Determination Of Reasonable Flowing Pressure Of Low Permeability Reservoirs Of Daqing Oil Field

Low permeability reservoir start-up pressure gradient and stress sensitivity.In failure during the development process,fluid pressure is reduced,elastic-plastic deformation of rock skeleton,decrease of pore throat,the permeability reduction.Although late waterflooding process fluid pressure increases,but the reservoir permeability is only partially restored.Analysis,therefore,studied the permeability of low permeability reservoirs,the oil Wells in the early years of the oilfield development reasonable bottom-hole flowing pressure range,for the protection of the reservoir and low permeability oil field of subsequent development has very important significance.First by improving the existing liquid-solid coupling method,simulated formation fluid solid coupling process,a study of fluid pressure drop in different level of permeability of rock permeability damage rule,and fluid pressure rises in different level of permeability of rock permeability recovery law,according to the law of the minimum flow pressure at the early stage of the mining is given.At the same time improve the stress and displacement experiment device,the rock elastic-plastic between permeability and influence each other,and established a quantitative relationship between them.Through pore loss rate in low permeable oil fields to study the influence of the fluid through capacity,it is concluded that the change of porosity of oil-water two phase flow ability.Then based on the analysis and study of low permeability reservoir seepage mechanism and the non-darcy seepage law of fluid,established considering start-up pressure gradient and stress sensitivity of low permeability reservoirs three-dimensional three-phase non-darcy seepage flow model,and USES the finite difference method to discrete mathematical model.Is compiled on the basis of the application of Visual Basic considering start-up pressure gradient and stress sensitivity of low permeability oil reservoir numerical simulation software,at the same time has also established considering stress sensitivity and start-up pressure gradient of oil well productivity equation.According to different level of permeability of reservoir,putaohua reservoir numerical simulation software were used to simulate and productivity equation calculation method,determine the scope of the reasonable flowing pressure under different moisture content.The research results obtained in this paper is mainly suitable for putaohua reservoir eight oil production company,also to other similar oilfields has a certain guiding significance.