Effect of Thermal Radiation on the Entropy Generation of Hydromagnetic Flow Through Porous Channel

In this study, effect of thermal radiation on the entropy generation rate of a hydromagnetic incompressible viscous flow through porous channel has been studied. The governing equations are formulated, non-dimensionalized and solved by Adomian decomposition and Differential Transform methods. The obtained velocity and temperature profiles are used to compute the entropy generation rate and Bejan number. The influence of various flow parameters on the velocity, temperature, entropy generation rate and Bejan number are discussed graphicall

Thermodynamics Analysis of Radiative Hydromagnetic Couple Stress Fluid through a Channel

This work applies second law of thermodynamics to analyse the effect of radiation on electrically conducting couple stress fluid through a channel. A constant magnetic field is introduced across the flow channel and the resulting Navier- Stokes and energy equations are non-dimensionalized and solved using Adomian decomposition method (ADM) and differential transform method (DTM). The obtained velocity and temperature profiles are used to calculate the entropy generation rate and irreversibility ratio. The effects of radiation, magnetic field and couple stress parameters on the velocity, temperature, entropy generation rate and Bejan number are discussed with the aid of graphs. From the study, it is observed that increase in magnetic field and couple stress parameters reduces the fluid velocity while an increase in radiation parameter reduces the temperature of the fluid. Furthermore, radiation parameter increases entropy generation as heat transfer dominates irreversibility

ANALYSIS OF ENTROPY GENERATION DUE TO MAGNETOHYDRODYNAMIC COUPLE STRESS FLUID

We demonstrate the first reconfigurable photonic metamaterial controlled by electrical currents and magnetic fields, providing first practically useful solutions for sub-megahertz and high contrast modulation of metamaterial optical properties

Generation of entropy and forced convection of heat in a conduit partially filled with porous media- Local thermal non-equilibrium and exothermicity effects applied thermal engineering

The performance of a two-dimensional, axisymmetric channel with porous inserts attached to the walls is analyzed from the perspective of the first and second laws of thermodynamics. In this analysis, the flow is assumed to be fully developed with a constant heat flux imposed on the external surfaces of the walls, while heat could be internally generated by the fluid and solid phases. Using a Darcy-Brinkman model of momentum transport along with a two-equation thermal energy model, a convective model was developed to describe the thermal boundary conditions on the porous-fluid interface. The so-called Model A was employed on the walls of the channel and semi-analytical solutions were developed for the hydrodynamic, temperature, entropy generation fields and the Nusselt number, and an extensive parametric study was subsequently, conducted. The results indicated that the inclusion of exothermicity leads to significant modifications in the thermal and entropic behaviour of the system. In particular, through comparison with the recent literature, it was demonstrated that exothermicity can significantly impact the influence of the porous-fluid interface model upon the generation of both the local and total entropy within the system

Entropy Generation Analysis in a Variable Viscosity MHD Channel Flow with Permeable Walls and Convective Heating

This paper examines the effects of the thermodynamic second law on steady flow of an incompressible variable viscosity electrically conducting fluid in a channel with permeable walls and convective surface boundary conditions. The nonlinear model governing equations are solved numerically using shooting quadrature. Numerical results of the velocity and temperature profiles are utilised to compute the entropy generation number and the Bejan number. The results revealed that entropy generation minimization can be achieved by appropriate combination of the regulated values of thermophysical parameters controlling the flow systems

Analytical Solution of a Steady Non-Reacting Laminar Fluid Flow in a Channel Filled With Saturated Porous Media with Two Distinct Horizontal Impermeable Wall Conditions

An analysis of the study of momentum and heat transfer characteristics of a non-reacting Newtonian viscous incompressible laminar fluid flow in a channel filled with saturated porous media with both isothermal and isoflux boundary conditions has been carried out.  The dimensionless non-linear coupled ordinary differential equations governing the flow and the heat transfer characteristics are solved analytically using the method of undetermined coefficients. Details of velocities and temperature fields for various values of the emerging parameters of the steady solutions of the problems are presented using contour graphs. It was shown that the porous medium may be used to control the flow in a saturated porous media using less permeable materials which offer greater resistance to the boundary-layer momentum development. It was further revealed that increase in porous media permeability and decrease in ratio of viscosities, help to enhance the fluid flow; however the input of the viscous term on the flow behaviour is insignificant for extremely lower values of Darcy number. It was also shown that the fluid temperature is more influenced in isothermal and isoflux processes if the Darcy number, Da, or Brinkman number, Br, or both are increased and if the ratio of viscosities M, is decreased. Keywords: laminar flow, porous medium, impermeable walls, isothermal, isoflux

Thermodynamic analysis of a variable viscosity reactive hydromagnetic couette flow within parallel plates

This investigation is to consider the impact of a temperature-dependent variable viscosity of a reactive hydromagnetic Couette fluid flowing within parallel plates. The variable property of the fluid viscosity is thought to be an exponential relation of temperature under the impact of magnetic strength. The differential equations controlling the smooth movement of fluid and energy transfer are modeled and solved by using the series solution of modified Adomian decomposition technique (mADM). The outcomes are shown in tables and graphs for different estimations of thermophysical properties present in the flow regime together with the rate of entropy generation and irreversibility distribution outcome. Keywords: Reactive fluids, Couette Flow, variable viscosity, hydromagnetic and modified Adomian decomposition method (mADM)

MHD flow of non-Newtonian ferro nanofluid between two vertical porous walls with Cattaneo–Christov heat flux, entropy generation, and time-dependent pressure gradient

This article studies the magnetohydrodynamic flow of non-Newtonian ferro nanofluid subject to time-dependent pressure gradient between two vertical permeable walls with Cattaneo–Christov heat flux and entropy generation. In this study, blood is considered as non-Newtonian fluid (couple stress fluid). Nanoparticles’ shape factor, Joule heating, viscous dissipation, and radiative heat impacts are examined. This investigation is crucial in nanodrug delivery, pharmaceutical processes, microelectronics, biomedicines, and dynamics of physiological fluids. The flow governing partial differential equations are transformed into the system of ordinary differential equations by deploying the perturbation process and then handled with Runge–Kutta 4th-order procedure aided by the shooting approach. Hamilton–Crosser model is employed to analyze the thermal conductivity of different shapes of nanoparticles. The obtained results reveal that intensifying Eckert number leads to a higher temperature, while the reverse is true for increased thermal relaxation parameter. Heat transfer rate escalates for increasing thermal radiation. Entropy dwindles for intensifying thermal relaxation parameter