Analytical solution of MHD micropolar nanofluid flow and forced convection heat transfer with entropy generation analysis past a linearly stretching sheet

2021 ◽  
Author(s):  
Sina Sadighi ◽  
Hossein Afshar ◽  
Mohsen Jabbari ◽  
Hossein Ahmadi danesh ashtiani
Keyword(s):  
Angular Velocity ◽  
Forced Convection ◽  
Entropy Generation ◽  
Stretching Sheet ◽  
Convection Heat ◽  
Local Skin ◽  
Entropy Generation Number ◽  
Temperature Distributions ◽  
Generation Number ◽  
Micropolar Nanofluid

Abstract This perusal attempts to model and interpret the entropy generation analysis and the flow field of 2-D, steady, viscous, incompressible and laminar boundary layer and forced convection heat transport of micropolar ferrofluid past a stretching sheet including suction and normal magnetic field effects. The porous sheet’s velocity and temperature are presumed to change linearly. Exact explicit solutions of the velocity, angular velocity and temperature distributions have been derived. The impacts of physical parameters on the local skin friction coefficient, the local Nusselt number, the entropy generation number further the velocities and temperature distributions are analyzed by tables and graphs. The angular velocity has more value than velocity for the least value of the magnetic and material parameters. The entropy generation number has a direct relation with material parameter and Brinkman either Reynolds numbers. Moreover, an inverse relation with the Prandtl 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.

Effects of Energy Dissipation and Variable Thermal Conductivity on Entropy Generation Rate in Mixed Convection Flow

2018 ◽  
Vol 10 (4) ◽  
Author(s):  
Muhammad Qasim ◽  
Muhammad Idrees Afridi
Keyword(s):  
Thermal Conductivity ◽  
Energy Dissipation ◽  
Mixed Convection ◽  
Entropy Generation ◽  
Variable Thermal Conductivity ◽  
Convection Flow ◽  
Mixed Convection Flow ◽  
Entropy Generation Number ◽  
Similarity Transformations ◽  
Generation Number

Analysis of entropy generation in mixed convection flow over a vertically stretching sheet has been carried out in the presence of variable thermal conductivity and energy dissipation. Governing equations are reduced to self-similar ordinary differential equations via similarity transformations and are solved numerically by applying shooting and fourth-order Runge–Kutta techniques. The expressions for entropy generation number and Bejan number are also obtained by using similarity transformations. The influence of embedding physical parameters on quantities of interest is discussed through graphical illustrations. The results reveal that entropy generation number increases significantly in the vicinity of stretching surface and gradually dies out as one move away from the sheet. Also, the entropy generation number decreases with an increase in temperature difference parameter. Moreover, entropy generation number enhances with an enhancement in the Eckert number, Prandtl number, and variable thermal conductivity parameter.

Thermodynamic optimization of nanofluid flow over a non-isothermal wedge with nonlinear radiation and activation energy

2021 ◽  
Author(s):  
M R Acharya ◽  
P Mishra ◽  
Satyananda Panda
Keyword(s):  
Heat Transfer ◽  
Activation Energy ◽  
Reynolds Number ◽  
Entropy Generation ◽  
Volume Fraction ◽  
Mathematical Formulation ◽  
Bejan Number ◽  
Nanofluid Flow ◽  
Entropy Generation Number ◽  
Generation Number

Abstract This paper analyses the augmentation entropy generation number for a viscous nanofluid flow over a non-isothermal wedge including the effects of non-linear radiation and activation energy. We discuss the influence of thermodynamically important parameters during the study, namely, the Bejan number, entropy generation number, and the augmentation entropy generation number. The mathematical formulation for thermal conductivity and viscosity of nanofluid for Al2O3 − EG mixture has been considered. The results were numerically computed using implicit Keller-Box method and depicted graphically. The important result is the change in augmentation entropy generation number with Reynolds number. We observed that adding nanoparticles (volume fraction) tend to enhance augmentation entropy generation number for Al2O3 − EG nanofluid. Further, the investigation on the thermodynamic performance of non-isothermal nanofluid flow over a wedge reveals that adding nanoparticles to the base fluid is effective only when the contribution of heat transfer irreversibility is more than fluid friction irreversibility. This work also discusses the physical interpretation of heat transfer irreversibility and pressure drop irreversibility. This dependency includes Reynolds number and volume fraction parameter. Other than these, the research looked at a variety of physical characteristics associated with the flow of fluid, heat and mass transfer.

