A perturbation based analysis to investigate forced convection in a porous saturated tube

Fully developed laminar steady forced convection inside a circular tube filled with saturated porous medium and with uniform heat flux at the wall is investigated on the basis of a Brinkman model which is appropriate for hyperporous materials which are of current practical importance. The "WKB method" is applied for small values of the Darcy number. For the case of large Darcy number, the solution for the Brinkman momentum equation is found in terms of an asymptotic expansion. With the velocity distribution determined, the energy equation is solved using the same asymptotic technique. The results for limiting cases were found to be in good agreement with those available in the open literature. (C) 2003 Elsevier B.V. All rights reserved.