THERMAL SCIENCE

International Scientific Journal

Milica R. Mladenović

,

Stevan Đ Nemoda

,

Milijana Paprika

,

Ana D. Marinković

APPLICATION OF ANALYTICAL AND CFD MODELS OF LIQUID FUELS COMBUSTION IN A FLUIDIZED BED

ABSTRACT
In Laboratory for Thermal Engineering and Energy of Institute Vinča, University of Belgrade, a two-dimensional CFD modeling procedure of numerical simulation of unconventional liquid fuel combustion in bubbling fluidized bed (BFB) has been developed. This procedure is based on a two-fluid Euler-Euler approach modeling a fluidized bed (FB) with the determination of the velocities field of gas and particulates in two-phase, granular flows, analog to the kinetic theory of gases (KTGF). This model describes in detail the unsteady motion of gas and solid phases, the formation and movement of bubbles with the combustion process in the FB, but temperature profiles calculated by the bed height differ to some extent from the experimentally obtained profiles. This discrepancy is probably due to the inability of a two-fluid CFD model to give a realistic simulation of the liquid fuel mixing in a fluidized bed. Therefore, an analytical model has been developed, where one of the basic assumptions is that the particles are mixed in the vertical direction of fluidized bed mainly by the bubble wakes. The proposed zonal type of calculating procedure is based on Davidson and Harrison two-phase model of the bubbling FB, where FB is divided into zones within which material and energy balances are set.
KEYWORDS
fluidized bed, combustion, Analytical Model, CFD model
PAPER SUBMITTED: 2018-02-26
PAPER REVISED: 2019-06-07
PAPER ACCEPTED: 2019-07-03
PUBLISHED ONLINE: 2019-08-10
DOI REFERENCE: https://doi.org/10.2298/TSCI180226317M
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2019, VOLUME 23, ISSUE Supplement 5, PAGES [S1627 - S1636]
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Application of analytical and CFD models of liquid fuels combustion in a fluidized bed

© 2024 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence