58 results about "Darcy" patented technology

A new approach is disclosed for measuring the pressure of tight gas reservoirs, using information obtain from continuous injection prior to hydraulic fracture stimulation. The technique can be obtained utilizing either bottom-hole or surface pressure gauges and properly instrumented surface injection pumps. The analysis is completed by plotting injection and rate data in a specialized form from terms arranged in Darcy's radial flow equation to obtain a curve or trend. The key component to proper application of this technique is to obtain both baseline and one or more calibration data sets. These calibration data sets are obtained by either increasing or decreasing the injection pressure and/or rate from the baseline data. Initial reservoir pressure is assumed, but the calibration data indicates if the guess was too high or low. Accurate estimates of reservoir pressure may be obtained in a few iterations.

The invention discloses a method for predicting the well yield of sealed, unsaturated oil reservoirs through elastic driving water-flooding extraction. The method includes: measuring the initial volume coefficient Boi of crude oil and the volume coefficient Bo of the crude oil under different pressure conditions, measuring the initial oil saturation Soi and the initial water saturation Swc of the rock core, generally measuring the in-place oil compression coefficient Co, the formation water compression coefficient Cw and the rock compression coefficient Cp, obtaining the rock effective compression coefficient Ceff according to the above parameters; measuring the oil geological reserves N and the reservoir pressure under a certain injection condition according to a matter balance equation, and finally measuring the yield of an oil well according to a plane radial flow Darcy equation, wherein the yield includes oil yield and water yield. The method supplements the correspondence between injected water and oil reservoir pressure change under the water-flooding extraction condition, accordingly can predict the daily oil yield and the daily water yield under the water-flooding extraction condition, and provides reference value for oil field production cost.

The invention relates to a computational simulation method of a flow slide catastrophe of a rock and soil material, belonging to the technical fields of computational rock and soil mechanics, geologic hazard prevention and control and geologic environment protection. Aiming at the limitation that the conventional grid-based computing method is only suitable for small-deformation analysis, the invention discloses a computational simulation method of an entire flow slide catastrophe process of the rock and soil material based on smoothed particle hydrodynamics (SPH). According to the method, a Navier-strokes equation is used as a control equation, solid phase and liquid phase of the rock and soil material are described by using a sub-load face Cambridge model and an incompressible fluid constitutive model respectively, porous medium theory and darcy law are introduced to calculate solid-liquid coupling acting force, and a computation model, which considers the full coupling of water and soil, of the flow slide catastrophe of the rock and soil material, is established. According to the computational simulation method, the entire process of large-deformation flow damage of the rock and soil material can be effectively represented, and the fluidization characteristic of the rock and soil material is captured, so that powerful scientific basis is provided for engineering design, engineering construction, disaster prevention and reduction and the like of high-risk areas of the flow slide disaster, and meanwhile, application of the computational rock and soil mechanics in the technical fields of actual engineering construction, geologic hazard prevention and control and the like is forcefully promoted.

The invention relates to a technology of oil-gas field development, particularly to a viscosity reducing effect evaluation method and device of heavy oil viscosity reducer under the stratum seepage condition. The method comprises the steps of determining the permeability rate and the experimental temperature according to the stratum condition, simultaneously injecting oil and water into a rock core in proportion through a seepage experiment and according to the water content, performing seepage experiment, recording the seepage pressure difference variation, evaluating the influence on oil and water stratum resistance by the viscosity reducer, calculating the apparent viscosity according to the Darcy law, comparing the variations of apparent viscosities of oil and water before and after the viscosity reducer is added, and evaluating the viscosity reducing effect of the viscosity reducer and the influence on the stratum seepage resistance by the viscosity reducer under the stratum seepage condition. The technology considers the difference of oil-water mixture in the conditions of stratum seepage and pipe flow, embodies the influence of a pore structure and a phase interface during the stratum seepage process, and is applicable to the evaluation of the heavy oil viscosity reducer under the stratum seepage condition.

The invention discloses a CO2 enhanced shale gas reservoir development dynamic simulation method based on a cross-scale multi-flow space gas transmission mechanism. The method comprises the steps: establishing a double-pore/double-seepage numerical model through a multi-component multi-phase three-dimensional numerical simulator; carrying out logarithm interval encryption on the hydraulic fractureby adopting a local grid encryption technology; establishing three flowing spaces of a matrix, a natural fracture and a hydraulic fracture in the shale reservoir; respectively calculating the density, viscosity and molecular weight of the single-component and multi-component natural gas on the basis of a density, viscosity and molecular weight calculation formula; calculating the apparent permeability of the corresponding single-component and multi-component natural gas; giving an average pore radius and a certain pressure interval; and enabling the multi-component multi-phase three-dimensional numerical simulator to call the corresponding natural gas permeability correction factor at each time step based on the calculated pressure, so the purpose of correcting the Darcy constitutive is achieved.

