TURBULENCE TRANSITION THRESHOLD OF A BUOYANCY-DRIVEN FLOW OVER AN ISOTHERMAL VERTICAL WALL

Abstract

The integral formalism has been developed in an attempt to predict the mathematical transition threshold from laminar to turbulent regimes in a free convection boundary-layer flow adjacent to an isothermal vertical wall and also to gain a better understanding in the prediction of the turbulence mechanism. The transition threshold is approached herein as the intersection of the two fully developed laminar and turbulent flow regimes. The transition for the isothermal wall condition is Prandtl number dependent and occurs differently depending on whether the dynamical or thermal viewpoints are considered. A change in the transition threshold behavior is observed at Pr = 20.

Keywords

Dates

  • Submission Date2014-03-25
  • Revision Date2014-03-28
  • Acceptance Date2014-05-20
  • Online Date2014-06-15

DOI Reference

10.2298/TSCI140325064P

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