Frac-packing technology has been introduced to improve the development effect of weakly consolidated sandstone.It has double effects on increasing production and sand control.However,determining operation parameters o...Frac-packing technology has been introduced to improve the development effect of weakly consolidated sandstone.It has double effects on increasing production and sand control.However,determining operation parameters of frac-packing is the key factor due to the particularity of weakly consolidated sandstone.In order to study the mechanisms of hydraulic fracture propagation and reveal the effect of fracturing parameters on fracture morphology in weakly consolidated sandstone,finite element numerical model of fluid-solid coupling is established to carry out numerical simulation to analyze influences of mechanical characteristics,formation permeability,fracturing fluid injection rate and viscosity on fracture propagation.The result shows that lower elastic modulus is favorable for inducing short and wide fractures and controls the fracture length while Poisson ratio has almost no effect.Large injection rate and high viscosity of fracturing fluid are advantageous to fracture initiation and propagation.Suitable fractures are produced when the injection rate is approximate to3–4m3/min and fluid viscosity is over100mPa?s.The leak-off of fracturing fluid to formation is rising with the increase of formation permeability,which is adverse to fracture propagation.The work provides theoretical reference to determine the construction parameters for the frac-packing design in weakly consolidated reservoirs.展开更多
Faulted gas reservoirs are very common in reality,where some linear leaky faults divide the gas reservoir into several reservoir regions with distinct physical properties.This kind of gas reservoirs is also known as l...Faulted gas reservoirs are very common in reality,where some linear leaky faults divide the gas reservoir into several reservoir regions with distinct physical properties.This kind of gas reservoirs is also known as linear composite(LC)gas reservoirs.Although some analytical/semi-analytical models have been proposed to investigate pressure behaviors of producing wells in LC reservoirs based on the linear composite ideas,almost all of them focus on vertical wells and studies on multiple fractured horizontal wells are rare.After the pressure wave arrives at the leaky fault,pressure behaviors of multiple fractured horizontal wells will be affected by the leaky faults.Understanding the effect of leaky faults on pressure behaviors of multiple fractured horizontal wells is critical to the development design.Therefore,a semi-analytical model of finite-conductivity multiple fractured horizontal(FCMFH)wells in LC gas reservoirs is established based on Laplace-space superposition principle and fracture discrete method.The proposed model is validated against commercial numerical simulator.Type curves are obtained to study pressure characteristics and identify flow regimes.The effects of some parameters on type curves are discussed.The proposed model will have a profound effect on developing analytical/semi-analytical models for other complex well types in LC gas reservoirs.展开更多
基金Project(2016ZX05058-002-006)supported by National Science and Technology Major Projects of ChinaProject(2018CXTD346)supported by Innovative Research Team Program of Natural Science Foundation of Hainan Province,China
文摘Frac-packing technology has been introduced to improve the development effect of weakly consolidated sandstone.It has double effects on increasing production and sand control.However,determining operation parameters of frac-packing is the key factor due to the particularity of weakly consolidated sandstone.In order to study the mechanisms of hydraulic fracture propagation and reveal the effect of fracturing parameters on fracture morphology in weakly consolidated sandstone,finite element numerical model of fluid-solid coupling is established to carry out numerical simulation to analyze influences of mechanical characteristics,formation permeability,fracturing fluid injection rate and viscosity on fracture propagation.The result shows that lower elastic modulus is favorable for inducing short and wide fractures and controls the fracture length while Poisson ratio has almost no effect.Large injection rate and high viscosity of fracturing fluid are advantageous to fracture initiation and propagation.Suitable fractures are produced when the injection rate is approximate to3–4m3/min and fluid viscosity is over100mPa?s.The leak-off of fracturing fluid to formation is rising with the increase of formation permeability,which is adverse to fracture propagation.The work provides theoretical reference to determine the construction parameters for the frac-packing design in weakly consolidated reservoirs.
基金Project(2017QHZ031)supported by Scientific Research Starting Project of Southwest Petroleum University,ChinaProject(18TD0013)supported by Science and Technology Innovation Team of Education Department of Sichuan for Dynamical System and Its Applications,ChinaProject(2017CXTD02)supported by Youth Science and Technology Innovation Team of Southwest Petroleum University for Nonlinear Systems,China。
文摘Faulted gas reservoirs are very common in reality,where some linear leaky faults divide the gas reservoir into several reservoir regions with distinct physical properties.This kind of gas reservoirs is also known as linear composite(LC)gas reservoirs.Although some analytical/semi-analytical models have been proposed to investigate pressure behaviors of producing wells in LC reservoirs based on the linear composite ideas,almost all of them focus on vertical wells and studies on multiple fractured horizontal wells are rare.After the pressure wave arrives at the leaky fault,pressure behaviors of multiple fractured horizontal wells will be affected by the leaky faults.Understanding the effect of leaky faults on pressure behaviors of multiple fractured horizontal wells is critical to the development design.Therefore,a semi-analytical model of finite-conductivity multiple fractured horizontal(FCMFH)wells in LC gas reservoirs is established based on Laplace-space superposition principle and fracture discrete method.The proposed model is validated against commercial numerical simulator.Type curves are obtained to study pressure characteristics and identify flow regimes.The effects of some parameters on type curves are discussed.The proposed model will have a profound effect on developing analytical/semi-analytical models for other complex well types in LC gas reservoirs.
