Computer simulation of the air flow distribution in goaf regarding the use of inert gases and chemical agents

摘要

This paper presents the use of a computer method of the ventilation process simulation for the analysis of the flow distribution of air and gases in the area of wall mining work and the adjacent goaf.In workings and goaf,the complex issue of the formation of a gaseous atmosphere under variable ventilation conditions and an existing fire hazard level,with the possibility of feeding goaf with an additional carbon dioxide flux as the inertizing agent is considered.Some examples of the simulation of feeding goaf with carbon dioxide illustrating the different patterns of the distribution of the goaf atmosphere gases concentration,said distribution patterns being gas supply place dependent,have been presented.In addition,the impact of the additional sealing of goaf on the distribution level of the concentration of gases,the said sealing made from the wall side with chemical agents has also been considered.The capabilities of the VentGoaf computer simulation program,being the basis for our calculations,enable consideration of the use of the inert gases supplied to the goaf depending on:the location of the gas feeding the pipe outlet,tightness of the fire field,fire centre location,and spatial situation of the mined wall.It has been found that fire prevention elements,such as chemical sealing agents,are of great impact on the effectiveness of fire prevention.