Influence Of Effective Fracture Permeability On The Productivity Of The Well With Vertical Hydraulic Fractures

When non-Darcy flow effects exist in the propped vertical fracture,seepage resistance significantly grows and gas production has a remarkable decrease.Aiming at the fact that non-Darcy flow effects exist in the fractures of fractured gas well and the lack of systematical investigation on its effect to fractured gas well productivity.Therefore the study of considering non-Darcy flow effects in the propped fracture in view of optimal fracture design for gas well and corresponding gas well production calculation have important theoretical and practical significance.Effective fracture permeability model considering non-Darcy flow,closure stress and gel damage effects has been built in this paper,and the concept of proppant number has been modified by effective fracture permeability to improve the methodology based on proppant number approach for optimal fracture treatment design,and the corresponding optimized Productivity model of gas well with vertical hydraulic fractures has been built.Moreover,fractured gas well productivity on certain fracture parameters has been built too.All the ? models have been evaluated by gas field data calculation which are important to effective fracture permeability calculation and non-Darcy flow effects assessment,to make better use and select ? models.Software has been compiled by using Visual Basic 6.0 code to evaluate and analyze the sensitivity of effective fracture permeability,calculate the fractured gas well productivity on certain fracture parameters to estimate the influence on productivity when the concept of effective fracture permeability is not used in the optimal fracture treatment design,and optimal fracture treatment design to this non-ideal condition in purpose of productivity maximization which can get the optimized Productivity that is more closed to actual condition and decrease the damage that ignore the most important variables affecting proppant pack permeability.Calculation shows that effective fracture permeability decreases?optimal fracture length shortens and optimum fracture width increases obviously when the non-Darcy flow effects exist in the fractures,and optimal fracture becomes shorter and wider when more damage factors on fractures have been considered in order to make up damages,the more accurate values of optimum fracture dimensions are available to Provide the technical guidance for the on-site fracturing operation.