Second law analysis of magneto-natural convection in a nanofluid filled wavy-hexagonal porous enclosure

2020 ◽  
Vol 30 (11) ◽  
pp. 4811-4836 ◽  
Author(s):  
Seyyed Masoud Seyyedi ◽  
A.S. Dogonchi ◽  
M. Hashemi-Tilehnoee ◽  
D.D. Ganji ◽  
Ali J. Chamkha
Keyword(s):  
Heat Transfer ◽  
Natural Convection ◽  
Entropy Generation ◽  
Average Nusselt Number ◽  
Convection Heat Transfer ◽  
Natural Convection Heat Transfer ◽  
Content Type ◽  
Entropy Generation Number ◽  
Maximum Value ◽  
Generation Number

Purpose Natural convection heat transfer analysis can be completed using entropy generation analysis. This study aims to accomplish both the natural convection heat transfer and entropy generation analyses for a hexagonal cavity loaded with Cu-H2O nanoliquid subjected to an oriented magnetic field. Design/methodology/approach Control volume-based finite element method is applied to solve the non-dimensional forms of governing equations and then, the entropy generation number is computed. Findings The results portray that both the average Nusselt and entropy generation numbers boost with increasing aspect ratio for each value of the undulation number, while both of them decrease with increasing the undulation number for each amplitude parameter. There is a maximum value for the entropy generation number at a specified value of Hartmann number. Also, there is a minimum value for the entropy generation number at a specified value of angle of the magnetic field. When the volume fraction of nanoparticles grows, the average Nusselt number increases and the entropy generation number declines. The entropy generation number attains to a maximum value at Ha = 14 for each value of aspect ratio. The average Nusselt number ascends 2.9 per cent and entropy generation number decreases 1.3 per cent for Ha = 0 when ϕ increases from 0 to 4 per cent. Originality/value A hexagonal enclosure (complex geometry), which has many industrial applications, is chosen in this study. Not only the characteristics of heat transfer are investigated but also entropy generation analysis is performed in this study. The ecological coefficient of performance for enclosures is calculated, too.

scholarly journals Unsteady electromagnetic radiative nanofluid stagnation-point flow from a stretching sheet with chemically reactive nanoparticles, Stefan blowing effect and entropy generation

2018 ◽  
Vol 232 (2-3) ◽  
pp. 69-82 ◽  
Author(s):  
Puneet Rana ◽  
Nisha Shukla ◽  
O Anwar Bég ◽  
A Kadir ◽  
Bani Singh
Keyword(s):  
Magnetic Field ◽  
Stagnation Point ◽  
Entropy Generation ◽  
Stretching Sheet ◽  
Nonlinear Partial Differential Equations ◽  
Stagnation Point Flow ◽  
Dimensional System ◽  
Electrical Field ◽  
Electric Parameter ◽  
Entropy Generation Number

This article investigates the combined influence of nonlinear radiation, Stefan blowing and chemical reactions on unsteady electro-magneto-hydrodynamic stagnation-point flow of a nanofluid from a horizontal stretching sheet. Both electrical and magnetic body forces are considered. In addition, the effects of velocity slip, thermal slip and mass slip are considered at the boundaries. An analytical method named as homotopy analysis method is applied to solve the non-dimensional system of nonlinear partial differential equations which are obtained by applying similarity transformations on governing equations. The effects of emerging parameters such as Stefan blowing parameter, electric parameter and magnetic parameter on the important physical quantities are presented graphically. In addition, an entropy generation analysis is provided in this article for thermal optimization. The flow is observed to be accelerated both with increasing magnetic field and electrical field. Entropy generation number is markedly enhanced with greater magnetic field, electrical field and Reynolds number, whereas it is reduced with increasing chemical reaction parameter.