The invention relates to a shale gas reservoir fracturing horizontal well yield prediction method and system, and relates to the technical field of fracturing horizontal wells. According to the method, different diffusion modes of matrixes in different areas are considered, quasi-steady-state diffusion of the matrixes in a fracture network area is described by using Fick's first law, unsteady-state diffusion of the matrixes in a pure matrix area is described by using Fick's second law, seepage of a fracture network is described by using Darcy law, and the shale gas reservoir fracturing horizontal well yield is predicted under the condition that the matrixes are coupled with micro-fractures and pressure fractures are coupled with the micro-fractures, so that the prediction precision of theshale gas well yield is improved, and the actual flow law of shale gas reservoirs can be described more accurately.

Embodiments of the invention disclose a method, a device and equipment for processing wave propagation, wherein the method comprises the following steps of determining a dissipation function based onnon-Darcy flow in a fluid-containing porous medium on the basis of a constitutive relation of power-law fluid satisfied by fluid in a dense porous medium under the condition that the fluid in the dense porous medium is equivalent to the power-law fluid; taking a solid framework and non-flowing liquid in the dense porous medium as viscoelastic bodies, determining a potential energy function of thefluid-containing porous medium based on a viscoelastic stiffness coefficient, a strain invariant and volumetric strains of the solid framework and the fluid, and determining a kinetic energy functionof the fluid-containing porous medium based on the porosity, the average tortuosity of pores and pore throats in the dense porous medium, the densities of the solid and the fluid in the dense porous medium, and a fluid phase displacement and a solid phase displacement of the dense porous medium; and constructing a wave propagation model based on the non-Darcy flow according to the dissipation function, the potential energy function and the kinetic energy function of the fluid-containing porous medium.

The invention discloses a novel multi-scale finite element method for simultaneously simulating underground water flow and Darcy speed, which comprises the following steps of: setting scales of coarseand fine grid units, dividing a research area into the coarse grid units, and dividing the coarse grid units into the fine grid units to obtain a multi-scale grid; solving a degraded elliptic equation on the coarse mesh unit, and constructing a primary function; solving a Darcy equation and a speed matrix on the coarse mesh unit; obtaining a variation form of the problem by using a Galerkin method and a Green formula, and dispersing the variation form to the coarse mesh; substituting the Darcy law into variational components on each coarse mesh, converting a water head partial derivative terminto a speed term, linearly expressing the Darcy speed term by applying a coarse-scale solution of a water head by applying a speed matrix to obtain a unit stiffness matrix of the coarse mesh, and adding to obtain a total equation of the water head; and solving a total equation by using an effective matrix solution, and meanwhile, obtaining a Darcy speed value through a speed matrix. Compared with various classic methods, the novel multi-scale finite element method has higher efficiency.

The invention provides a method for calculating productivity of a high-pressure carbonate rock water-bearing gas reservoir gas well. The method comprises the following steps of: 1, establishing a productivity model of the high-pressure carbonate rock water-bearing gas reservoir gas well; 2, solving the productivity model, and solving expressions of a Darcy coefficient and a non-Darcy coefficient;3, determining a stress sensitivity coefficient B according to rock core permeability stress sensitivity experimental data regression; 4, calculating current water saturation according to logging original saturation and production data; 5, regressing a gas-water permeability curve, determining a gas-water permeability curve equation, and determining relative permeability Krg of gas and relative permeability Krw of water according to relative permeability curve equations of different reservoirs; and 6, calculating a Darcy coefficient A and a Darcy coefficient B, and determining a productivity equation expression. The method has the beneficial effects that by adopting the technical scheme provided by the invention, the productivity of gas wells of different medium reservoir gas wells of thehigh-pressure water-bearing gas reservoir under stress sensitivity and different water production modes can be accurately calculated.

The invention discloses a method and a device for dynamic liquid measurement of permeability of oil and gas reservoir rock. The method comprises the following steps of: applying periodic pulse pressure to fluid injected into a rock core by adopting a pulse displacement generation unit; measuring the pressure difference between two ends of the rock core; and determining the rock permeability basedon a Darcy law formula considering inertia. According to the method and the device, the periodic pulse pressure is applied to the injected fluid, and the Darcy law considering the inertia is obtained,so that the lack of understanding of the fluid fluidity change condition of the reservoir rock under external excitation of different frequencies is made up, the relationship between the rock permeability and the frequency change can be established through experimental observation, and the fluid fluidity is improved by utilizing the frequency of the external periodic pulse pressure correspondingto the peak permeability. Moreover, the scheme has universality in engineering, the influence of different rock gap structures and fluid components on the dynamic permeability can be obtained only byreplacing a rock core sample and/or fluid, and implementation and operation are convenient.

