Numerical comparison of the drag models of granular flows applied to the fast pyrolysis of biomass

K. Papadikis, Sai Gu*, A. Fivga, A. V. Bridgwater

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

38 Citations (Scopus)

Abstract

The paper presents a comparison between the different drag models for granular flows developed in the literature and the effect of each one of them on the fast pyrolysis of wood. The process takes place on an 100 g/h lab scale bubbling fluidized bed reactor located at Aston University. FLUENT 6.3 is used as the modeling framework of the fluidized bed hydrodynamics, while the fast pyrolysis of the discrete wood particles is incorporated as an external user defined function (UDF) hooked to FLUENT's main code structure. Three different drag models for granular flows are compared, namely the Gidaspow, Syamlal O'Brien, and Wen-Yu, already incorporated in FLUENT's main code, and their impact on particle trajectory, heat transfer, degradation rate, product yields, and char residence time is quantified. The Eulerian approach is used to model the bubbling behavior of the sand, which is treated as a continuum. Biomass reaction kinetics is modeled according to the literature using a two-stage, semiglobal model that takes into account secondary reactions.

Original languageEnglish
Pages (from-to)2133-2145
Number of pages13
JournalEnergy and Fuels
Volume24
Issue number3
DOIs
Publication statusPublished - 18 Mar 2010
Externally publishedYes

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