Dynamic Simulation And Optimization Of Mining And Excavation Planning And Ventilation System In Gas Outburst Mine

According to the characteristics of the medium-distance seam of combined mining in coaland gas outburst mine, on the basis of the summary and analysis of home and abroad researches,this article systemically analyzes the mining and excavation planning theory, the dynamicsimulation and optimal regulation of mine ventilation system by using the mining science, themine ventilation science, the graphic theory of mine ventilation network, the fluid mechanics,the nonlinear optimization theory, and the software development, computer graphics ofcomputer science. The main research contents and findings are illustrated as follows:(1) From the statistical analysis results, it is an exponential function between the gasextraction rate of drill hole per hundred meters and gas extraction period, and then thereasonable gas extraction period is determined. Using the average value of gas emission rate ofthe same shift output as a statistical sample of the current shift output in the fully mechanizedworking face, the power function between the shift output and absolute gas emission rate, aswell as nonuniform coefficients of gas emission are obtained. Furthermore, the exponentialfunction between the tunneling length and absolute gas emission is acquired in the heading facewith different tunneling speed. A modified forcasting model of different gas source is putforward based on the statistical method to forcast the gas emission rate in the working face.(2) On the basis of the general technical rules of the mining and excavation planning, thisarticle establishes the index system of the coal and gas outburst mine with the medium-distanceseam and combined mining technology, and puts forward the mining and excavation planningmethod based on variable fuzzy theory. After that, the expert system of mining and excavationplanning is development.(3) This article establishes the model of excavating and superseding state of blind heading,the model of advancing and superseding state of working face, the model of canceling the blindheading, the changing model of the resistance value of the working face in the mining andexcavation process, and the changing model of the underground required airflow of chamber.Combining with the static simulation of mine ventilation system, the dynamic simulation theoryof mine ventilation system based on mining and excavation plan is put forward. Furthermore,the dynamic simulation system of mine ventilation system is developed.(4)This article establishes the nonlinear optimization model of mine ventilation network.The objective function is composed of the smallest air power of main fans, the fewestregulation locations and minimum differential pressure of area air leakage passage of the gob;the variables are mixing of the air quantity of the cotree branches and the regulation resistanceof the regulable branch resistance; the inequality constraint conditions includes the lower and upper bound of the air velocity, the required air quantity of the chamber, the total fan pressure,the regulation air resistance of the roadway; the equality constraint conditions includes theKirchhoff's current law, Kirchhoff's voltage law and the characteristic curve of main fans. Then,the combination method of differential evolution algorithm and critical path is proposed in forsolving the mine ventilation optimization model. Furthermore, the data structure andprogramming of the algorithm is developed.Jinjia coal mine, which is the coal and gas outburst mine in Panjiang mining area, adoptsmedium-distance seam of combined mining method and the parallel ventilation system withmulti-shaft. From the application of research findings in Jinjia coal mine, the change law ofmain influencing factors of mining and excavation plan is obtained, and the optimal economyand security of5years mining and excavation planning is weaved. On this basis, the recentchanging of the mine ventilation system due to the mining and excavation is simulated byapplying the dynamic simulation theory of mine ventilation system theory. Combining with theoptimal regulation technology of mine ventilation system for controlling the gob air leakage,this theory and technology has an important practical significance on enhancing the minedisaster prevention and protecting the mine safety production.