The invention discloses a shale reservoir induced heterogeneity dynamic evolution prediction method. The method comprises the following steps: correcting a pore with a non-circular cross section of ashale reservoir into a circular pore; carrying out quantitative characterization on pore size evolution by utilizing the pore equivalent diameter; calculating apparent permeability of different sections of the shale reservoir; calculating the apparent permeability of the shale reservoir by utilizing the apparent permeability of different sections and the pore proportions of different sections; obtaining a material balance equation of the shale reservoir based on the Darcy law of the apparent permeability; and solving the material balance equation to obtain the change relationship of the apparent permeability of the shale reservoir at different positions in the matrix along with time, and quantitatively characterizing the heterogeneous response and evolution in the matrix by utilizing the change relationship to realize the prediction of the induced heterogeneous dynamic evolution of the shale reservoir. According to the method, the development of the induced heterogeneity dynamic evaluation technology in the shale reservoir pressure relief development process can be promoted, and the understanding of the unsteady-state law in the shale reservoir development process is facilitated.

The invention discloses a tight reservoir liquid phase apparent permeability calculation method and device. The method comprises the steps of acquiring basic parameters of a tight reservoir to be analyzed, determining the corresponding relationship between the capillary length and the average pore diameter in the tight reservoir to be analyzed by adopting a fractal theory according to the basic parameters, constructing a single capillary nanopore liquid flow model in the tight reservoir to be analyzed according to the corresponding relationship, wherein the single capillary nanopore liquid flow model considers a slip effect, constructing a fluid flow model of the tight reservoir to be analyzed according to the single capillary nano-pore liquid flow model, and calculating the permeability of the tight reservoir to be analyzed according to the hydrodynamic model and a Darcy law. According to the calculation method, the slip effect is considered, so that the deviation generated by predicting the apparent permeability of the tight reservoir by adopting continuous fluid mechanics and slip-free boundary conditions is reduced, and the calculation accuracy of the liquid-phase apparent permeability of the tight reservoir is improved.

The invention provides a fractured shale permeability evaluation method, an evaluation model and a construction method thereof. The evaluation model evaluates the permeability of fractured shale by the evaluation method through the total permeability K of a shale reservoir, and the total permeability K of the shale reservoir is calculated through the shale permeability evaluation model; the construction method comprises the following steps: S1, deducing a permeability expression of a shale matrix based on a mixed fractal unit model and a Darcy law; S2, based on a fractal theory, establishing a fractal feature expression model of the opening and length of the natural fracture; S3, deriving a permeability expression of the natural fracture based on the model in the step S2 and the cubic law; S4, based on the permeability expression of the shale matrix and the permeability expression of the natural fracture, deducing the permeability expression of the whole shale reservoir. According to the method, the accuracy rate of predicting the permeability of the shale matrix and the natural fracture is up to 95% or above, and the evaluation cost is greatly saved.

The invention discloses a method and device for predicting the development effect of a shale gas well. The method comprises the following steps: obtaining slurry density and a slurry circulation temperature during a shale gas coring well full-diameter core coring process; collecting a desorption gas amount of the full-diameter rock core of the shale gas coring well at the slurry circulation temperature; establishing a diffusion model of desorption gas capacity and desorption time, and obtaining a unified diffusion equation; on the basis of the unified diffusion equation, calculating a rate of Darcy flow of free gas along a shale bedding fracture in the shale gas coring well full-diameter core coring process; based on the slurry density and the rate of Darcy flow, calculating a development effect evaluation coefficient. The invention can effectively avoid the necessity of long-term productivity data of the shale gas well, is suitable for shale gas wells in a low-exploration-degree region, has instantaneity in the application on the exploration of new regions, can provide first-time reference data, is also suitable for exploration of the shale gas wells in a mature region, and is a prediction method that is rapid, effective, convenient, and widely applicable.

