Transient productivity prediction model of vertical fracture gas well

The flow process and filtration equations of gas in vertically fractured well was researched using the seepage theory of underground oil and gas, and then the corresponding mathematical model of each flow process was established. And then the transient productivity prediction formula of vertically fractured well was deduced based on this. The application of this production forecasting formula obtains that the error is 3.4% between the calculated value and the actual value in Jilin oilfield. The effect of formation parameters and fracture parameters, including formation permeability, formation pressure, gas reservoir thickness, crack length, fracture diverting capacity, on productivity of vertically fractured well were analyzed through the forecasting formula. The proposed of transient flow productivity prediction formula solves the problem of complicated calculation process and slow computation speed of conventional catchment source function, and realizes fast solution to seepage equation of vertically fractured well.