58 results about "Pore scale" patented technology

The invention discloses a method for preparation of a bone hydroxyapatite-imitating bone repair material, nano hydroxyapatite ceramic powder and NH4HCO3 powder are mixed proportionally, after mixing, the powder is loaded into a gradient mold for mechanical pressing into a block pressed blank, the block pressed blank is put into a discharge plasma sintering furnace, heated to 950 DEG C and 1050 DEG C in the heating rate of 100 DEG / min, and then kept warm for 10-20min, and after demoulding, a nano scale bone gradient-imitating porous hydroxyapatite bone repair material is obtained. The nano scale bone gradient-imitating porous hydroxyapatite bone repair material is prepared by the method comprises outer and inner two layers, the porosity is 34% to 80%, and the pore scale is controllable in the range of 100-500mum, and the nano scale bone gradient-imitating porous hydroxyapatite bone repair material has the advantages of fine grain size, composition purity, no residual pore former, controllable mechanical properties and degradation rate and the like, and can be used as a good artificial bone tissue repair material.

The application discloses a three-dimensional pore scale structured grid model reconstruction method based on a rock micro CT image. According to the method, by digital image denoising and binarization processing, partitioning and extraction of pores and skeletons in the rock micro CT image are completed, and storage of image data is implemented in a form of a three-dimensional array matrix; and on the basis of a corresponding relationship of model grid unit bodies and image pixels in the aspect of space positions, independently developed codes are utilized to complete search and space position calibration of the pixels of pore phases and skeleton phases, a structured network mode of the skeletons and the pores is constructed by adopting the grid unit bodies with the same sizes with the pixels, and a final model obtained by surface grid growth and geometric remodeling can be directly used for numerical calculation. The three-dimensional pore scale structured grid model reconstruction method disclosed by the invention improves the defects of poor grid quality, distorted topological structure and the like of a conventional reconstructed model, can meet numerical simulation requirements of problems of seepage, deformation, heat transfer and the like, and has the important significance for promoting researches in the related fields of energy mining and geotechnical engineering.

The invention discloses a method for extracting and quantitatively characterizing core heterogeneity based on core CT image pore information, comprising the following steps: carrying out CT scanning experiment on a carbonate rock core to obtain a two-dimensional gray scale slice; carrying out binarization segmentation, filtering, denoising, optimization processing, superposition reconstruction forming and core peer-to-peer digital core on the obtained two-dimensional gray scale slice; processing the data of the digital rock core; establishing a contribution relation equation of the rock core dissolved pore parameters to the rock core heterogeneity by utilizing the calculation parameters according to the relation that the heterogeneity of the rock core and the ratio of the dissolved pore volume to the total volume of the rock core are in positive correlation and are in inverse correlation with the number of the dissolved pores; and establishing a standard variance of rock core dissolvedpore scale distribution according to the rock core dissolved pore scale and the heterogeneity of the rock core, and quantitatively obtaining the heterogeneity of the rock core. The heterogeneity of the rock is evaluated based on quantitative calculation of the pore attribute of the rock, and the result is accurate and reliable; and guidance is provided for oil and gas reservoir reserve calculation and development schemes.

The invention is a method of optimizing the injection of a fluid into a porous medium, using modelling the migration of the fluid within the medium having application for oil reservoir development. A reservoir model is constructed. In each cell of this the model, a PNM model representative of the pore network in the cell is constructed. The concentration of the fluid is then determined in each cell by solving the cell-scale reactive transport equation. Fluid concentration modifications at the level of the fluid/rock interface, at the pore scale, are therefore taken into account by means of the PNM models. Corrective coefficients for the reactive transport equation and a law between the permeability of the porous medium and the porosity of the porous medium are thus calculated. Finally, fluid injection is optimized as a function of the concentrations in each cell.

The present invention relates to a petrophysical modeling method and a system thereof. The method comprises the steps of: a. obtaining the rock mineral composition and content according to a composition and content equivalent skeleton modulus, and obtaining related information of a plurality of pores in the rock; b. modifying a KT rock physical model according to the relevant information of the multiple pores to obtain a modified model; c. calculating the dry rock skeleton modulus based on the modified model and the equivalent skeleton modulus; and d. performing fluid replacement to obtain saturated fluid porous media P-wave velocities, shear wave velocities and densities, in order to complete modeling. The modified KT model taking the size of pores into account describes the influence of the pore transverse and longitudinal ratio and the pore scale on the seismic wave velocity. Under the same porosity conditions, the P-wave velocity and the shear wave velocity increase along with the increase of the pore scale, and decrease along with the decrease of the transverse and longitudinal ratio.

