Non-Newtonian flow behaviour in narrow annular gap reactors

In this paper local now investigations under isothermal conditions have bee n established for a narrow annular gap reactor (NAGR, given by a rotor/stat or system with a radius ratio of r(i)/r(o), = 0.8) including two wall scrap er blades of different geometry. Two-dimensional laminar flow fields are co nsidered (with Reynolds numbers below Re < 82.6), based on numerical flow s imulations, where validations with experimental velocity measurements are i n good agreement. Comparisons of the macroscopic flow structuring behaviour are shown for Newtonian and inelastic shear-thinning fluids based on veloc ity profiles, secondary flows, hydrodynamic pressure contours, shear stress and energy dissipation, by varying the rotor velocity (described in terms of a characteristic rotational Reynolds number Re), the scraper blade angle (beta) and the non-Newtonian flow behaviour (power-law exponent n). (C) 20 01 Elsevier Science Ltd. All rights reserved.