THERMAL SCIENCE

International Scientific Journal

THE EFFECT OF FUEL PYROLYSIS ON THE COAL PARTICLE COMBUSTION: AN ANALYTICAL INVESTIGATION

ABSTRACT
The aim of this work is to analytically investigate the symmetrical combustion of an isolated coal particle with the fuel pyrolysis effect. The modelling concept of coal particles is similar to that of the liquid droplet combustion but in the case of coal devolatilization, the particles do not shrink like droplet does due to evaporation of liquid fuel. The rate of devolatilization of volatiles can be calculated using the equation that is similar to Arrhenius equation. This model is based on an assumption of combined quasi-steady and transient behaviour of the process and especially focuses on predicting the variations of temperature profile, radius of pyrolysis and transfer number. It is revealed that the entrance of pyrolysis effect into the governing equations leads to the reduction in the film radius and consequently a reduction in the stand-off ratio and transfer number.
KEYWORDS
PAPER SUBMITTED: 2014-06-22
PAPER REVISED: 2014-09-18
PAPER ACCEPTED: 2014-10-13
PUBLISHED ONLINE: 2014-11-08
DOI REFERENCE: https://doi.org/10.2298/TSCI140622126B
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2016, VOLUME 20, ISSUE 1, PAGES [279 - 289]
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