Mirzazadeh - Department of Chemical Engineering, Amirkabir University of Technology,Tehran, Iran
Rashidi - Department of Chemical Engineering, Amirkabir University of Technology,Tehran, Iran
Hashemabadi - Department of Chemical Engineering, Iran University of Science and Technology, Narmak, Tehran, ۱۶۸۴۴, ran

An analytical solution is derived for the steady state, purely tangential flow of a viscoelastic fluid obeying the simplified Phan-Thien-Tanner (SPTT) constitutive equation in a concentric annulus with inner cylinder rotation. The influence of the Weissenberg number, aspect ratio and an elongational parameter on the velocity profile and fRe are investigated. The results show that fRe decreases with increasing fluid elasticity (eWe2 ) and radius ratio. The results also show that the velocity gradient near rotating cylinder increases when the fluid elasticity increases which indicating shear-thinning behavior of fluid.

SPTT constitutive equation, annular flow, tangential flow