Determining the permeability of tight rock with gas transient flow

The developed method evaluates the permeability under unsteady-state flow thus requires short period to determine flow capacity of low permeability rock. It reduces the measurement-time and experimental cost significantly. This new investigation is differentiated from the traditional methods such as Gas Research Institute (GRI), oscillating pulse, or pulse decay methods. Our method can overcome the disadvantages of other methods thus it indeed becomes an important supplement for industry. Further, this method has been rigorously developed from theoretical base, thus it is reliable and accurate for core analysis. The reproducibility of the proposed method is higher than oscillating pulse and pulse-decay methods.