Numerical solution of a singular boundary-value problem in non-Newtonian fluid mechanics

In the present paper we consider the second-order boundary-value problem g " = 1/q (u) over bar g(q), 0 < (u) over bar < 1, (1) with q < 0. We search for a positive solution of (1) which satisfies the bo undary conditions g'(0) = g(1) = 0. This problem arises in the boundary-layer theory for non-Newtonian fluids. In order to obtain numerical solutions, we use two different iterative meth ods and a finite-difference scheme. A variable substitution is used in orde r to improve the approximation and the convergence is accelerated by means of extrapolation methods. Numerical results for different values of q are g iven and compared with the results obtained by other authors. (C) 2000 Else vier Science B.V. All rights reserved.