IJPAM: Volume 115, No. 2 (2017)

Title

ENTROPY GENERATION RATE IN UNSTEADY
BUOYANCY-DRIVEN HYDROMAGNETIC COUPLE
STRESS FLUID FLOW THROUGH A POROUS CHANNEL

Authors

S.O. Kareem$^1$, S.O. Adesanya$^2$, J.A. Falade$^3$, U.E. Vincent$^4$
$^{1,3,4}$Department of Physical Sciences
Redeemer's University
NIGERIA
$^2$Department of Mathematical Sciences
Redeemer's University
NIGERIA
$^2$Department of Mathematics
Vaal University of Technology
Vanderbijlpark 1911
SOUTH AFRICA
$^4$Department of Physics
Lancaster University
Lancaster LA1 4YB, UNITED KINGDOM

Abstract

In this paper, the entropy generation rate in unsteady buoyancy-driven hydromagnetic couple stress fluid flow through a porous channel has been investigated. The partial differential equations are converted into their corresponding dimensionless equivalence, including the prescribed initial boundary conditions. These equations were solved using the Adomian decomposition method and the behaviour of some pertinent fluid variables, such as velocity, temperature, entropy generation rate and the irreversibility ratio were examined and discussed for different parameters of interest, which include, the Grashof number, the Hartmann's number, the Reynolds number, the Brinkman number and the couple stress parameter. It was found that the entropy generation rate in the fluid model largely depends on the intermolecular forces between the fluid parcels. This has accounted for the observed increase in the entropy generation rate with respect to the couple stress parameter. Other observed entropy generation rate trends found their cause to the internal phenomenon in the fluid, though may be triggered by other forces such as the buoyancy and the Lorentz forces. Graphs are shown to illustrate the findings.

History

Received: January 16, 2017
Revised: May 21, 2017
Published: July 14, 2017

AMS Classification, Key Words

AMS Subject Classification: 76D05, 35Q30
Key Words and Phrases: magnetic field, entropy generation, unsteady flow, irreversibility ratio, buoyancy flow

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How to Cite?

DOI: 10.12732/ijpam.v115i2.9 How to cite this paper?

Source: International Journal of Pure and Applied Mathematics
ISSN printed version: 1311-8080
ISSN on-line version: 1314-3395
Year: 2017
Volume: 115
Issue: 2
Pages: 311 - 326


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