44 results about "Permeability tensor" patented technology

The invention is a method for constructing a representation of a fluid reservoir traversed by a fracture network and by at least one well. The reservoir is discretized into a set of grid cells and the fractures are characterized by statistical parameters from observations of the reservoir. An equivalent permeability tensor and an average fracture opening is constructed from an image representative of the fracture network delimiting porous blocks and fractures is then deduced from the statistical parameters. A first elliptical boundary zone centered on the well and at least a second elliptical boundary zone centered on the well which form an elliptical ring with the elliptical boundary of the first zone are defined around the well. The image representative of the fracture network is simplified in a different manner for each of the zones which is used to construct the representation of the fluid reservoir.

The invention relates to the field of oil-gas field exploration and development, in particular to a fractured reservoir permeability tensor and anisotropy quantitative prediction method. On the basis of stress field numerical simulation, a static coordinate system and a dynamic coordinate system are integrated into a geodetic coordinate system by using the current occurrence of fractures, multiple groups of fracture permeability tensor quantitative prediction models are established, quantitative calculation formulas of the permeability principal direction and data are given, and the permeability of fractures in units in different directions is predicted by adjusting the rotation angle of the dynamic coordinate system. The fractured reservoir permeability tensor and anisotropy quantitative prediction method is based on strict mathematical algorithm derivation, a corresponding calculating program can be developed by using computer programming languages, fractured reservoir permeability tensor and anisotropy quantitative prediction is realized, the prediction cost is low, the operability is high, and the prediction result has certain guiding significance on determining the fault block permeability dominant direction, deploying and developing well patterns reasonably, and determining the spatial location relationship between an injection well and a producing well.

The invention is a method of determining all the components of an absolute permeability tensor of a porous medium sample from permeability measurements, obtained for example by placing the sample in a permeameter which is useful for fast determination of permeability anisotropies of rocks and detention of internal heterogeneities. A pressure difference ΔP is applied between the inlet and outlet faces of a laboratory rock sample, with zero flow conditions on the edges parallel to the mean flow obtained by confining it in a sheath under pressure. Starting from conventional permeability measurements in three directions and from the measurements of the two components of the viscous forces transverse to the sample, permeability tensor k can be “inverted” by numerical solution of the corresponding boundary-value problem. Since these quantities can be alternatively obtained from numerical solutions of the same flow in a heterogeneous medium, the method can also be used as an upscaling tool in a reservoir simulator.

Method for exploiting a fluid within an underground formation comprising a layer traversed by a fracture network and a well.

From property measurements relative to the layer, the fracture network is characterized by statistical parameters and a discrete fracture network model is constructed. For each well, three simplification zones surrounding the well are defined. From the statistical parameters, an equivalent permeability tensor and a parameter characterizing the orientation and the vertical continuity of the fractures are determined for each zone. For each zone, a simplification of the discrete fracture network model is determined as a function of the zone, the equivalent permeability tensor and the value of the parameter. An optimum exploitation scheme is defined for the formation fluid from the simplified fracture network model and a flow simulator.

Application: notably petroleum exploration and exploitation.

The invention discloses a method for calculating equivalent electromagnetic parameters of a wave absorbing honeycomb structure. The method specifically comprises the following steps: 1. deriving a strong perturbation theory framework; 2. substituting the electromagnetic parameters and structural parameters of the wave absorbing honeycomb structure into the strong perturbation theory framework in step 1 to obtain a substantially closed-form expression of effective permittivity tensor (shown in the description) and equivalent permeability tensor ( shown in the description) of the wave absorbing honeycomb structure, wherein the expression consists of an initial value part and a dispersion characteristic function; 3. expanding the initial value part obtained in step 2 , and simplifying a dispersion characteristic function expression to obtain a final closed-form expression for calculating the equivalent electromagnetic parameters of the wave absorbing honeycomb structure. Compared with the traditional calculation method, the method provided by the invention can reflect the dispersion characteristic of the equivalent electromagnetic parameters, and can be used for calculating the equivalent electromagnetic parameters of the wave absorbing honeycomb structure more accurately within a relatively wide frequency band.

