The Seepage Law And Exploit Index Prediction Research On The Pseudo Horizontal Wells Development

Special low permeability reservoir is low permeability and small pore throat,leading to low percolation ability and low capacity.Under the condition of buried deeply and low abundance,conventional development benefit is poor.Pseudo horizontal well technology is developed by fracturing technology and injection-production well spacing,combining with "build long fracture,large well spacing" development to improve reserves producing rate and oil recovery rate.The reasonable development of low permeability reservoirs is of great significance.At first,this paper uses reservoir numerical simulation method to study the percolation mechanism of pseudo crisscross horizontal well and the pattern well,water injection development and failure.Studied the seepage stage and contribution in pseudo horizontal well.Contrasting analysis of the seepage mechanism of pseudo horizontal wells,horizontal wells and vertical wells development,and investigating the impact of heterogeneity.Then on the basis of seepage law,through the data statistics and reservoir numerical simulation,the development index law analysis was carried out.Finally,by using multiple linear regression and the improved multiple linear regression method,developing the pseudo horizontal well index prediction model and check respectively,and comparing the two model.The results show that the spread indicators and recovery degree of pseudo crisscross pattern is larger.Pseudo horizontal well has three main stages of seepage including early linear flow,quasi radial flow and system linear flow,and the contribution of last stage is of 95% or more.Residual oil is mainly distributed in the near of well attachment,and is the focus of the late.The predict model by using the improved multiple linear regression method is more accurate.Research results can provide theoretical guidance and technical support for extra low permeability reservoir development by pseudo horizontal well.