Simulation Studying On The Nonlinear Leakage Airflow-Coal-Heat Coupled Problems During The Spontaneous Combustion Of Porous Coal Seam Roadway Pillar

With theory researches and the computer numerical simulation method , this paper has studied the developing progress of the spontaneous combustion of coal roadway porous pillar and its parameters performance of air-coal-heat coupled , the nonlinear air-coal-heat coupled relationship formula of the self-heating roadway pillar under different conditions has been given , the nonlinear air-coal-heat coupled mathematics models of the air-leek permeability field and the temperature field has been established . According to the results of the models by way of real example, the lightness of these models has been tested.This paper has set up a geometric model for the purpose of studying of spontaneous combustion of coal pillar. The general model and its solving method of the spontaneous combustion of coal roadway porous pillar without the consideration of air-coal-heat coupled conditions has been given. The properties and its measuring method of parameters of O₂ consuming and heat release of the spontaneous combustion of roadway pillar have been discussed. The heating power action characteristics and the heating power ignition model of the spontaneous combustion of roadway pillar have been theoretically analyzed.This paper has analyzed the heat-coal deformation features and its dynamic developing process of the spontaneous combustion of roadway gob side pillar. The deformation field parameter's model of two dimensions strain problem for describing the spontaneous combustion of roadway pillar has been given. The air-coal-heat coupled relational expression between the heat stress σ^T of the spontaneous combustion of roadway pillar and its permeability coefficient k(φ) has been obtained, and the corrected air-coal-heat parameter-coupled models of the elastic-plastic deformation field of the spontaneous combustion of roadway pillar also have been obtained. By taking into account the air-coal-heat coupled factor of the temperature increasing field of the spontaneous combustion of roadway pillar, the air-coal-heat coupled numerical model of the air-leek field of the spontaneous combustion of roadway pillar has been established, and its numerical simulating solution has been obtained connecting with an example of the spontaneous combustion of roadway pillar in Yanzhou coal mining area.During the research process of the temperature increasing field of the spontaneous combustion of roadway pillar, By consideration of the air-coal-heat coupled factor in thetemperature increasing field of the spontaneous combustion of roadway pillar, the air-coal-heat coupled numerical model of the temperature increasing field of the spontaneous combustion of roadway pillar has been determined. The computing formula of the self-heating and combustion heat release source in the coupled models has been set up. The numerical simulating solution to the temperature increasing field model has been obtained connecting with an example of the spontaneous combustion of roadway pillar in Yanzhou coal mining area, and the model's reliability and validity also have been proved. By using the nonlinear air-coal-heat coupled numerical model of the spontaneous combustion of roadway pillar for the forecasting and prediction of the spontaneous combustion of roadway pillar, The spontaneous combustion disaster of roadway pillar could be effectively avoid .This paper has tried a method of studying the process of spontaneous combustion of roadway pillar from the parameters air-coal-heat coupled relationship, explored a new way of studying the problems of the spontaneous combustion of coal seam, and played a positive role for the development of mine fire science.