scholarly journals Numerical investigation of entropy generation in laminar forced convection flow over inclined backward and forward facing steps in a duct under bleeding condition

2014 ◽  
Vol 18 (2) ◽  
pp. 479-492 ◽  
Author(s):  
Meysam Atashafrooz ◽  
Nassab Gandjalikhan ◽  
Babak Ansari
Keyword(s):  
Numerical Investigation ◽  
Forced Convection ◽  
Entropy Generation ◽  
Fluid Dynamic ◽  
Numerical Results ◽  
Convection Flow ◽  
Bejan Number ◽  
Entropy Generation Number ◽  
Forced Convection Flow ◽  
Laminar Forced Convection

A numerical investigation of entropy generation in laminar forced convection of gas flow over a recess including two inclined backward and forward facing steps in a horizontal duct under bleeding condition is presented. For calculation of entropy generation from the second law of thermodynamics in a forced convection flow, the velocity and temperature distributions are primary needed. For this purpose, the two-dimensional Cartesian coordinate system is used to solve the governing equations which are conservations of mass, momentum and energy. These equations are solved numerically using the computational fluid dynamic techniques to obtain the temperature and velocity fields, while the blocked region method is employed to simulate the inclined surface. Discretized forms of these equations are obtained by the finite volume method and solved using the SIMPLE algorithm. The numerical results are presented graphically and the effects of bleeding coefficient and recess length as the main parameters on the distributions of entropy generation number and Bejan number are investigated. Also, the effect of Reynolds number and bleeding coefficient on total entropy generation which shows the amount of flow irreversibilities is presented for two recess length. The use of present results in the design process of such thermal system would help the system attain the high performance during exploitation. Comparison of numerical results with the available data published in open literature shows a good consistency.

Entropy Generation in Thermally Developing Laminar Forced Convection Through a Slit Microchannel

2010 ◽  
Author(s):  
Arman Sadeghi ◽  
Mostafa Baghani ◽  
Mohammad Hassan Saidi
Keyword(s):  
Forced Convection ◽  
Entropy Generation ◽  
Energy Equation ◽  
Integral Transform ◽  
Axial Coordinate ◽  
Entropy Generation Number ◽  
Group Parameter ◽  
Laminar Forced Convection ◽  
Thermal Entrance ◽  
Increasing Function

The issue of entropy generation in laminar forced convection of a Newtonian fluid through a slit microchannel is analytically investigated by taking the viscous dissipation effect, the slip velocity and the temperature jump at the wall into account. Flow is considered to be hydrodynamically fully developed but thermally developing. The energy equation is solved by means of integral transform. The results demonstrate that to increase Knudsen number is to decrease entropy generation, while the effect of increasing values of Brinkman number and the group parameter is to increase entropy generation. Also it is disclosed that in the thermal entrance region the average entropy generation number over the cross section of channel is an increasing function of axial coordinate.

scholarly journals Thermodynamic analysis of viscoelastic fluid in a porous meduim with prescribed wall heat flux over stretching sheet subjected to a transitive magnetic field

2019 ◽  
Vol 23 (1) ◽  
pp. 219-231 ◽  
Author(s):  
Zineb Chaich ◽  
Salah Saouli ◽  
Issam Rezayguia
Keyword(s):  
Magnetic Field ◽  
Heat Flux ◽  
Entropy Generation ◽  
Stretching Sheet ◽  
Internal Heat ◽  
Wall Heat Flux ◽  
Second Grade ◽  
Entropy Generation Number ◽  
Electrically Conducting ◽  
Layer Flow

An analysis is performed for entropy generation in a steady laminar boundary-layer flow of an electrically conducting second grade fluid in a porous medium prescribed wall heat flux subject to a transverse uniform magnetic field past a semi-infinite stretching sheet, The effects of viscous dissipation, internal heat generation of absorption due to deformation are considered in the energy equation. Kummer?s functions are used to obtain temperature field. The velocity, temperature are used to compute the entropy generation number with a change in various dimensionless parameters.

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