Abstract: Based on flow characteristics of horizontal wells in naturally fractured reservoirs,vadose area is divided into two zones: near wellbore zone and far wellbore zone.The far wellbore zone is featured by its continuous homogeneity.In near wellbore zone,a coupling model is established considering fluid flow in fracture and horizaontal well simultaneously.Principles of potential superposition and mirror reflection as well as the concept of infinitesimal line congruence are used in the model.Combining flow characteristics of the far and near wellbore zones,a comprehensive computational method for fractured hoizontal well productivity is presented.A practical case is used to verify this method.Computational result shows that productivity of horizontal well calculated with this method is closer to actual flow rate than theoretical formula.Productivity of horizontal well increases as fracture density rises,but increment of productivity decreases as fracture density increases.

Key words: fractured reservoir, horizontal well, productivity, coupling model