the effect of fuel pyrolysis on the coal particle combustion: an analytical investigation
;Baghsheikhi Mostafa;Rahbari Alireza;Ashrafizadeh Seyed Mehdi;Bidabadi Mehdi
Nature2016Vol. 20pp. 279-289
105
mostafa2016thermalthe
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.