Low Reynolds Number Heat Transfer from a Sphere in a Laminar Flow of Non‐Newtonian Fluids

An approximate solution of a steady‐state problem of heat transfer from a sphere placed in a laminar stream of a non‐Newtonian fluid is obtained for small Reynolds numbers. The problem is solved by the method of matched asymptotic expansions. Expansions for temperature and Nusselt number are obtained. The non‐Newtonian parameters modify the terms of σ2R2 in the expansion for Nusselt number. The results of the present work are for R > 1 in which Prandtl number is of order unity. It has been concluded that the Nusselt number for viscoelastic fluids may increase or decrease depending on their properties. Copyright © 1975 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim