Heat transfer to a gas from densely packed beds of monodisperse spherical particles

Arpit Singhal, Schalk Cloete, Stefan Radl, Rosa Quinta Ferreira, Shahriar Amini

Research output: Contribution to journalArticleResearchpeer-review

Abstract

Particle resolved direct numerical simulation (PR-DNS) has emerged as a promising method to improve gas-particle heat transfer closure models. To date, this method has been applied in random and regular particle assemblies at comparably high void fractions. This paper presents a new methodology for deriving heat transfer correlations from PR-DNS of very dense particle packings relevant for packed bed applications. First particle packings were generated using the discrete element method (DEM). After geometric modifications in regions of close particle-particle proximity, a fine mesh with low cell skewness was created for PR-DNS. Grid independence and the effect of the geometry modification were thoroughly investigated. It was also established that steady state simulations are accurate for PR-DNS in this case. Simulations carried out in different assemblies of ∼100 particles showed significant variation of local transfer rates, implying that it is important to specify a confidence interval when reporting correlations derived from PR-DNS. A newly developed Nusselt number correlation predicts values in the lower range of predictions from literature correlations. This implies that the use of the currently available correlations may over-predict heat transfer in densely packed beds.
Original languageEnglish
Pages (from-to)27-37
Number of pages11
JournalChemical Engineering Journal
Volume314
DOIs
Publication statusPublished - 15 Apr 2017

Fingerprint

Direct numerical simulation
Packed beds
heat transfer
Gases
Heat transfer
gas
simulation
Void fraction
Nusselt number
Finite difference method
particle
Geometry
discrete element method
skewness
void
confidence interval

Keywords

  • Heat transfer
  • CFD-DEM
  • Packed bed reactors
  • caps-method
  • irect numerical simulation

ASJC Scopus subject areas

  • Fluid Flow and Transfer Processes
  • Process Chemistry and Technology

Fields of Expertise

  • Information, Communication & Computing
  • Mobility & Production

Cite this

Heat transfer to a gas from densely packed beds of monodisperse spherical particles. / Singhal, Arpit; Cloete, Schalk; Radl, Stefan; Ferreira, Rosa Quinta; Amini, Shahriar.

In: Chemical Engineering Journal, Vol. 314, 15.04.2017, p. 27-37.

Research output: Contribution to journalArticleResearchpeer-review

Singhal, Arpit ; Cloete, Schalk ; Radl, Stefan ; Ferreira, Rosa Quinta ; Amini, Shahriar. / Heat transfer to a gas from densely packed beds of monodisperse spherical particles. In: Chemical Engineering Journal. 2017 ; Vol. 314. pp. 27-37.
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