Mechanism of coal aerosol explosion development in an experimental mine working

Abstract

Today there is not enough scientific data on the energy level and the velocity of an explosion in actual mine workings, which have a cross-sectional area larger than experimental mine workings. The objective of the paper is to justify the energy parameters of an explosion in actual mine workings based on the disclosure of the fire front development mechanism when coal dust explodes in an experimental mine working with a limited cross-sectional area. These studies can be the basis for choosing the speed of action and the strength of the means of the localization of dust explosions. The main research method is an experimental and analytical method, based on the analysis of the results of experimental explosions of coal dust in experimental mine workings and theoretical substantiation of the regularities of the development of the velocity and additional energy of the fire front with further extrapolation to the conditions of actual mine workings. It is proposed to supplement the mechanism of explosion development with an idea about the sections of development of explosion dynamics, i.e. initiation, dust explosion, crater, which determine the characteristic parameters of the explosive front velocity: maximum initiating velocity, average velocity, and maximum velocity in a crater. It was established that during methane initiation in the experimental mine working at the boundary between the initiation and dusting zones, there is a situation of a hybrid explosion of a mixture of methane and dust with air, which has its own velocity and energy indicators. A linear dependence of the energy generated during the coal aerosol explosion on the cross-sectional plane of the mine working was established. This makes it possible to use the results of testing the coal from certain deposits in small-scale experimental set-ups to justify the parameters of protective means for the actual mine workings. © 2023, University of Zagreb, Faculty of Mining, Geology and Petroleum Engineering. All rights reserved.