Entropy generation of nanofluid flow and heat transfer driven through a paralleled microchannel

2019 ◽  
Vol 97 (6) ◽  
pp. 678-691 ◽  
Author(s):  
Hang Xu ◽  
Ammarah Raees ◽  
Xiao-Hang Xu
Keyword(s):  
Magnetic Field ◽  
Brownian Motion ◽  
Entropy Generation ◽  
Current Model ◽  
Entropy Generation Rate ◽  
Physical Parameters ◽  
Nanofluid Flow ◽  
Buongiorno’S Model ◽  
Flow Models ◽  
Flow And Heat Transfer

In this paper, a fully-developed, immiscible nanofluid flow in a paralleled microchannel in the presence of a magnetic field is investigated. Buongiorno’s model is applied to describe the behaviors of the nanofluid flow. Different from most previous studies on microchannel flow, here the pressure term is considered as unknown, which makes the current model compatible with the commonly accepted channel flow models. The influences of various physical parameters on important physical quantities are given. The entropy generation analysis is performed. Variations of local and global entropy generations with the magnetic field parameter, the electric field, and the viscous dissipation parameter under various ratios of the thermophoresis parameter to the Brownian motion parameter are illustrated. The results indicate that the entropy generation rate strongly depends on the thermophoresis and the Brownian motion parameters. Their increase enhances the total irreversibility of entropy generation.

scholarly journals Shape Effect of Nanosize Particles on Magnetohydrodynamic Nanofluid Flow and Heat Transfer over a Stretching Sheet with Entropy Generation

Entropy ◽  
2020 ◽  
Vol 22 (10) ◽  
pp. 1171
Author(s):  
Umair Rashid ◽  
Dumitru Baleanu ◽  
Azhar Iqbal ◽  
Muhammd Abbas
Keyword(s):  
Heat Transfer ◽  
Entropy Generation ◽  
Stretching Sheet ◽  
Graphical Form ◽  
Physical Parameters ◽  
Shape Effect ◽  
Analysis Method ◽  
Nanofluid Flow ◽  
Flow And Heat Transfer ◽  
Homotopy Analysis

Magnetohydrodynamic nanofluid technologies are emerging in several areas including pharmacology, medicine and lubrication (smart tribology). The present study discusses the heat transfer and entropy generation of magnetohydrodynamic (MHD) Ag-water nanofluid flow over a stretching sheet with the effect of nanoparticles shape. Three different geometries of nanoparticles—sphere, blade and lamina—are considered. The problem is modeled in the form of momentum, energy and entropy equations. The homotopy analysis method (HAM) is used to find the analytical solution of momentum, energy and entropy equations. The variations of velocity profile, temperature profile, Nusselt number and entropy generation with the influences of physical parameters are discussed in graphical form. The results show that the performance of lamina-shaped nanoparticles is better in temperature distribution, heat transfer and enhancement of the entropy generation.

scholarly journals Irreversibility Analysis of Hybrid Nanofluid Flow over a Thin Needle with Effects of Energy Dissipation

Symmetry ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 663 ◽  
Author(s):  
Muhammad Idrees Afridi ◽  
I. Tlili ◽  
Marjan Goodarzi ◽  
M. Osman ◽  
Najeeb Alam Khan
Keyword(s):  
Entropy Generation ◽  
Numerical Solutions ◽  
Free Stream ◽  
Thermal Dissipation ◽  
Heat Transfer Analysis ◽  
Stream Velocity ◽  
Physical Parameters ◽  
Hybrid Nanofluid ◽  
Nanofluid Flow ◽  
Flow And Heat Transfer

