Document Type: Research Paper
Laboratoire Physique et Chimie Th&eacute;oriques (LPCT, UMR CNRS UL 7019), Institut Jean Barriol, Universit&eacute; de Lorraine
Entropy analysis along with convective heat transfer within rotating cylinders of annulus is presented using pure analytical approach for Giesekus rheological model. Two different types of boundary conditions are considered: (a), constant and different temperature at walls, (b) constant heat flux at the outer wall and constant temperature at the inner wall. The derived velocity and temperature profiles are coupled in entropy equation for obtaining the volumetric entropy-generation numbers, the Bejan number expressions. The effects of Deborah number (De), mobility factor ( ), group parameter ( ), Brinkman number (Br) and velocity ratio ( ) on the above parameters are investigated. Results indicate that increment of Brinkman number and group parameters increases irreversibility except when the both cylinders rotate with identical angular speed in the same direction.