Influence of Absorption of Thermal Radiation in the Surface Water Film on the Characteristics and Ignition Conditions

Abstract

The results of the mathematical modeling of homogeneous particle ignition process of coal-water fuel covered with water film have been presented in article. The set co-occurring physical (inert heating, evaporation of water film) and thermochemical (thermal degradation, inflammation) process have been considered. Heat inside the film has been considered as the model of radiation-conductive heat transfer. Delay times have been determined according to the results of numerical modeling of the ignition. It has been shown that the water film can have a significant impact on performance and the ignition conditions. It has been found that heating main fuel layer occurs in the process of evaporation of water film. For this reason, the next (after the evaporation of the water film) thermal preparation (coal heating, thermal decomposition of the organic part of the fuel) and inflammation occur faster.