scholarly journals Entropy Generation in MHD Conjugate Flow with Wall Shear Stress over an Infinite Plate: Exact Analysis

Entropy ◽  
2019 ◽  
Vol 21 (4) ◽  
pp. 359 ◽  
Author(s):  
Arshad Khan ◽  
Faizan ul Karim ◽  
Ilyas Khan ◽  
Tawfeeq Alkanhal ◽  
Farhad Ali ◽  
...  
Keyword(s):  
Shear Stress ◽  
Wall Shear Stress ◽  
Entropy Generation ◽  
Infinite Plate ◽  
Mhd Flow ◽  
Bejan Number ◽  
Grashof Number ◽  
Entropy Generation Number ◽  
Mass And Heat Transfer ◽  
Wall Shear

The current work will describe the entropy generation in an unsteady magnetohydrodynamic (MHD) flow with a combined influence of mass and heat transfer through a porous medium. It will consider the flow in the XY plane and the plate with isothermal and ramped wall temperature. The wall shear stress is also considered. The influences of different pertinent parameters on velocity, the Bejan number and on the total entropy generation number are reported graphically. Entropy generation in the fluid is controlled and reduced on the boundary by using wall shear stress. It is observed in this paper that by taking suitable values of pertinent parameters, the energy losses in the system can be minimized. These parameters are the Schmitt number, mass diffusion parameter, Prandtl number, Grashof number, magnetic parameter and modified Grashof number. These results will play an important role in the heat flow of uncertainty and must, therefore, be controlled and managed effectively.

MHD Flow of Cu-Al2O3/Water Hybrid Nanofluid in Porous Channel: Analysis of Entropy Generation

2017 ◽  
Vol 377 ◽  
pp. 42-61 ◽  
Author(s):  
Sanatan Das ◽  
Rabindra Nath Jana ◽  
Oluwole Daniel Makinde
Keyword(s):  
Entropy Generation ◽  
Mhd Flow ◽  
Transverse Magnetic ◽  
Porous Channel ◽  
Hybrid Nanofluid ◽  
Bejan Number ◽  
Governing Equations ◽  
Transfer Enhancement ◽  
Entropy Generation Number ◽  
Channel Analysis

In this investigation, a magnetohydrodynamic (MHD) flow of AlO /water nanofluid and Cu-AlO /water hybrid nanofluid through a porous channel is analyzed in the presence of a transverse magnetic field. An exact solution of the governing equations has been obtained in closed form. The entropy generation number and the Bejan number are also obtained. The influences of each of the governing parameters on velocity, temperature, entropy generation and Bejan number are displayed graphically and the physical aspects are discussed. In addition, a comparison of the heat transfer enhancement level due to the suspension of AlO and Cu nanoparticles in water as regular nanofluids and as hybrid Cu-AlO /water nanofluid is reported.

Second Law Analysis of MHD Squeezing Flow of Casson Fluid Between Two Parallel Disks

2018 ◽  
Vol 16 (6) ◽  
Author(s):  
Odelu Ojjela ◽  
Kesetti Ramesh ◽  
Samir K. Das
Keyword(s):  
Entropy Generation ◽  
Chemical Engineering ◽  
Mhd Flow ◽  
Casson Fluid ◽  
Squeezing Flow ◽  
Bejan Number ◽  
Field Equations ◽  
Linear Ordinary Differential Equations ◽  
Entropy Generation Number ◽  
Parallel Disks

AbstractThe present article deals the entropy generation due to heat and mass transfer of an unsteady MHD flow of a Casson fluid squeezed between two parallel disks. The upper disk is taken to be impermeable and the lower one is porous. The flow field equations are reduced to non-linear ordinary differential equations by using similarity transformations and the resulting ODE problem is solved by shooting technique with Runge-Kutta 4thorder method. The effects of various non dimensional fluid and geometric parameters on the velocity components, temperature, concentration, entropy generation number, Bejan number, skin friction and Nusselt number are illustrated through graphs and tables. It is noticed that the temperature of the fluid is enhanced with Eckert number, whereas the concentration of the fluid decreased with Casson fluid parameter. The present study is applicable to nuclear engineering cooling systems, wire and blade coating, extrusion of polymer fluids, optical fibers, magnetohydrodynamics and optimization of chemical engineering processes.