The invention discloses a method for calculating and optimizing the permeability tensor of fractured rock mass based on measured structural plane parameters, which marks control points on the rock outcrop surface and takes pictures of the rock outcrop surface from different angles at the same time. The three-dimensional coordinates of the control points of the structural plane traces on the photographs are located according to the coordinates of the marked control points, and the homogeneous regions are divided according to the clustering degree of the control points on the structural plane traces. According to the coordinates of the control points of the structural plane traces, a three-dimensional model of the structural plane traces in the homogeneous region to be measured is established. According to the three-dimensional model of structural plane traces, the information of structural plane traces length, occurrence and spacing is extracted. Statistical analysis of trace length, occurrence and spacing of structural planes is carried out to determine the random distribution types and parameters obeyed by them. According to the type and parameter of random distribution, the permeability tensor of the homogeneous area to be measured is calculated. The invention improves the accuracy and efficiency of the structural plane information processing, and simultaneously improves thecalculation efficiency of the infiltration tensor and the optimal path identification in the calculation module.

The invention discloses a calculation method of a three-dimensional permeability tensor. According to the calculation method, on the basis of an analysis of two-dimensional fracture network permeability, a two-dimensional cross-section is rotated along a certain axle; penetration coefficients of the two-dimensional cross-section in each direction under different rotation angles are calculated; an elliptical sphere is drawn; and the three-dimensional permeability tensor is approximated with a regression analysis. As a one-dimensional line unit is used for simulating a fracture in the two-dimensional fracture network permeability calculation, complicated fracture processing work in a three-dimensional fracture network model is effectively avoided. When the fracture is calculated, dimensions of the equation are reduced from three dimensions to two dimensions, so that the number of the calculation and efficiency of the effective fracture are greatly improved.

The invention discloses a method for determination of anisotropic medium permeability parameters based on single-hole flow wave equation, comprising the steps of: first, determining the permeability parameter Keij of a single fracture through the single well flow wave equation; second, according to the fractured medium hydrodynamics theory, calculating the equivalent permeability coefficient Kei of same group discontinuities; at last, obtaining the anisotropic medium permeability parameter K based on the rock mass permeability tensor theory. By employing fractured medium hydrodynamics and oscillation test principles in the method, tests and data processing can be quickly finished on spot and the anisotropic medium permeability tensor can be obtained. The method can be used for parameter determination in study of pollutant migration, nuclear waste and carbon dioxide storage and underground heat motion, and also can be used in the field of, such as foundation safety inspection and large volume concrete safety inspection, having a great application and popularization value.

The invention relates to a permeability tensor test method and anisotropy quantification assessment method for columnar jointed rock. The permeability tensor test method includes: simulating actual columnar jointed rock to be measured to prepare similar materials with different cylinder inclination angles; measuring the permeability of similar materials; and according to the measured the permeability of similar materials, presenting the method for calculation of columnar jointed rock permeability tensor and permeability anisotropy quantification assessment. Based on the principle of tensor invariance, the method measures the permeability of similar materials with different cylinder inclination angles to obtain permeability tensor, permeability principal direction and osmotic principal value of the columnar jointed rock; and according to different types of actual columnar jointed rocks, corresponding similar materials can be prepred. The method solves the problem of indoor test for the measurement of natural rock permeability tensor and the problem of discreteness of testing results caused by the difference of natural rock, and has the advantages of low measurement cost, strong operability, accurate results and wide scope of application.

Method for exploiting a fluid in a subterranean formation comprising a network of fractures.

