Algebraic turbulent heat flux model for prediction of thermal stratification in piping systems

M. Pellegrini, H. Endo, Elia Merzari, H. Ninokata

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

The effect of stratification on the flow in bounded geometries is studied through computational fluid dynamics and two different modelings of the turbulent heat flux: constant turbulent Prandtl number and Algebraic Heat Flux Model (AHFM). The main feature of the work is evaluation of the effect of buoyancy on the thermal quantities, velocity field, and related pressure drop. For evaluation of the turbulent heat flux and temperature field, AHFM has been demonstrated to be superior to the simple eddy diffusivity approach. However, serious concerns remain for the prediction of the velocity field in both isothermal and nonisothermal conditions, since greater uncertainties for the obtained pressure drop and related Fanning friction factor can be introduced. Incremental pressure drop is also investigated in conditions deviating from fully developed flows, in order to study stratification effects qualitatively using an engineering method.

Original languageEnglish (US)
Pages (from-to)144-156
Number of pages13
JournalNuclear Technology
Volume181
Issue number1
DOIs
StatePublished - Jan 1 2013

Fingerprint

Thermal stratification
Piping systems
stratification
Heat flux
heat flux
pressure drop
Pressure drop
predictions
velocity distribution
friction factor
evaluation
Prandtl number
computational fluid dynamics
Buoyancy
buoyancy
diffusivity
Computational fluid dynamics
Temperature distribution
temperature distribution
engineering

All Science Journal Classification (ASJC) codes

  • Nuclear and High Energy Physics
  • Nuclear Energy and Engineering
  • Condensed Matter Physics

Cite this

Pellegrini, M. ; Endo, H. ; Merzari, Elia ; Ninokata, H. / Algebraic turbulent heat flux model for prediction of thermal stratification in piping systems. In: Nuclear Technology. 2013 ; Vol. 181, No. 1. pp. 144-156.
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Algebraic turbulent heat flux model for prediction of thermal stratification in piping systems. / Pellegrini, M.; Endo, H.; Merzari, Elia; Ninokata, H.

In: Nuclear Technology, Vol. 181, No. 1, 01.01.2013, p. 144-156.

Research output: Contribution to journalArticle

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