The flow and heat transfer analysis in the conventional nanofluid A l 2 O 3 − H 2 O and hybrid nanofluid C u − A l 2 O 3 − H 2 O was carried out in the present study. The present work also focused on the comparative analysis of entropy generation in conventional and hybrid nanofluid flow. The flows of both types of nanofluid were assumed to be over a thin needle in the presence of thermal dissipation. The temperature at the surface of the thin needle and the fluid in the free stream region were supposed to be constant. Modified Maxwell Garnet (MMG) and the Brinkman model were utilized for effective thermal conductivity and dynamic viscosity. The numerical solutions of the self-similar equations were obtained by using the Runge-Kutta Fehlberg scheme (RKFS). The Matlab in-built solver bvp4c was also used to solve the nonlinear dimensionless system of differential equations. The present numerical results were compared to the existing limiting outcomes in the literature and were found to be in excellent agreement. The analysis demonstrated that the rate of entropy generation reduced with the decreasing velocity of the thin needle as compared to the free stream velocity. The hybrid nanofluid flow with less velocity was compared to the regular nanofluid under the same circumstances. Furthermore, the enhancement in the temperature profile of the hybrid nanofluid was high as compared to the regular nanofluid. The influences of relevant physical parameters on flow, temperature distribution, and entropy generation are depicted graphically and discussed herein.

The Overlapping Grid Spectral Collocation Method for Solving Entropy Generation in Casson Nanofluid Flow Past a Stretching Plate

2021 ◽  
Vol 10 (1) ◽  
pp. 45-57
Author(s):  
Zack M. Mburu ◽  
Sabyasachi Mondal ◽  
Precious Sibanda ◽  
Ram Prakash Sharma
Keyword(s):  
Magnetic Field ◽  
Brownian Motion ◽  
Thermal Radiation ◽  
Collocation Method ◽  
Entropy Generation ◽  
Applied Magnetic Field ◽  
Spectral Collocation Method ◽  
Generation Rate ◽  
Entropy Generation Rate ◽  
Spectral Collocation

The current study investigates the intrinsic irreversibility phenomenon of a mixed convection and electrically conducting couple stress Casson fluid motion over a thermally stretching sheet. We have considered the combined effect of applied magnetic field, Brownian motion, thermal radiation, permeability, Casson parameter, and the stretching parameter on the entropy generation rate of the model. The first and second laws of thermodynamics have been applied to examine the flow problem. The obtained dimensionless structure of highly nonlinear ordinary differential equations is then solved numerically applying the overlapping grid spectral collocation method. This method has high accuracy and converges fast. The approximate solutions for velocity, temperature and concentration are used to evaluate the rate of entropy generation and some physical parameters of the flow. For engineering interest, we have obtained tabular results for the skin friction coefficient, Nusselt number, and the Sherwood number for pertinent parameters. We found that entropy generation rate is minimized when there is an increase in the applied magnetic field, thermophoresis parameter, Casson parameter, Brownian motion, and the energy variance parameter. Further, the entropy generation rate is increased by enhancing the stretching parameter, permeability parameter, the Biot number, and thermal radiation parameter.

scholarly journals Entropy generation in Poiseuille flow through a channel partially filled with a porous material

2015 ◽  
Vol 42 (1) ◽  
pp. 35-51 ◽  
Author(s):  
Vikas Kumar ◽  
Shalini Jain ◽  
Kalpna Sharma ◽  
Pooja Sharma
Keyword(s):  
Magnetic Field ◽  
Entropy Generation ◽  
Transverse Magnetic ◽  
Entropy Generation Rate ◽  
Bejan Number ◽  
Clear Fluid ◽  
Entropy Generation Number ◽  
Flow And Heat Transfer ◽  
Permeability Parameter ◽  
Flow Through

In the present paper, a theoretical analysis of entropy generation due to fully developed flow and heat transfer through a parallel plate channel partially filled with a porous medium under the effect of transverse magnetic field and radiation is presented. Both horizontal plates of the channel are kept at constant and equal temperature. An exact solution of governing equation for both porous and clear fluid regions has been obtained in closed form. The entropy generation number and the Bejan number are also calculated. The effects of various parameters such as magnetic field parameter, radiation parameter, Brinkman number, permeability parameter, ratios of viscosities and thermal conductivities are examined on velocity, temperature, entropy generation rate.

scholarly journals Heat transfer and Entropy analysis of airflow around an airfoil subjected to an external magnetic field

