scholarly journals Study of Entropy Generation with Multi-Slip Effects in MHD Unsteady Flow of Viscous Fluid Past an Exponentially Stretching Surface

Symmetry ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 426 ◽  
Author(s):  
Sajjad Haider ◽  
Adnan Saeed Butt ◽  
Yun-Zhang Li ◽  
Syed Muhammad Imran ◽  
Babar Ahmad ◽  
...  
Keyword(s):  
Differential Equations ◽  
Viscous Fluid ◽  
Entropy Generation ◽  
Slip Flow ◽  
Physical Parameters ◽  
Bejan Number ◽  
Entropy Generation Number ◽  
Linear Differential ◽  
Exponentially Stretching ◽  
The Impact

The current study aims to probe the impacts of entropy in a hydromagnetic unsteady slip flow of viscous fluid past an exponentially stretching sheet. Appurtenant similarity variables are employed to transmute the governing partial differential equations into a system of non-linear differential equations, which are analytically solved by utilizing the homotopy analysis method (HAM). Moreover, a shooting technique with fourth–fifth order Runge–Kutta method is deployed to numerically solve the problem. The impact of the physical parameters that influence the flow and heat transmission phenomena are sketched, tabulated and discussed briefly. Additionally, the impact of these parameters on entropy generation is thoroughly discussed by plotting graphs of the local entropy generation number and the Bejan number.

scholarly journals Effects of non-uniform nanoparticle concentration on entropy generation

2021 ◽  
Vol 68 (1 Jan-Feb) ◽  
Author(s):  
Ahmer Mehmood ◽  
Sajid Khan ◽  
Muhammad Usman
Keyword(s):  
Entropy Production ◽  
Entropy Generation ◽  
Working Fluid ◽  
Physical Parameters ◽  
Bejan Number ◽  
Total Entropy ◽  
Entropy Generation Number ◽  
Self Similar Solution ◽  
Nanoparticles Concentration ◽  
The Impact

The entropy generation analysis of a thermal process is capable of determining the efficiency of that process and is therefore helpful to optimize the thermal system operating under various conditions. There are several ingredients upon which the phenomenon of entropy generation can depend, such as the nature of flow and the fluid, the assumed conditions, and the material properties of the working fluid. However, the dependence of entropy generation phenomenon upon such properties has so far not been fully realized, in view of the existing literature. On the other hand, based upon the existing studies, it has been established that the non-uniform concentration of nanoparticles in the base fluid does cause to enhance the heat transfer rate. Therefore, it is logical to investigate the entropy production under the impact of non-homogenous distribution of nanoparticles. Based upon this fact the aim of current study is to explore a comprehensive detail about the influence of non-homogeneous nanoparticles concentration on entropy production phenomenon by considering a laminar viscous flow past a moving continuous flat plate. Non-uniform concentration is considered in the nanofluid modeling in which the Brownian and thermophoretic diffusions are considered which impart significant effects on velocity and temperature profiles. An exact self-similar solution to this problem is observed to be possible and is reported. The effects of various controlling physical parameters such as Brinkman number, Schmidt number, Prandtl number, diffusion parameter, and concentration parameter on both local as well as total entropy generation number and Bejan number are elaborated by several graphs and Tables. The obtained results reveal a significant impact of all aforementioned parameters on entropy generation characteristics. It is observed that by a 20% increase in nanoparticles concentration the total entropy generation is increased up to 67% for a set of fixed values of remaining parameters.

scholarly journals Aspects of Chemical Entropy Generation in Flow of Casson Nanofluid between Radiative Stretching Disks

Entropy ◽  
2020 ◽  
Vol 22 (5) ◽  
pp. 495 ◽  
Author(s):  
Nargis Khan ◽  
Iram Riaz ◽  
Muhammad Sadiq Hashmi ◽  
Saed A. Musmar ◽  
Sami Ullah Khan ◽  
...  
Keyword(s):  
Entropy Generation ◽  
Fluid Velocity ◽  
Axisymmetric Flow ◽  
Casson Fluid ◽  
Physical Parameters ◽  
Bejan Number ◽  
Axial Component ◽  
Radiation Chemical ◽  
Casson Nanofluid ◽  
The Impact

