Characteristics of Porosity Distribution and Gas Migration in Different Layers of Comprehensive Working Face Goaf

The fracture field and permeability distribution model of comprehensive working face goaf was integrated upon the theoretical examination to investigate law gas migration accumulation characteristics, this has been applied mathematical in goaf. ANSYS FLUENT numerical simulation software used obtain characteristics its influencing factors analyze applicability solving features proliferation using porosity layer division results were as follows: around caving zone a little big, whereas middle small. almost equal along inclination strike symmetrical distribution. occurred at with an “O” shape. As gob height increased, tended be maximum value would shrink increase height. mass fraction showed growth “exponential function”, on air inlet side “Boltzmann outlet roadway manifested “linear function”. main leakage speed, negative pressure, different layers can more accurately simulate storage.