2020 ◽  
Author(s):  
Hamed Saffarzadeh ◽  
M.H Djavareshkian
Keyword(s):  
Magnetic Field ◽  
Heat Transfer ◽  
External Magnetic Field ◽  
Entropy Generation ◽  
Generation Rate ◽  
Entropy Generation Rate ◽  
Total Entropy ◽  
Field Source ◽  
Flow And Heat Transfer ◽  
Main Components

Abstract In the present study, the thermal Lattice Boltzmann Technique is combined with the Ghost Fluid method to simulate the flow and heat transfer rate around a NACA 0015 airfoil in the presence of an external magnetic field source. It is tried to investigate the mutual effects of the Hartmann and Reynolds numbers as well as the magnetic field angle and the attack angle of the airfoil on the flow and heat transfer characteristics. Besides, the total entropy generation rate of the system was studied through its main components, i.e. entropy generation rate due to friction, heat transfer, and Magneto Hydrodynamics. Therefore, the tests were carried out for various Re and Ha numbers, plus different magnetic field angles and airfoil attack angles, and their influence on the active parameters which are Cd, Cl, and Nu, along with the entropy generation rate of the system,were recorded. The results revealed that with an increment of the Re number the Cd and Cl graphs drop, but the Nu value raises. Also, the total entropy generation rate of the system is at its maximum around\(\gamma =60\).

Numerical and Statistical Analysis of Dissipative and Heat Absorbing Graphene Maxwell Nanofluid Flow Over a Stretching Sheet

2021 ◽  
Vol 10 (4) ◽  
pp. 600-607
Author(s):  
A. Bhattacharyya ◽  
R. Sharma ◽  
M. K. Mishra ◽  
Ali J. Chamkha ◽  
E. Mamatha
Keyword(s):  
Magnetic Field ◽  
Nusselt Number ◽  
Numerical Solution ◽  
Physical Parameters ◽  
Nonlinear Mathematical Model ◽  
Nanofluid Flow ◽  
Maxwell Nanofluid ◽  
Highly Nonlinear ◽  
Numeric Data ◽  
The Magnetic Field

This paper is basically devoted to carry out an investigation regarding the unsteady flow of dissipative and heat absorbing hydromagnetic graphene Maxwell nanofluid over a linearly stretched sheet taking momentum and thermal slip conditions into account. Ethylene glycol is selected as a base fluid while graphene particles are considered as nanoparticles. The highly nonlinear mathematical model of the problem is converted into a set of nonlinear coupled differential equations by means of fitting similarity variables. Further, Runge-Kutta Fehlberg algorithms along with the shooting scheme are instigated to analyse the numerical solution. The variations in graphene Maxwell nanofluid velocity and temperature owing to different physical parameters have been demonstrated via numerous graphs whereas Nusselt number and skin friction coefficients are illustrated in numeric data form and are reported in different tables. In addition, a statistical method is implemented for multiple quadratic regression estimation analysis on the numerical figures of wall velocity gradient and local Nusselt number to establish the connection among heat transfer rate and physical parameters. Our numerical findings reveal that the magnetic field, unsteadiness, inclination angle of magnetic field and porosity parameters boost the graphene Maxwell nanofluid velocity while Maxwell parameter has a reversal impact on it. The regression analysis confers that Nusselt number is more prone to heat absorption parameter as compared to Eckert number. Finally, the numerical findings are compared with those of earlier published articles under restricted conditions to validate the numerical solution. The comparison of numerical findings shows an excellent conformity among the results.

scholarly journals A Non-Newtonian Magnetohydrodynamics (MHD) Nanofluid Flow and Heat Transfer with Nonlinear Slip and Temperature Jump

Mathematics ◽  
2019 ◽  
Vol 7 (12) ◽  
pp. 1199 ◽  
Author(s):  
Jing Zhu ◽  
Yaxin Xu ◽  
Xiang Han
Keyword(s):  
Heat Transfer ◽  
Nusselt Number ◽  
Temperature Jump ◽  
Thin Sheet ◽  
Velocity Slip ◽  
Skin Friction Coefficient ◽  
Slip Condition ◽  
Physical Parameters ◽  
Nanofluid Flow ◽  
Flow And Heat Transfer