Estimating petrophysical properties of a hydrocarbon reservoir traversed by at least one wellbore comprises obtaining at least one core sample from the wellbore and obtaining a three-dimensional (3D) porous solid image of the core sample. A 3D pore scale model is generated from the 3D porous solid image. A distribution of reservoir fluids in pores of the reservoir is simulated by a microhydrodynamic simulation using the 3D pore scale models of the core samples and at least one petrophysical property of the reservoir by a microscale modeling using the simulated distribution of the reservoir fluids is simulated by fitting the at least one simulated petrophysical property to well logging data at a depth corresponding to a depth of taking the core sample using free parameters. Governing parameters of the 3D pore scale models are extrapolated along a logged part of the wellbore and the at least one other petrophysical property is estimated by simulation.

The invention discloses a rock-soil body discrete element fluid-solid coupling numerical simulation method based on pore density flow. The method comprises the steps of generating a solid particle random accumulation model, subdividing and identifying a pore network, establishing a pore seepage equation, acting on solids by pore fluid and adjacent solid particles, acting on the pore fluid by solid displacement, and updating pore seepage parameters; repeating the steps until the solid particles are balanced and the seepage of the pore fluid is stable. According to the method, the calculated amount is greatly reduced, the pore fluid state equation is established, the temperature field and the seepage field are naturally coupled through density, the microscopic seepage equation is established by analogy of the macroscopic Darcy law to achieve pore seepage calculation, and the complex macroscopic phenomenon can be efficiently simulated based on the pore scale energy.

The invention provides a numerical simulation method for a hydraulic fracturing process of a single-fracture rock based on a pore density flow method, which comprises the following steps of: firstly, establishing a rock-soil body discrete element particle accumulation body, namely, establishing a basic initial stratum accumulation model by simulating a gravity deposition process of a real world; obtaining a material conforming to the property of a real physical world material through material training; dispersing a rock-soil body into mutually contacted solid particles, subdividing and identifying pores according to a particle accumulation skeleton, and establishing a hydraulic fracturing numerical model; and carrying out time step iterative calculation until the rock-soil body model is balanced, and outputting a simulation result. According to the method, fluid density and pressure changes caused by different prefabricated fracture angles and prefabricated fracture angle changes are considered, a very complex and high-cost hydraulic fracturing experiment can be efficiently simulated based on the pore size, complex macroscopic phenomena can be explained, and hydraulic fracturing effects under different prefabricated fractures can also be simulated.

The present application discloses a Thermal-Fluid-Solid Multi-Field Coupling Simulation Method Based on a Micro-Scale Reconstruction Model. The method comprises the steps that: based on the reconstructed pore-scale structured mesh model of rock, by using rock micro-CT images, the mathematical model of solid-solid-three-field coupling is established, and the prediction of rock pore structure evolution and flow characteristics by stress and temperature change is realized through numerical simulation. Different from the traditional macro-scale heat-solid-solid coupling theory, this method is based on the reconstruction model of pore scale, and reveals the interaction mechanism of solid multi-field coupling. It is not only helpful to predict the effect of stress and temperature parameters on the development effect, but also to promote the research of multi-field coupling in geotechnical engineering, such as underground nuclear waste disposal, CO2 sequestration and geothermal development, which can better guide the engineering practice.

The invention relates to a device and a method for measuring a Sherwood number between a gas and a liquid in a porous medium by applying CT (Computed Tomography). The device comprises a CT scanning system and a gas-liquid mass transfer system. The method comprises the following steps: first, controlling the temperature and the pressure of a reaction container to be constant; acquiring CT images that the volume of foam in the porous medium changes with time at different liquid injection flow rates and in different liquid injection directions by utilizing a CT scanning imaging technology; obtaining the gas concentration value of the liquid and the value of a two-phase interface specific surface area after the CT images are processed, so that the Sherwood number of mass transfer between the gas and the liquid in the porous medium is calculated. By controlling an experimental device, different liquid injection directions can be set during an experiment process, so that convenience is brought to the analysis of the influence on a gas-liquid interface shape and the Sherwood number numerical value caused by gravity. By applying the method and a measuring device thereof, the Sherwood number between the gas and the liquid under a pore scale can be obtained, so that the cognition of mass transfer rules of the two phase materials of the gas and the liquid is enhanced; basic physical property data are provided for the analysis of multi-phase multi-component migration rules in a stratum environment.

The invention provides a direct tracking method for pore scale motion of polymer gel particles. The direct tracking method for the pore scale motion of the polymer gel particles comprises the steps of1, solving a fluid field; 2, calculating stresses of sub-particles; 3, calculating motion of the sub-particles; 4, correcting fluid volume of a particle coverage region; and 5, returning to the step1 for continuing to solve the next time step, until a preset time stop condition is met. The direct tracking method for the pore scale motion of the polymer gel particles successfully realizes the influence of contact forces between the particles, contact forces between the particles and a wall and action forces of the particles and a fluid on particle motion and deformation, and successfully realizes direct tracking of a dynamic process of motion of a polymer gel particle oil flooding system in pores.

