Research On Considering Temperature Influence Gas-water Two-phase Flow Migration Rule

Coal seam gas-water two phase contains common influence of effective stress and temperature in seepage stage, experiment shows that according to effective stress principle, reasoning out the nonlinear relation of effective stress and permeability. Considering empirical Formula K = K0 exp(aσ), basing on massive experimental datas, it is presumed that K = f (σ, T) when K = k 0 e aσunder constant T , K = k 0 ebT under constantσ.On the base of coal seam gas-water migration basic assumption, establish gas-water two phase governing equations considering temperature influence in the coal seam and the influence of gas diffusion on seepage process. Using COMSOL Multiphysic analyzes gas-water two phase migration rule in the coal seam considering temperature action. Analyzes pressure field, velocity field and production of gas-water two phase on 600 day when T=25℃and T=40℃. In the fact that owing to gas-water two phase coupling effect considering temperature influence in coal seam, which leads to the fact that pressure difference of gas production center well becomes smaller and the surrounding production of gas-water decreases in 40 centidegree not 25 centidegree.Therefore, researching on low permeability coal seam percolation mechanism, revealing its seepage rule, on this basis estabilshing coal seam gas-water two phase migration rule mathematical model considering temperature influence, which not only has more important theoretical value, but also has more important practical significance for further research on low permeability coal seam percolation mechanism and gas reservoir efficient development.