On the basis of measurements of properties relating to the formation, a meshed representation of the formation, and statistical parameters relating to the network of fractures, each mesh of the meshed representation is broken down into at least one unfractured matrix block and an equivalent permeability tensor of the network of fractures in the mesh concerned is determined. A matrix block characteristic dimension is then determined according to a relation that is a function at least of the eigenvalues of the equivalent permeability tensor. On the basis of the meshed representation, the characteristic dimension and a flow simulator, there is defined an optimum exploitation scheme for the fluid of the formation and said fluid is exploited as a function of the optimum exploitation scheme.

Application notably to oil exploration and exploitation.

The invention discloses an exponential mapping-based design method of a retro-reflective optical invisibility cloak. Firstly, a two-dimensional x-y plane coordinate system is established, and conformal mapping is carried out on coordinates in a range of which a radius is R2; a plane wave is emitted in parallel from an x-axial negative direction to an x-axial positive direction; linear mapping under polar coordinates is carried out on a second quadrant and a third quadrant of the coordinate system, where the invisibility cloak is located, to enable the radius range to be mapped to R1-R2 from 0-R2; a first quadrant of the coordinate system is mapped, and a fourth quadrant of the coordinate system is mapped; then a metric tensor of deformed space and a dielectric tensor and a permeability tensor of an impedance matching medium provided by transformation optics are calculated according to the impedance matching medium and equivalent relationships of space geometry; and finally, a Z component in the permeability tensor is normalized, and an artificial metamaterial is selected and used according to dielectric tensor distribution and permeability distribution to manufacture the optical invisibility cloak. The method solves problems of invisibility for objects and extraction of information of retro-reflection behind the objects.

The application provides a magnetotelluric forward method, a forward system, a storage medium, and an electronic device. The method includes: determining a calculation area, wherein the calculation area includes an anomalous body area; dividing the calculation area into multiple units; obtaining a conductivity tensor and a permeability tensor of each unit, wherein a conductivity and a permeabilityin the anomalous body area are different from those in calculation areas except the anomalous body area in the calculation area; and further determining an electric field and a magnetic field of thecalculation area, thereby determining an apparent resistivity and a phase of the earth surface in the calculation area. The impact of anisotropy of the conductivity and the permeability on a magnetotelluric response can be quantitatively analyzed by considering the anisotropy of the conductivity and the permeability in the magnetotelluric forward method. In addition, the forward system applying the forward method is more applicable to an actual magnetotelluric response, can provide a basis for anisotropy inversion of three-dimensional magnetotelluric conductivity and permeability, and therefore can have a wider application scope.

A method of non-destructive determination of a local magnetic permeability tensor of a material comprises testing by X-ray diffraction on a first surface to identify and measure any surface stress in the material; performing a calibration test using magnetostriction to identify any effect of any determined stress; subjecting the material to a magnetic field having a strength H and measuring a field of induction B on the surface at the selected location and repeating this step by using gradual increases of H until a saturated value is determined for B, to determine a distribution of magnetic domains at the selected location; repeating the determinations of saturated values for B at additional locations on each selected surface of the material; and using the saturated values and distribution of magnetic domains to derive the magnetic permeability tensor. The non-destructive method provides increased accuracy for stressed or unstressed materials of arbitrary shape.

The invention relates to a method for determining representative elementary volume (REV) of jointed rock mass. The method comprises the following steps of: selecting actual jointed rock mass of any size, and drawing a 3D (three-dimensional) digital model of the actual jointed rock mass; rotating the 3D digital model so as to ensure that the three-dimensional digital model forms different inclination angles relative to the horizontal direction, and performing 3D printing so as to prepare similar materials with inclination angles different from those of the actual jointed rock mass; measuring penetration rates Ka of the similar materials with different inclination angles (1/square root of Ka), establishing a coordinate axis, and drawing a closed curve by utilizing values of different inclination angle directions as distances between points to an original points; quantitatively analyzing whether permeability coefficients in different directions of the jointed rock mass conform to the permeability tensor rule according to the similarity between the closed curve and an oval; enlarging or reducing the volume of the selected actual jointed rock mass according to quantitative analysis result, repeating the above steps, and determining the REV of the actual jointed rock mass. The method is capable of fully simulating the actual jointed rock mass; the obtained REV value has slight difference from that of the actual jointed rock mass; compared with a numerical method, the method is capable of achieving relatively accurate REV of the rock mass.

