The natural optimality in heat and fluid flow phenomena

Sahin A. Z.

INTERNATIONAL JOURNAL OF EXERGY, vol.9, no.3, pp.346-354, 2011 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 9 Issue: 3
  • Publication Date: 2011
  • Doi Number: 10.1504/ijex.2011.043043
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.346-354
  • Keywords: fluid flow, heat transfer, optimisation, second law analysis, temheat, temheat destruction minimisation
  • Istanbul Technical University Affiliated: Yes


Motivated by the fact that all natural flow processes are similar and governed by common differential equations and that the natural phenomena occur in most sustainable way, the mathematical expression for the common optimum feature of these processes is investigated. Consequently, a new thermodynamic property named 'temheat' is introduced. Based on the second law of thermodynamics and the newly defined property temheat, it is found that a thermodynamic quantity, the rate of total temheat destruction, is minimised for all natural steady flow processes. The temheat destruction minimisation principle is useful in describing the natural flow phenomena and in numerical solution of flow related problems.