EFFECT OF PRANDTL NUMBER ON HEAT TRANSFER CHARACTERISTICS IN AN AXISYMMETRIC SUDDEN EXPANSION: A NUMERICAL STUDY

Abstract

Using the standard k-e turbulence model, an incompressible, axisymmetric turbulent flow with a sudden expansion was simulated. Effect of Prandtl number on heat transfer characteristics downstream of the expansion was investigated. The simulation revealed circulation downstream of the expansion. A secondary circulation (corner eddy) was also predicted. Reat- tachment was predicted at approximately 10 step heights. Corresponding to Prandtl number of 7.0, a peak Nusselt number 13 times the fully-developed value was predicted. The ratio of peak to fully-developed Nusselt number was shown to decrease with decreasing Prandtl number. Location of maximum Nusselt number was insensitive to Prandtl number.

Keywords

Dates

  • Submission Date2007-03-03
  • Revision Date2007-10-16
  • Acceptance Date2007-11-10

DOI Reference

10.2298/TSCI0704171A

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