The velocity and thermal slip impacts on the magnetohydrodynamics (MHD) nanofluid flow and heat transfer through a stretched thin sheet are discussed in the paper. The no slip condition is substituted for a new slip condition consisting of higher-order slip and constitutive equation. Similarity transformation and Lie point symmetry are adopted to convert the derived governed equations to ordinary differential equations. An approximate analytical solution is gained through the homotopy analysis method. The impacts of velocity slip, temperature jump, and other physical parameters on flow and heat transfer are illustrated. Results indicate that the first-order slip and nonlinear slip parameters reduce the velocity boundary layer thickness and Nusselt number, whereas the effect on shear stress is converse. The temperature jump parameter causes a rise in the temperature, but a decline in the Nusselt number. With the increase of the order, we can get that the error reaches 10 − 6 from residual error curve. In addition, the velocity contours and the change of skin friction coefficient are computed through Ansys Fluent.

Entropy Generation on Maxwell Fluid Flow Past an Inclined Stretching Plate with Slip and Convective Surface Conditon: Darcy-Forchheimer Model

2019 ◽  
Vol 26 ◽  
pp. 62-83
Author(s):  
Tunde Abdulkadir Yusuf ◽  
Jacob Abiodun Gbadeyan
Keyword(s):  
Porous Medium ◽  
Differential Equations ◽  
Entropy Generation ◽  
Mhd Flow ◽  
Maxwell Fluid ◽  
Entropy Generation Rate ◽  
Physical Parameters ◽  
Convective Boundary ◽  
Linear Ordinary Differential Equations ◽  
Non Linear

In this study the effect of entropy generation on two dimensional magnetohydrodynamic (MHD) flow of a Maxwell fluid over an inclined stretching sheet embedded in a non-Darcian porous medium with velocity slip and convective boundary condition is investigated. Darcy-Forchheimer based model was employed to describe the flow in the porous medium. The non-linear thermal radiation is also taken into account. Similarity transformation is used to convert the non-linear partial differential equations to a system of non-linear ordinary differential equations. The resulting transformed equations are then solved using the Homotopy analysis method (HAM). Influence of various physical parameters on the dimensionless velocity profile, temperature profile and entropy generation are shown graphically and discussed in detail while the effects of these physical parameters on velocity gradient and temperature gradient are aided with the help of Table. Furthermore, comparison of some limiting cases of this model was made with existing results. The results obtained are found to be in good agreement with previously published results. Moreover, increase in local inertial coefficient parameter is found to decrease the entropy generation rate.

scholarly journals Effect of Velocity Slip Boundary Condition on the Flow and Heat Transfer of Cu-Water and TiO2-Water Nanofluids in the Presence of a Magnetic Field

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Abdelhalim Ebaid ◽  
Fahd Al Mutairi ◽  
S. M. Khaled
Keyword(s):  
Magnetic Field ◽  
Heat Transfer ◽  
Fluid Velocity ◽  
Velocity Slip ◽  
Slip Boundary Condition ◽  
Dual Solutions ◽  
Slip Condition ◽  
Shrinking Sheet ◽  
Physical Parameters ◽  
Flow And Heat Transfer

In nanofluid mechanics, it has been proven recently that the no slip condition at the boundary is no longer valid which is the reason that we consider the effect of such slip condition on the flow and heat transfer of two types of nanofluids. The present paper considers the effect of the velocity slip condition on the flow and heat transfer of the Cu-water and the TiO2-water nanofluids over stretching/shrinking sheets in the presence of a magnetic field. The exact expression for the fluid velocity is obtained in terms of the exponential function, while an effective analytical procedure is suggested and successfully applied to obtain the exact temperature in terms of the generalized incomplete gamma function. It is found in this paper that the Cu-water nanofluid is slower than the TiO2-water nanofluid for both cases of the stretching/shrinking sheets. However, the temperature of the Cu-water nanofluid is always higher than the temperature of the TiO2-water nanofluid. In the case of shrinking sheet the dual solutions have been obtained at particular values of the physical parameters. In addition, the effect of various physical parameters on such dual solutions is discussed through the graphs.

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