The embodiment of the invention provides a fracture-vug type oil reservoir production dynamic characterization method, device and equipment and a storage medium. The method comprises the steps of: determining the fracture-vug unit type to which a target single well belongs; according to the generalized Darcy law, establishing a relation model between the periodic comprehensive water content and the periodic recovery ratio increasing amplitude of the target single well under multi-round water injection oil displacement; constructing a minimized target function according to the relation model; taking the observation value of the periodic comprehensive moisture content of the target single well as input, solving the minimized target function, and obtaining a determined relation model; and taking the relationship curve corresponding to the determined relationship model as the production dynamic law of the oil well corresponding to the fracture-cavity unit type under the condition of multi-round water injection oil replacement. According to the embodiment of the invention, the accuracy of dynamic characterization of multi-round water injection oil displacement production of the fracture-cavity type oil reservoir can be improved.

The invention relates to the technical field of kinematics and dynamics modeling, and discloses a method for establishing a liquid shaking model in a rectangular liquid tank with a porous elastic baffle. The porous elastic baffle is vertically arranged in the center of the rectangular liquid tank, and the top end of the porous elastic baffle is connected with a pair of mooring lines with the spring rigidity being K; the velocity potential of fluid in a tank is calculated by using a Laplace equation and a linearized free liquid level boundary equation based on a fluid dynamic analysis method of a two-dimensional linear potential theory; according to a Green formula matching characteristic function expansion method and a Darcy theorem, the bending moment and the shearing stress of liquid shaking on the baffle and the liquid height and the dynamic pressure in the liquid tank are solved, so that a specific analytical solution of important parameters of liquid shaking in the tank is obtained. The mathematical model established by the invention can effectively solve the problem of kinetic analysis of the rectangular liquid tank with the porous elastic baffle, and a relatively small weight load is applied to the tank body, so that the calculation process is simplified, and the accuracy of the model is improved.

The invention relates to the technical field of oil field exploration, and discloses a modeling method and system for a reservoir damaged by clay expansion and a method and system for determining the damage degree of the reservoir. The modeling method comprises the steps: determining the Darcy apparent velocity of fluid in a reservoir in a preset area of a to-be-diagnosed well; establishing a mass balance equation of the water molecules in the fluid according to the Darcy apparent velocity of the fluid and the diffusion coefficient of the water molecules in the fluid; according to the Fick diffusion law, establishing a diffusion equation that water molecules in the fluid diffuse into rocks in the reservoir; and according to the diffusion equation and the mass balance equation, determining a spatiotemporal evolution simulation equation of the clay expansion damaged reservoir, wherein the clay is the composition of the rock. The method can quantitatively simulate the four-dimensional spatio-temporal evolution process of reservoir damage characteristics caused by clay expansion, so that reservoir damage quantitative prediction and damage law spatio-temporal deduction are carried out on wells without reservoir damage.

The invention discloses a multi-scale finite element method-regional decomposition combination method for simulating groundwater flow and Darcy velocity. The method comprises the following steps: determining definite solution conditions of a groundwater flow problem, setting coarse and fine unit scales, and subdividing a research area; performing variational operation by using a Galerkin theory; solving a water head by applying a multi-scale finite element method; dividing a research region into single-medium sub-regions by using a region decomposition method, and decomposing an underground water Darcy velocity problem into sub-problems on the sub-regions; selecting a sub-problem, applying a Galerkin theory variation and combinding a multi-scale finite element method and a Galerkin method to obtain the Darcy velocity; acquiring the Darcy velocities of the sub-regions and the other side of the medium interface of the adjacent sub-regions by the refraction law as definite solution conditions of the adjacent sub-problems; and selecting the next sub-problem to solve. The groundwater flow and the Darcy velocity can be efficiently and accurately obtained, and the Darcy velocity can be ensured to accord with the refraction law at the groundwater medium interface, so that the invention of groundwater numerical simulation is enriched.

The invention relates to the technical field of oil field exploration, and discloses a modeling method and system for an emulsion blockage damaged reservoir and a method and system for determining the damage degree of the reservoir. The modeling method comprises the steps: determining the Darcy apparent velocity of fluid in a reservoir in a preset area of a to-be-diagnosed well is determined; determining the viscosity of the oil phase according to the temperature field of the reservoir and the function relationship between the viscosity and the temperature of the oil phase in the reservoir; according to the Darcy apparent velocity of the fluid, the viscosity of the oil phase and the emulsification condition of the fluid, determining the radius of an emulsion droplet formed by emulsification of the fluid; and according to the pore size distribution function of the pores of the reservoir and the radius of the emulsified liquid drop, determining a spatio-temporal evolution simulation equation of the emulsified blockage damaged reservoir. According to the method, the four-dimensional spatiotemporal evolution process of reservoir damage characteristics caused by emulsion blockage can be quantitatively simulated, so that reservoir damage quantitative prediction and damage law spatiotemporal deduction are carried out on wells without reservoir damage.