Study on explosion characteristics and microstructure correlation analysis of coal dust in the presence of various concentrations and particle sizes

In order to study the influence of microstructure parameters of coal dust on explosion characteristics, a spherical explosive device is employed to examine the explosion characteristics of coal dust with various low concentrations/particle sizes, and the microstructure change characteristics of solid products, the risk of re-explosion of gaseous products and the correlation between macroscopic explosion characteristics and microstructure are appropriately evaluated. The obtained results reveal that the and (d/d) rises with increasing the concentration. The smaller the particle size and the higher the concentration, the shorter the explosion time. A linear correlation can be observed between the flame propagation speed and both and . Furthermore, the oxygen consumption and combustible gas products increased with the concentration of coal dust, which increasing the risk of secondary explosion. After the explosion, branched-chains and aliphatic carbon chains increased, and the content of functional groups in different absorption peaks changed, in which the aliphatic and hydroxyl structures had a significant correlation with the explosion intensity. The objective of this study is to provide a robust theoretical foundation for future research and development in the field of coal dust explosion suppression technology.