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 Effects of Wall Shear Stress on MHD Conjugate Flow over an Inclined Plate in a Porous Medium with Ramped Wall Temperature

2014 ◽  
Vol 2014 ◽  
pp. 1-15 ◽  
Author(s):  
Arshad Khan ◽  
Ilyas Khan ◽  
Farhad Ali ◽  
Sharidan Shafie
Keyword(s):  
Porous Medium ◽  
Shear Stress ◽  
Wall Shear Stress ◽  
Exact Solutions ◽  
Wall Temperature ◽  
Mhd Flow ◽  
Inclined Plate ◽  
Constant Wall Temperature ◽  
Laplace Transform Technique ◽  
Wall Shear

This study investigates the effects of an arbitrary wall shear stress on unsteady magnetohydrodynamic (MHD) flow of a Newtonian fluid with conjugate effects of heat and mass transfer. The fluid is considered in a porous medium over an inclined plate with ramped temperature. The influence of thermal radiation in the energy equations is also considered. The coupled partial differential equations governing the flow are solved by using the Laplace transform technique. Exact solutions for velocity and temperature in case of both ramped and constant wall temperature as well as for concentration fields are obtained. It is found that velocity solutions are more general and can produce a huge number of exact solutions correlative to various fluid motions. Graphical results are provided for various embedded flow parameters and discussed in detail.

Local Measurement of Loss Using Heated Thin-Film Sensors

1999 ◽  
Vol 121 (4) ◽  
pp. 814-818 ◽  
Author(s):  
M. R. D. Davies ◽  
F. K. O’Donnell
Keyword(s):  
Thin Film ◽  
Shear Stress ◽  
Wall Shear Stress ◽  
Entropy Generation ◽  
Free Stream ◽  
Unit Area ◽  
Generation Rate ◽  
Entropy Generation Rate ◽  
Thin Film Sensors ◽  
Wall Shear

A calibration equation is derived linking the nondimensional entropy generation rate per unit area with the nondimensional aerodynamic wall shear stress and free-stream pressure gradient. It is proposed that the latter quantities, which can be measured from surface sensors, be used to measure the profile entropy generation rate. It is shown that the equation is accurate for a wide range of well-defined laminar profiles. To measure the dimensional entropy generation rate per unit area requires measurement of the thickness of the boundary layer. A general profile equation is given and used to show the range of accuracy of a further simplification to the calibration. For flows with low free-stream pressure gradients, the entropy generation rate is very simply related to the wall shear stress, if both are expressed without units. An array of heated thin film sensors is calibrated for the measurement of wall shear stress, thus demonstrating the feasibility of using them to measure profile entropy generation rate.

scholarly journals Local Measurement of Loss Using Heated Thin Film Sensors

1998 ◽  
Author(s):  
Mark R. D. Davies ◽  
Francis K. O’Donnell
Keyword(s):  
Thin Film ◽  
Shear Stress ◽  
Wall Shear Stress ◽  
Entropy Generation ◽  
Free Stream ◽  
Unit Area ◽  
Generation Rate ◽  
Entropy Generation Rate ◽  
Thin Film Sensors ◽  
Wall Shear

A calibration equation is derived linking the non-dimensional entropy generation rate per unit area with the non-dimensional aerodynamic wall shear stress and free stream pressure gradient. It is proposed that the latter quantities, which can be measured from surface gauges, be used to measure the profile entropy generation rate. It is shown that the equation is accurate for a wide range of well-defined laminar profiles. To measure the dimensional entropy generation rate per unit area requires measurement of the thickness of the boundary layer. A general profile equation is given and used to show the range of accuracy of a further simplification to the calibration. For flows with low free stream pressure gradients, the entropy generation rate is very simply related to the wall shear stress, if both are expressed without units. An array of heated thin film sensors is calibrated for the measurement of wall shear stress, thus demonstrating the feasibility of using them to measure profile entropy generation rate.

Sign in / Sign up

Export Citation Format

Share Document