Performing of a chemical treatment of a near wellbore area may include extraction of a core sample representing a portion of a near wellbore area, obtaining a three-dimensional (3D) pore scale model of a core sample, determination of composition of a core sample, generation scenarios of chemical treatment that each include chemical agent, determination of rates of reaction between mineral comprising core sample and treatment fluids, determination of qualitative and quantitative composition of reaction system in equilibrium, simulation of chemical treatment process using 3D model of a core sample and data on chemical reactions between minerals and treatment fluids, analysis of the chemical treatment influence on transport properties of a core sample, selection of optimal treatment scenario. Further, an operation is performed using the selected treatment scenario.

The invention discloses a three-dimensional deformed face limitation-based face pore matching method. The method comprises the following steps that: two face images of the same person under differentangles are inputted, and each face image is preprocessed; a pore level scale invariant feature transform transformation algorithm is adopted to extract the features of the pore scales of the obtainedface images, so that the skin pore features of a plurality of pore feature points in the face images can be determined; five-sense organ positioning and three-dimensional deformed face fitting are performed on the obtained face images, three-dimensional deformed faces are embedded into the two face images through fitting; three-dimensional deformed face limitation is performed on the fitted face images; the key points of the extracted features of the pore scales are matched with the key points of the pore scales of the limited three-dimensional deformed faces; and a final matching result is obtained. With the method of the invention adopted, other screening steps are not required, matching is very precise, the accuracy of the matching can be improved, and the establishment of an accurate face pore database can be benefitted.

The invention discloses an unconventional reservoir multi-scale and multi-component digital rock core construction method. The method comprises the following steps: step 1, constructing a multi-scalethree-dimensional digital rock core fused with pore information of different scales; 2, constructing a multi-component digital rock core based on a rock core two-dimensional picture; and 3, nesting the multi-scale rock core fused with different pore scale information with the multi-component rock core, and constructing a multi-scale and multi-component unconventional reservoir three-dimensional digital rock core containing different scale pore information. According to the method, fusion of pore information of different scales is achieved, characterization of rock mineral components is achieved at the same time, the constructed result is beneficial for researching the elastic properties of tight sandstone and shale reservoirs and exploring the influence rules of different mineral components, cracks, stratification and the like on the elastic properties of the rock, and therefore exploratory research is conducted on the rock brittleness cause, and a basic theoretical support is providedfor tight sandstone and shale brittleness logging evaluation and even fracturing transformation research.

The embodiments of the invention provide a system and method for determining oil and water distribution. The method comprises the steps that a first computed tomography (CT) image and a second CT image of a rock core are obtained, the first CT image is the CT image of the rock core, the second CT image is the CT image when a water with added indicator is injected to the rock core, according to thefirst CT image, position alignment treatment and brightness normalization treatment are conducted on the second CT image, the treated second CT image is obtained, and according to the first CT imageand the treated second CT image, the oil-water distribution image of the state of the water with saturated addition of the indicator is obtained. By adopting the system and method for determining oiland water distribution, the oil-water distribution image of the pore scale of a reservoir stratum can be determined.

The invention belongs to the technical field of petroleum scientific research. Aiming at the current situation that the quantitative analysis of the saturation distribution of fluid in rock does not reach a pore scale, the invention provides a quantitative analysis device and method for the saturation spatial distribution of fluid in rock. The method comprises the following steps of: injecting liquid in the overburden pressure state (no liquid exists), performing three-dimensional imaging on a rock core to obtain D1 and D2,and performing three-dimensional registration on the D1 and D2; obtaining D3 matched with D1 through the sampling of the D2; determining a threshold T1 based on overburden pressure porosity, and converting the D1 into a gap-matrix binary matrix; determining a threshold T2 based on the total fluid saturation, and modifying the value of the corresponding pixel in the D1 according to the gray scale of the gap pixel in the D3; extracting a pore network based on the gap pixel of the D1 to obtain pores, pore throats and corresponding pixel lists; counting the number of pixels occupied by two fluids in the pores and the pore throats and the total number of pixels to obtain pore fluid saturation; and counting the number, spatial distribution and shape factor relationship of the pores under different fluid saturations. According to the method, the spatial distributionof the fluid saturation of the pore size in a rock core can be obtained nondestructively and quantitatively.

The invention relates to a method and device for predicting an oil-gas effective reservoir in sandstone. The method comprises the steps: recognizing a sandstone development region through the root-mean-square amplitude attribute of post-stack seismic data; recognizing pore sandstone development area with a certain pore scale in the sandstone development area through intersection inversion of natural gamma frequency division and longitudinal wave impedance, wherein the recognition precision is high; and finally carrying out oil-gas detection on the pore sandstone development area with a certain pore scale by utilizing the characteristics of low-frequency increase and high-frequency attenuation of the oil gas, and predicting the distribution area of the oil-gas effective sandstone, so that the distribution range of the sandstone oil-gas effective reservoir is finely described, sandstone porosity prediction from sandstone reservoir prediction is realized, oil and gas content detection is gradually deepened, and the prediction precision of sandstone oil and gas effective reservoirs is improved.