Entropy generation due to laminar natural convection over a heated rotating cylinder

Entropy generation due to laminar mixed convection fi-om anisothermal rotat ing cylinder was calculated numerically. The study was conducted for three cylinder radii and covered wide ranges of Reynolds number and buoyancy para meter. Entropy generation increased as the Reynolds number and buoyancy par ameter increased. Entropy generation decreased as the cylinder radius incre ased. For the same combination of Reynolds number and buoyancy parameter, e ntropy generation was mainly due to thermal effects at small cylinder radii and due to viscous effects at large cylinder radii. (C) 1999 Elsevier Scie nce Ltd. All rights reserved.