The main purpose of this work is to present the use of boundary-domain inte
gral method (BDIM) to analyse the Bow behaviour of non-Newtonian fluids. A
few available parametric viscosity models are applied representing a non-li
near dependence on shear strain rate and shear stress. To evaluate the pres
ented approach the Rayleigh-Benard natural convection was solved at differe
nt Rayleigh number values. (C) 1999 Elsevier Science Ltd. All rights reserv
ed.