Impact of a localized solid cylinder on entropy generation and mixed
convection of nanofluids in a lid-driven trapezoidal cavity
Abstract
The problem of entropy generation and mixed convection in a nanofluid
trapezoidal cavity with an internal solid cylinder is studied
numerically using the finite difference method. The bottom wall is
thermally insulated while the upper wall slides with uniform velocity
from left to right and cooled isothermally. Remainder of these walls are
kept adiabatic. Water-based nanofluids with \Al2O3
nanoparticles are chosen for the investigation. The Boussinesq
approximation is applicable. The influence of Reynolds number,
Richardson number, dimensionless radius of the solid cylinder, location
of the solid cylinder and nanoparticles of volume fraction on
streamlines, isotherms, isentropic as well as the local and average
Nusselt number were investigated. It was found that the location and
size of the solid cylinder are important control parameters for
optimizing heat transfer and Bejan number within the partially heated
trapezoid cavity.