Mechanism of Gas Flow in Matrix-Fracture in Deep Fractured Tight Sandstone Gas Reservoirs

In order to investigate the gas flow law of deep fractured tight gas reservoirs, a gas flow physical simulation device for matrix-fracture system was developed. Moreover, a gas flow physical simulation method for high-temperature and high-pressure matrix-fracture system was established and was used to simulate the gas flow process from matrix to natural and artificial fractures, as well as the mass transfer process between matrix and fracture under different temperature and pressure conditions. The differences in gas flow behavior under different temperature and pressure conditions were compared, and the comprehensive influence of stress and flow pattern on gas flow law under high temperature and high pressure was clarified. The simulation results show that the gas flow and rock permeability are significantly affected by reservoir pressure and stress, while the temperature changes have a relatively minor impact on gas flow and permeability. In addition, cores with natural fractures are significantly affected by stress sensitivity and gas slippage effect. The findings of this study can provide a theoretical basis for the efficient development of deep fractured tight gas reservoirs.