The Research On Numerical Simulation Of Coalbed Methane

Numerical Simulation is one of the most important decision-making tools in coalbed methane engineering. On one hand it can apply to study the porous media permeation flow rules, on the other hand, the result of simulation can be provided to engineers as a theoretical basis in explorer program. With the development of computer industry and mathematical theory of computation, the urgent need of the energy industry make the dynamic simulation become more increasingly realistic. At present, there are a lot of business simulations such as Eclipse, WORKBENCH which is integrated with pre-process model, simulation model and post-process model. Though the advantages of these tools are obviously, the core part of the software can not reflect the complexity of characteristics of coalbed. So the part goal of this paper is to develop software which can solve these problems.Firstly, this paper analyses the storage, migration and production coalbed methane theory. Secondly, on the basis of achievements summarized and drew from previous researchers, author make the depth study of coalbed methane desorption, diffusion and percolation theory and then build the geology model which consider the factors of coal matrix porosity and permeability and capillary pressure changes. Then a three-dimensional, dual-porosity, non-equilibrium sorption, two-phase mathematical model has been established.At the same time, fully implicit numerical solution technique for this mathematical model is given in details, then simulation software is developed using IDL integrated with GUIBuilder tool. At last the article calculated and analyzed the how factors of porosity and permeability etc. effect the production of coalbed methane well and then gave same reasonable suggestions to extraction of coalbed methane.