The appropriate utilization of entropy generation may provoke dipping losses in the available energy of nanofluid flow. The effects of chemical entropy generation in axisymmetric flow of Casson nanofluid between radiative stretching disks in the presence of thermal radiation, chemical reaction, and heat absorption/generation features have been mathematically modeled and simulated via interaction of slip boundary conditions. Shooting method has been employed to numerically solve dimensionless form of the governing equations, including expressions referring to entropy generation. The impacts of the physical parameters on fluid velocity components, temperature and concentration profiles, and entropy generation number are presented. Simulation results revealed that axial component of velocity decreases with variation of Casson fluid parameter. A declining variation in Bejan number was noticed with increment of Casson fluid constant. Moreover, a progressive variation in Bejan number resulted due to the impact of Prandtl number and stretching ratio constant.

Physical aspects of magnetized Jeffrey nanomaterial flow with irreversibility analysis

2021 ◽  
Author(s):  
Fazal Haq ◽  
Muhammad Ijaz Khan ◽  
Sami Ullah Khan ◽  
Khadijah M. Abualnaja ◽  
M. A. El-Shorbagy
Keyword(s):  
Differential Equations ◽  
Entropy Generation ◽  
Nonlinear Differential Equations ◽  
Transportation Systems ◽  
Physical Parameters ◽  
Bejan Number ◽  
Convective Boundary ◽  
Homotopy Analysis ◽  
Permeability Parameter ◽  
Thermal Features

Abstract This analysis presents the applications of entropy generation phenomenon in incompressible flow of Jeffrey nanofluid in presence of distinct thermal features. The novel aspects of various features like Joule heating, porous medium, dissipation features and radiative mechanism is addressed. In order to improve the thermal transportation systems based on nanomaterials, the convective boundary conditions are introduced. The thermal viscoelastic nanofluid model is expressed in term of differential equations. The problem is presented via nonlinear differential equations for which analytical expressions are obtained by using homotopy analysis method(HAM). The accuracy of solution is ensured. The effective outcomes of all physical parameters associated with the flow model are carefully examined and underlined through various curves. The observations summarized from current analysis reveal that presence of permeability parameter offers resistance to the flow. A monotonic decrement in local Nusselt number is noted with Hartmann number and Prandtl number. Moreover, entropy generation and Bejan number increases with radiation parameter and fluid parameter.

scholarly journals Entropy Generation on MHD Slip Flow Over a Stretching Cylinder with Heat Generation/Absorption

2018 ◽  
Vol 23 (2) ◽  
pp. 413-428 ◽  
Author(s):  
S. Jain ◽  
S. Bohra
Keyword(s):  
Differential Equations ◽  
Entropy Generation ◽  
Fluid Velocity ◽  
Slip Flow ◽  
Bejan Number ◽  
Stretching Cylinder ◽  
Flow And Heat Transfer ◽  
Permeability Parameter ◽  
Slip Flow Regime ◽  
The Magnetic Field

Abstract In the present study, we have investigated entropy generation on a magnetohydrodynamic fluid flow and heat transfer over a stretching cylinder with a porous medium in slip flow regime. A uniform heat source and radiation is also considered. Similarity transformation has been applied for making an ordinary differential equation from nonlinear governing partial differential equations. The numerical solution for the set of nonlinear ordinary differential equations has been obtained by using the fourth-order Runge-Kutta scheme together with the shooting method. The effects of pertinent parameters such as the magnetic field parameter, permeability parameter, slip parameter, Prandtl number and radiation parameter on the fluid velocity distribution, temperature distribution, entropy generation and Bejan number are discussed graphically.

scholarly journals Entropy Generation in MHD Radiative Flow of CNTs Casson Nanofluid in Rotating Channels with Heat Source/Sink

2019 ◽  
Vol 2019 ◽  
pp. 1-14 ◽  
Author(s):  
Poom Kumam ◽  
Zahir Shah ◽  
Abdullah Dawar ◽  
Haroon Ur Rasheed ◽  
Saeed Islam
Keyword(s):  
Heat Source ◽  
Entropy Generation ◽  
Second Law Of Thermodynamics ◽  
Entropy Generation Rate ◽  
Physical Parameters ◽  
Bejan Number ◽  
Surface Drag ◽  
Casson Nanofluid ◽  
Source Sink ◽  
The Impact

