Modeling disturbances in a mine ventilation system caused by gas bursts

Abstract

The pressing need to devise measures to localize and reduce the harmful consequences of gas bursts in a network of mine workings is bringing to the forefront research on the properties of the ventilation system of a mine, regarded as a system affected by disturbing factors due to gas bursts. The need to use models to investigate the aerodynamic processes in a mine ventilation network with gasdynamic phenomena arises because the complex mining-technical conditions and the explosive medium in a coal pit practically exclude the possibility of carrying out any extensive experimental investigations of the dynamics of the prototype. A pit ventilation network is a nonlinear multiply connected system with distributed parameters which vary in a random manner with time. In respect of its topological structure and the variation of the parameters of the workings, a ventilation network is a complex nonsteady object subject to random disturbances (changes in the aerodynamic resistance, acoustic mass, acoustic compliance, rate of emission of toxic impurities, action of rock pressure, etc.). Owing to the complexity of the mathematical representation of the dynamic properties of a mine ventilation network and the technical difficulty of performing aerodynamic experiments in a mine, we resort to approximate mathematicalmore » models realized in the form of artificial long lines composed of chains of homotypic T-shaped quadrupoles with concentrated parameters.An analog model of the disturbances in a mine ventilation system due to a gas burst was made for the Severnaya pit of the Kuzbassugol production association which works a series of burst-prone seams including the Vladimirovskii seam in which 70 gas bursts have occurred.« less