Forecasting the productivity of hydraulic fractured horizontal wells precisely is vital to develop low permeability gas and oil fields. The presented paper is based on the instantaneous point source function and potential superposition principle, considering the non-uniform flow distribution and the variable mass linear flow in the fractures of a fractured horizontal well. In the study a dynamic model of couple reservoir seepage and the fluid flow in fractures was built using a spatial-time discretization technique, and a solution method was also introduced. The results revealed that when regarding the inflow to the fracture as uniform and neglecting the pressure drop in the fractures, there may be huge deviation in the productivity calculation of a fractured horizontal well. Neglecting the pressure drop in the fractures may lead to a relatively high calculated value as compared to the actual production. The flow exhibited as an unsteady flow in the early stage, with the fracture segments which were closer to the horizontal wellbore showing a higher flow flux, while others had a lower flow rate. As producing time increase, the hydraulic fracturing horizontal well came to a pseudo-steady state phase, the flow distribution in the fractures tended to be uniform and steady. The daily output of hydraulic fractured horizontal well increases as fracture conductivity increases and there is optimized fracture conductivity consistent with the reservoir permeability.

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