly journals MHD stagnation-point flow and heat transfer past a stretching/shrinking sheet in a hybrid nanofluid with induced magnetic field

2019 ◽  
Vol 30 (3) ◽  
pp. 1345-1364 ◽  
Author(s):  
Mohamad Mustaqim Junoh ◽  
Fadzilah Md Ali ◽  
Norihan Md Arifin ◽  
Norfifah Bachok ◽  
Ioan Pop
Keyword(s):  
Magnetic Field ◽  
Heat Transfer ◽  
Differential Equations ◽  
Stagnation Point ◽  
Nonlinear Partial Differential Equations ◽  
Stagnation Point Flow ◽  
Shrinking Sheet ◽  
Hybrid Nanofluid ◽  
Induced Magnetic Field ◽  
Content Type

Purpose The purpose of this paper is to investigate the steady magnetohydrodynamics (MHD) boundary layer stagnation-point flow of an incompressible, viscous and electrically conducting fluid past a stretching/shrinking sheet with the effect of induced magnetic field. Design/methodology/approach The governing nonlinear partial differential equations are transformed into a system of nonlinear ordinary differential equations via the similarity transformations before they are solved numerically using the “bvp4c” function in MATLAB. Findings It is found that there exist non-unique solutions, namely, dual solutions for a certain range of the stretching/shrinking parameters. The results from the stability analysis showed that the first solution (upper branch) is stable and valid physically, while the second solution (lower branch) is unstable. Practical implications This problem is important in the heat transfer field such as electronic cooling, engine cooling, generator cooling, welding, nuclear system cooling, lubrication, thermal storage, solar heating, cooling and heating in buildings, biomedical, drug reduction, heat pipe, space aircrafts and ships with better efficiency than that of nanofluids applicability. The results obtained are very useful for researchers to determine which solution is physically stable, whereby, mathematically more than one solution exist. Originality/value The present results are new and original for the problem of MHD stagnation-point flow over a stretching/shrinking sheet in a hybrid nanofluid, with the effect of induced magnetic field.

scholarly journals Unsteady Three-Dimensional MHD Non-Axisymmetric Homann Stagnation Point Flow of a Hybrid Nanofluid with Stability Analysis

Mathematics ◽  
2020 ◽  
Vol 8 (5) ◽  
pp. 784 ◽  
Author(s):  
Nurul Amira Zainal ◽  
Roslinda Nazar ◽  
Kohilavani Naganthran ◽  
Ioan Pop
Keyword(s):  
Heat Transfer ◽  
Mathematical Model ◽  
Stability Analysis ◽  
Differential Equations ◽  
Stagnation Point ◽  
Three Dimensional ◽  
Industrial Sector ◽  
Dual Solutions ◽  
Stagnation Point Flow ◽  
Hybrid Nanofluid

The hybrid nanofluid under the influence of magnetohydrodynamics (MHD) is a new interest in the industrial sector due to its applications, such as in solar water heating and scraped surface heat exchangers. Thus, the present study accentuates the analysis of an unsteady three-dimensional MHD non-axisymmetric Homann stagnation point flow of a hybrid Al2O3-Cu/H2O nanofluid with stability analysis. By employing suitable similarity transformations, the governing mathematical model in the form of the partial differential equations are simplified into a system of ordinary differential equations. The simplified mathematical model is then solved numerically by the Matlab solver bvp4c function. This solving approach was proficient in generating more than one solution when good initial guesses were provided. The numerical results presented significant influences on the rate of heat transfer and fluid flow characteristics of a hybrid nanofluid. The rate of heat transfer and the trend of the skin friction coefficient improve with the increment of the nanoparticles’ concentration and the magnetic parameter; however, they deteriorate when the unsteadiness parameter increases. In contrast, the ratio of the escalation of the ambient fluid strain rate to the plate was able to adjourn the boundary layer separation. The dual solutions (first and second solutions) are obtainable when the surface of the sheet shrunk. A stability analysis is carried out to justify the stability of the dual solutions, and hence the first solution is seen as physically reliable and stable, while the second solution is unstable.

MHD mixed convection stagnation-point flow of a viscoelastic fluid towards a stretching sheet in a porous medium with heat generation and radiation

2015 ◽  
Vol 93 (5) ◽  
pp. 532-541 ◽  
Author(s):  
M. Modather M. Abdou ◽  
E. Roshdy EL-Zahar ◽  
Ali J. Chamkha
Keyword(s):  
Magnetic Field ◽  
Heat Transfer ◽  
Porous Medium ◽  
Differential Equations ◽  
Thermal Radiation ◽  
Stagnation Point ◽  
Viscoelastic Fluid ◽  
Heat Generation ◽  
Stretching Sheet ◽  
Heat Transfer Characteristics

An analysis was carried out to study the effect of thermal radiation on magnetohydrodynamic boundary layer flow and heat transfer characteristics of a non-Newtonian viscoelastic fluid near the stagnation point of a vertical stretching sheet in a porous medium with internal heat generation–absorption. The flow is generated because of linear stretching of the sheet and influenced by the uniform magnetic field that is applied horizontally in the flow region. Using a similarity variable, the governing nonlinear partial differential equations have been transformed into a set of coupled nonlinear ordinary differential equations, which are solved numerically using an accurate implicit finite difference scheme. A comparison of the obtained results with previously published numerical results is done and the results are found to be in good agreement. The effects of the viscoelastic fluid parameter, magnetic field parameter, nonuniform heat source–sink, and the thermal radiation parameter on the heat transfer characteristics are presented graphically and discussed. The values of the skin friction coefficient and the local Nusselt number are tabulated for both cases of assisting and opposing flows.

Sign in / Sign up

Export Citation Format

Share Document