Simulation Of Gas Migration In Coal Seam Based On Three-dimensional LBM

At present, in china our energy structure only take coal as a leading resources to develop market and economy, because our country live in a unique industrial stage and special situation. For mines, especially coal asked for the latest and efficient management model on both technical and management, for the coal's running efficiently.Modern fluid simulation technology-Lattice Boltzmann method, bases on REV scale and is the effective combination of molecular dynamics and macroscopic physical research. This method eliminates the complex differential equations, is of programming easily and the boundary treatment diversification. Meanwhile, the method is used for much more complex system simulation.As the main factors in mine accidents, gas migration in coal seam is a fluid seepage through porous media made from coal. Meanwhile, liquid physical characteristics, media porosity and surrounding rock pressure play a lead role in the seepage system. The simulation is established for revealing the rules of the gas migration in coal seam and the gas emission in working place, which the gas migration is caused by the gas differential concentration due to working face excavation and the stress concentration of the upper rock layer. The fluid is from inner to working place in coal bed. The lattice Boltzmann seepage model is constructed without considering other factors, which the migration accord with the Darcy seepage rules. The whole simulation process is from the angle of velocity field and pressure field. This model has simulated the gas seepage velocity on the permeability influence caused by the upper rock layer, and on the effect of pressure relieved and fluid increased under the great gradient pressure variation. Meanwhile, the model has simulated the gas emission and the gas outburst. The actual situation of gas flow is exhibited from the angle of visualization.Finally, this paper has carried on the algorithm optimization and the algorithm tentative plan for the large-scale lattice points and complex situation. These operations are based on the LBM simulation of gas migration. Three-dimensional LBM Simulation based on Block-Coupling algorithm, can use effectively the computing resources to achieve large-scale simulation. Meanwhile, this paper considered that the grid computing system based on JAVA can do effectively the situation of large-scale, or complex situation, which the system support parallel Language-FORTRAN and the processing of lattice Boltzmann model.The research of this paper provides reference method and research foundation for mine mining and comprehensive treatment.