Entropy generation through hexagonal cross-sectional duct for constant wall temperature in laminar flow


Oztop H., Sahin A. Z. , Dagtekin I.

INTERNATIONAL JOURNAL OF ENERGY RESEARCH, vol.28, no.8, pp.725-737, 2004 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 28 Issue: 8
  • Publication Date: 2004
  • Doi Number: 10.1002/er.994
  • Title of Journal : INTERNATIONAL JOURNAL OF ENERGY RESEARCH
  • Page Numbers: pp.725-737
  • Keywords: entropy generation, second law analysis, hexagonal duct, pumping power, laminar flow, HEAT-TRANSFER

Abstract

Second law analysis of heat transfer in laminar flow for hexagonal cross-section duct was analysed analytically. Geometrical effect of hexagonal duct was considered. The variation of total entropy generation was studied along the duct length. As a working fluid water and unused engine oil were used to compare the effect of fluid in the duct. Results were compared with circular cross-section duct. It is found that the non-dimensional entropy generation in a hexagonal cross-section duct can be as high as a factor of four than that for a circular duct. Further, the unused engine oil gives up to about ten times lower non-dimensional entropy generation values than that of water but needs about ten times more pumping power to heat transfer ratio. Copyright (C) 2004 John Wiley Sons, Ltd.