THE MATHEMATICAL MODELING OF FORMING THE TEMPERATURE FIELDS BY THE SPONTANEOUS HEATING OF ORGANIC SUBSTANCES
Purpose. Creation of the mathematical model of the processes of the low-temperature oxidation of the substances of organic origin on the basis of the mathematical model of their heating proposed and experimental data about thermal properties, dimensions of accumulations and heat exchange conditions.Methods. The methods are based on the mathematical model of the heterogeneous process of oxidation of the substances, experimental data of the NIIGD and analysis of literature sources.Results. To describe the dynamics of the temperatures of the organic substances by their spontaneous heating as a result of the oxidation reactions it is proposed to use the mathematical model of the low-temperature adsorption of the substances being accompanied by the first-order reactions. The analyticalsolution of the problem taking into account the heat exchange of the substance accumulation with the environment is given. The calculations of the temperatures of the coal accumulation were fulfilled in the mines of the Ist - IIIrd groups of the endogenous fire hazard and of the incubation period in 42 mines, where the fires occurred on the seams with the volume fraction of volatile matters from 8 up to 42 %. The dynamics of the temperatures by the chemical oxidation of five another various organic substances was calculated, and the portion of the reaction surface entering in the oxidation reactions was determined.Conclusions. The mathematical modeling of the dynamics of the temperatures of five types of the organic substances was fulfilled according to the experimental data of the NIIGD and literature sources. It is shown that the beginning of the spontaneous heating of the most substances occurs at the expense of microbiological processes during 3…35 twenty-four hours, whereat the temperature increase continues at the expense of the chemical oxidation reactions.