Optimization of hydraulic fracturing considering non-Darcy flow in low permeability reservoirs

Key words:  low permeability reservoirs  non-Darcy flow  pressure swept region  well interference  reasonahle injecior-pro-ducer spacing  integral hydraulic fracturing  numerical simulation  optimization

Abstract:

A mathematical model was established considering non-Darcy flow in low permeability reservoirs as well as fracture flow conductivity failure, and the numerical solution was obtained based on the existing black oil simulator. A real Bohai reservoir model was developed to analyze hydraulic fracturing treatment on the basis of pressure propagation during well producing. The results show that the increase of drainage area after fracturing is the main factor of productivity improvement. When the well interference occurs between oil and water wells, the maximum drainage area of disturbance parts can directly reflect well pattern control degree and residual oil distribution. According to the drainage area that pressure spread speed begins to slow down during well producing, the reasonable injector-producer spacing is confirmed. The key factor of integral hydraulic fracturing is to make well system and fracture system be a perfect match. Taking the basic well unit as example, ihe optimum assembly of well unit and fracture system is gained when the angle between the fractures and the injection-production well line is above 70。,