The influence of the structure heterogeneity on the characteristics and conditions of the coal-water fuel particles ignition in high temperature environment

摘要

The results of the experimental and numerical study of the coal-water fuel particles ignition (CWF) have been given, where the thermal properties (thermal conductivity (lambda), heat capacity (C), density (rho)) have been calculated using the different mathematical models. The heterogeneity and porosity of the structure of CWF have been taken into account in calculating lambda, C and rho. The influence of the shape, configuration and size of the pores on the thermal characteristics of coal-water fuel has been analyzed. It has been established that the effective thermal conductivity (lambda(eff)) is changed when there are the different ways of describing the thermophysical properties. It has been shown that increasing porosity (m(p)) of fuel during thermal decomposition affects lambda(eff) (or leads to the higher values of the effective coefficient of thermal conductivity, or to its decrease).