The invention provides an anisotropy heterogeneity reservoir coalbed gas extraction well-completion technology selection method, and aims to comprehensively consider the anisotropy and heterogeneity of the coal bed permeability and scientifically select the coalbed gas extraction well-completion technology based on the coal bed permeability main permeability tensor. In order to achieve the purpose, the technical scheme is adopted. According to the technical scheme, firstly the location for testing the coal bed permeability is determined according to a geological map of target coal bed, then the main permeability tensor of each position is measured, that is, the main permeability direction and the main permeability value are measured, and then the geometric mean permeability of each location is calculated; according to the distribution of geometric mean permeability, the entire coal bed is divided into a plurality of blocks, and the well-completion technology for coalbed gas extractionin each block is determined according to the order of magnitude of the geometric mean permeability; and finally, the well-completion technology is further optimized according to the main permeabilitydirection. The technical scheme of the anisotropy heterogeneity reservoir coalbed gas extraction well-completion technology selection method is tightly close to the actual coalbed gas reservoir condition. Based on the coalbed permeability tensor which determines the key factors for the success or failure of coalbed gas extraction, the anisotropy and heterogeneity of the coalbed permeability are comprehensively considered, then the well-completion technology of coalbed gas extraction is selected, so that a solid theoretical basis is provided for the selection of coalbed gas extraction well-completion technology, and the scientificity of the selection of the coalbed gas extraction well-completion technology is improved.

The invention relates to the field of oil and gas field development, and discloses a true three-dimensional anisotropic permeability tensor testing device and a testing method thereof.The true three-dimensional anisotropic permeability tensor testing device comprises a square core holder used for fixing a to-be-tested cubic core and conducting one-dimensional constant-speed displacement on the to-be-tested cubic core in three different directions through fluid, measuring the injection-production pressure and the central pressure of the closed boundary surface; the confining pressure pump is used for pressurizing the square core holder; the displacement pump is used for adding fluid into the square core holder; and the processor is used for obtaining a passive pressure difference ratio according to the injection-production pressure and the central pressure of the closed boundary surface, substituting the passive pressure difference ratio into a pre-established three-dimensional full-tensor permeability intelligent chart, and performing fitting calculation to obtain a real three-dimensional permeability tensor rate of the cubic core to be measured. Therefore, through the interaction of the square core holder, the confining pressure pump, the displacement pump and the processor, the accurate core three-dimensional permeability tensor can be obtained, the operation is simple, the reliability is strong, and the applicability is high.

The invention relates to the technical field of hydrate tests, in particular to a hydrate porous medium synthesis device and a permeability tensor test system and a method thereof. The hydrate porous medium synthesis device comprises a body and a plurality of through-flow mechanisms, a synthesis space is formed in the body; each through-flow mechanism comprises an inflow channel and an outflow channel which are formed in the body in the preset through-flow direction, and the preset through-flow directions of the multiple through-flow mechanisms are different in pairs. The inflow channel and the outflow channel of each through-flow mechanism are arranged on the two sides of the synthesis space respectively, so that test fluid sequentially flows through the inflow channel, the synthesis space and the outflow channel. The hydrate porous medium permeability tensor test system comprises the hydrate porous medium synthesis device. The hydrate porous medium synthesis device is adopted in the hydrate porous medium permeability tensor test method. The hydrate porous medium synthesis device, the permeability tensor test system and the permeability tensor test method provide a structural basis for obtaining permeability tensors of the hydrate porous medium along multiple directions.