Abstracts Book - IMRC 2018

• SC2-P004
IRREVERSIBILITY ANALYSIS OF MHD FREE CONVECTIVE COUETTE
FLOW OF A NANOFLUID IN A VERTICAL MICROCHANNEL WITH A
POROUS MEDIUM, CONVECTIVE HEATING AND THERMAL
RADIATION
Guillermo Ibáñez 1 , Aracely López 1 , Joel Pantoja Enríquez 1 , Joel Moreira Acosta 1 , Orlando
Lastres 1
1 Universidad de Ciencias y Artes de Chiapas, Instituto de Investigación e Innovación en
Energías Renovables, Mexico.
Heat transfer and entropy generation in a free convective Couette flow of a
water-based MHD nanofluid containing aluminum oxide in a vertical
microchannel with a porous medium, convective heating and nonlinear thermal
radiation, were investigated. The governing differential equations were reduced
to a set of first order ordinary differential equations and solved numerically with
shooting procedure joined with a fourth order Runge-Kutta integration scheme.
Then, the numerical solutions for the velocity and temperature of nanofluid, as
well as their gradients, were utilized to compute the entropy generation rate.
The effects of the fundamental parameters on the velocity, temperature,
Nusselt number and entropy generation were presented graphically and
analyzed in detail. The results showed that:
1. The nanofluid velocity decreased with both the Hartmann number and
the volume fraction of nanoparticles due to the increment of the Lorentz
force and the friction force, respectively which opposed the movement of
the nanofluid.
2. When the nanoparticle volume fraction increased the nanofluid
temperature decreased down to a certain distance the left plate of
microchannel and then it increased. Here, the increment of the
nanoparticle volume fraction increased the thermal conductivity and
diffusivity of nanofluid and hence heat flux the left portion of
microchannel with higher temperature to the right portion of
microchannel with lower temperature, increased. This produced a
decrement of the temperature in the left region and an increment in the
right region of microchannel.
3. The nanofluid temperature always increased with Hartmann number due
to the increase of Joule dissipation.