THERMAL SCIENCE

International Scientific Journal

TWO-DIMENSIONAL MATHEMATICAL MODEL OF LIQUID FUEL COMBUSTION IN BUBBLING FLUIDIZED BED APPLIED FOR A FLUIDIZED FURNACE NUMERICAL SIMULATION

ABSTRACT
Lately, experimental methods and numerical simulations are equally employed for the purpose of developing incineration BFB facilities. The paper presents the results of the two-dimensional CFD model of liquid fuel combustion in bubbling fluidized bed, applied for numerical simulation of a fluidized bed furnace. The numerical procedure is based on the two-fluid Euler-Euler approach, where the velocity field of the gas and particles are modeled in analogy to the kinetic gas theory. The proposed numerical model comprises energy equations for all three phases (gas, inert fluidized particles, and liquid fuel), as well as the transport equations of chemical components that are participating in the reactions of combustion and devolatilization. The model equations are solved applying a commercial CFD package, whereby the user sub-models were developed for heterogenic fluidized bed combustion of liquid fuels and for interphase drag forces for all three phases. The results of temperature field calculation were compared with the experiments, carried out in-house, on a BFB pilot-facility. The numerical experiments, based on the proposed mathematical model, have been used for the purposes of analyzing the impacts of various fuel flow rates, and fluidization numbers, on the combustion efficiency and on the temperature fields in the combustion zone. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR33042: Improvement of the industrial fluidized bed facility, in the scope of technology for energy efficient and environmentally feasible combustion of various waste materials in fluidized bed]
KEYWORDS
PAPER SUBMITTED: 2017-09-22
PAPER REVISED: 2017-10-10
PAPER ACCEPTED: 2017-12-18
PUBLISHED ONLINE: 2018-01-07
DOI REFERENCE: https://doi.org/10.2298/TSCI170922307N
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2018, VOLUME 22, ISSUE 2, PAGES [1121 - 1135]
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© 2018 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, 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