We presented the applications of entropy generation for SWCNTs and MWCNTs based on kerosene oil for Casson nanofluid flow by rotating channels. Kerosene oil has advanced thermal conductivity and exclusive features and has a lot of practical uses due to its unique behavior. That is why we have used kerosene oil as a based fluid. For the entropy generation second law of thermodynamics is applied and implemented for the nanofluid transport mechanism. In the presence of magnetic field, the effects of thermal radiations and heat source/sink on the temperature profiles are studied. The fluid flow is supposed in steady state. With the help of suitable similitude parameters, the leading equations have been transformed to a set of differential equations. The solution of the modeled problem has been carried out with the homotopic approach. The physical properties of carbon nanotubes are shown through tables. The effects of the imbedded physical parameters on the velocities, temperature, entropy generation rate, and Bejan number profiles are investigated and presented through graphs. Moreover, the impact of significant parameters on surface drag force and heat transfer rate is tabulated.

scholarly journals Entropy Generation and Heat Transfer Analysis in MHD Unsteady Rotating Flow for Aqueous Suspensions of Carbon Nanotubes with Nonlinear Thermal Radiation and Viscous Dissipation Effect

Entropy ◽  
2019 ◽  
Vol 21 (5) ◽  
pp. 492 ◽  
Author(s):  
Muhammad Jawad ◽  
Zahir Shah ◽  
Aurungzeb Khan ◽  
Waris Khan ◽  
Poom Kumam ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Carbon Nanotubes ◽  
Differential Equations ◽  
Viscous Dissipation ◽  
Entropy Generation ◽  
Heat Transfer Analysis ◽  
Shrinking Sheet ◽  
Bejan Number ◽  
Nanofluid Flow ◽  
The Impact

The impact of nonlinear thermal radiations rotating with the augmentation of heat transfer flow of time-dependent single-walled carbon nanotubes is investigated. Nanofluid flow is induced by a shrinking sheet within the rotating system. The impact of viscous dissipation is taken into account. Nanofluid flow is assumed to be electrically conducting. Similarity transformations are applied to transform PDEs (partial differential equations) into ODEs (ordinary differential equations). Transformed equations are solved by the homotopy analysis method (HAM). The radiative source term is involved in the energy equation. For entropy generation, the second law of thermodynamics is applied. The Bejan number represents the current investigation of non-dimensional entropy generation due to heat transfer and fluid friction. The results obtained indicate that the thickness of the boundary layer decreases for greater values of the rotation parameter. Moreover, the unsteadiness parameter decreases the temperature profile and increases the velocity field. Skin friction and the Nusselt number are also physically and numerically analyzed.

scholarly journals Entropy Generation on MHD Flow and Heat Transfer of Non-Newtonian Fluid Flow Over a Non-Linear Radially Stretching Sheet

2018 ◽  
Vol 7 (4.10) ◽  
pp. 863
Author(s):  
S. Sreenadh ◽  
V. Ramesh Babu ◽  
G. Gopi Krishna ◽  
S. R.Mishra ◽  
A. N.S.Srinivas
Keyword(s):  
Newtonian Fluid ◽  
Entropy Generation ◽  
Stretching Sheet ◽  
Magnetic Parameter ◽  
Mhd Flow ◽  
Physical Parameters ◽  
Bejan Number ◽  
Entropy Generation Number ◽  
Non Linear ◽  
Flow Phenomena

An investigation is made for analyzing the behavior of MHD flow phenomena of a non-Newtonian fluid over a non-linear radially stretching sheet by using numerical technique. Magnetic field is considered in normal direction to the stretching sheet. With use of similarity transformations, the pdes are transformed into odes. The solution of theses odes are performed by using fourth order Runge - Kutta method along with shooting technique. The significance of different physical parameters characterizes the flow phenomena are analyzed with the use of graphs. The Jeffrey parameter  and magnetic parameter  has significant effect on velocity and temperature distribution over a non-linear stretching sheet. It is noticed that, the higher magnetic parameter results the increase in entropy generation number where the opposite nature is noticed in the case of Bejan number.  

scholarly journals Features of entropy optimization on MHD couple stress nanofluid slip flow with melting heat transfer and nonlinear thermal radiation

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
F. Mabood ◽  
T. A. Yusuf ◽  
Gabriella Bognár
Keyword(s):  
Differential Equations ◽  
Couple Stress ◽  
Slip Flow ◽  
Second Law Of Thermodynamics ◽  
Physical Parameters ◽  
Bejan Number ◽  
Nonlinear Thermal Radiation ◽  
First Order ◽  
Similarity Transformations ◽  
Magnetic Strength

Abstract Numerical analysis is performed for magnetohydrodynamics (MHD) couple stress nanofluid flow over a stretching sheet with melting and nonlinear radiation. The second law of thermodynamics is also incorporated with first-order slip. Nanofluid characteristics for thermophoresis and Brownian moments are encountered. The system that comprises differential equations of partial derivatives is remodeled into the system of differential equations via similarity transformations and then solved numerically through the Runge–Kutta–Fehlberg fourth-fifth (RKF-45) order technique. The physical parameters, which emerges from the derived system are discussed in graphical format. The significant outcomes of the current investigation are that the velocity field decays for a higher magnetic parameter. Another, important outcome of the study is both temperature and concentration are increasing functions of the first-order slip. Nusselt and Sherwood numbers are decreasing with an increase in magnetic strength. Further, Bejan number augment due to enhancement in the first-order slip and couple stress fluid parameters whereas a differing tendency is shown for magnetic and radiation parameters.

Second Law Analysis of Boundary Layer Flow With Variable Fluid Properties

2017 ◽  
Vol 139 (10) ◽  
Author(s):  
M. I. Afridi ◽  
M. Qasim ◽  
O. D. Makinde
Keyword(s):  
Boundary Layer ◽  
Differential Equations ◽  
Entropy Generation ◽  
Boundary Layer Flow ◽  
Numerical Solutions ◽  
Nonlinear Partial Differential Equations ◽  
Entropy Generation Rate ◽  
Bejan Number ◽  
Entropy Generation Number ◽  
Layer Flow

An entropy generation analysis of steady boundary layer flow of viscous fluid with variable properties over an exponentially stretching sheet is presented. The basic nonlinear partial differential equations that govern the flow are reduced to ordinary differential equations by using appropriate transformations. Numerical solutions are obtained by using shooting technique along with Runge–Kutta method. Expressions for the dimensionless volumetric entropy generation rate (NG) and Bejan number are also obtained. The effects of different dimensionless emerging parameters on entropy generation number (NG) and Bejan number (Be) are investigated graphically in detail.

Analysis of Microchannel Heat Sink Performance for Electronics Cooling Based on Thermodynamics

2006 ◽  
Author(s):  
Hessamoddin Abbassi ◽  
Mohammad H. Saidi ◽  
Pouya Zageneh Kazemi
Keyword(s):  
Heat Transfer ◽  
Fluid Flow ◽  
Entropy Generation ◽  
Heat Sink ◽  
Closed Form Solution ◽  
Electronics Cooling ◽  
Bejan Number ◽  
Microchannel Heat Sink ◽  
Entropy Generation Number ◽  
The Impact

Present investigation analyzes the issue of entropy generation in a uniformly heated microchannel heat sink (MCHS). Analytical approach used to solve forced convection problem across MCHS, is porous medium model based on modified Darcy equation for fluid flow and two-equation model for heat transfer between solid and fluid phases. Furthermore, closed form solution of velocity distribution is employed to capture z-direction velocity gradient of flow, which plays a salient role on entropy generation through fluid flow. Analytical expressions for total and thermal entropy generation number (stems from heat transfer), and Bejan number are derived and cast into dimensionless form using velocity and temperature distributions. Besides, entropy generation characteristics in MCHS and the impact of various influential parameters on entropy production have been investigated. Finally, In order to examine the accuracy of analysis, the results of thermal evaluation are compared to one of the previous investigations conducted for thermal optimization of MCHS.

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