Minimization of Entropy Generation in MHD Mixed Convection Flow with Energy Dissipation and Joule Heating: Utilization of Sparrow-Quack-Boerner Local Non-Similarity Method

2018 ◽  
Vol 387 ◽  
pp. 63-77 ◽  
Author(s):  
M. Idrees Afridi ◽  
Muhammad Qasim ◽  
Najeeb Alam Khan ◽  
Oluwole Daniel Makinde

This article aims to present the non-similar solution of MHD mixed convection flow using the Sparrow-Quack-Boerner local non-similarity method. Entropy analysis is also performed in the presence of energy dissipation and Joule heating. The buoyancy parameter is chosen as the non-similarity variable and the equations are derived up to the second level of truncation. The dependency of dimensionless velocity profile, temperature distribution, Bejan and entropy generation number on physical parameters has been discussed. As far as the knowledge of the authors is concerned, no attempt has been made on the entropy analysis of MHD mixed convection flow by the local non-similarity method.

Author(s):  
Muhammad Qasim ◽  
Muhammad Idrees Afridi

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.


2021 ◽  
Vol 3 (3) ◽  
Author(s):  
Salaika Parvin ◽  
Nepal Chandra Roy ◽  
Rama Subba Reddy Gorla

AbstractIn this study, the ignition characteristics and the flow properties of the mixed convection flow are presented. Detailed formulations of the forced, natural and mixed convection problems have been discussed. In order to avoid inconvenient switch between the forced and natural convection we introduce a continuous transformation in the mixed convection. We make a comparison between these situations which reveal a good agreement. For mixed convection flow, the ignition distance is explicitly expressed as a function of the Prandtl number, reaction parameter and wall temperature. It has been observed that owing to the increase of the aforesaid parameters, the thermal ignition distance is reduced. Numerical results are illustrated for velocity, temperature, and concentration for different physical parameters. Furthermore, the development of combustion is presented by using streamlines, isotherms and isolines of fuel and oxidizer.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Saeed Islam ◽  
Arshad Khan ◽  
Poom Kumam ◽  
Hussam Alrabaiah ◽  
Zahir Shah ◽  
...  

Abstract This work analyses thermal effect for a mixed convection flow of Maxwell nanofluid spinning motion produced by rotating and bidirectional stretching cylinder. Impacts of Joule heating and internal heat source/sink are also taken into account for current investigation. Moreover, the flow is exposed to a uniform magnetic field with convective boundary conditions. The modeled equations are converted to set of ODEs through group of similar variables and are then solved by using semi analytical technique HAM. It is observed in this study that, velocity grows up with enhancing values of Maxwell, mixed convection parameters and reduces with growing values of magnetic parameter. Temperature jumps up with increasing values of heat source, Eckert number, Brownian motion,thermophoresis parameter and jumps down with growing values of Prandtl number and heat sink. The concentration is a growing function of thermophoresis parameter and a reducing function of Brownian motion and Schmidt number.


Entropy ◽  
2016 ◽  
Vol 19 (1) ◽  
pp. 10 ◽  
Author(s):  
Muhammad Afridi ◽  
Muhammad Qasim ◽  
Ilyas Khan ◽  
Sharidan Shafie ◽  
Ali Alshomrani

2013 ◽  
Vol 18 (4) ◽  
pp. 1151-1164 ◽  
Author(s):  
G.V.R. Reddy ◽  
B.A. Reddy ◽  
N.B. Reddy

Abstract The effects of thermal radiation and mass transfer on an unsteady hydromagnetic boundary layer mixed convection flow along a vertical porous stretching surface with heat generation are studied. The fluid is assumed to be viscous and incompressible. The governing partial differential equations are transformed into a system of ordinary differential equations using similarity variables. Numerical solutions of these equations are obtained by using the Runge-Kutta fourth order method along with the shooting technique. Velocity, temperature, concentration, the skin-friction coefficient, Nusselt number and Sherwood number for variations in the governing thermo physical parameters are computed, analyzed and discussed.


2016 ◽  
Vol 139 (3) ◽  
Author(s):  
Palani Sudhagar ◽  
Peri K. Kameswaran ◽  
B. Rushi Kumar

A boundary layer analysis is laid out for the steady, laminar, mixed convection flow past an isothermal vertical cone embedded in a porous medium filled with a nanofluid. The model used for the nanofluid is one which includes the effects of Brownian motion and thermophoresis. A parametric study is performed for different physical parameters, such as magnetic (M), cone angle (m), mixed convection (χ), Brownian motion (Nt), and thermophoresis (Nb), on the velocity, temperature, and nanoparticle concentration profiles. The local Nusselt, Sherwood, and nanoparticle Sherwood number have been laid out in a graphical way. The dependency of the rate of heat and mass transfer on the governing parameters has been discussed.


Sign in / Sign up

Export Citation Format

Share Document