775 results about "Porosity" patented technology

The invention provides an engineering construction defect automatic detection and classification method based on deep learning, and the method comprises the steps: obtaining a welding seam surface image through the shooting of an unmanned plane, and carrying out the denoising and illumination normalization processing of the welding seam surface image, and obtaining a standardized image; welding seam surface texture features are extracted from the standardized image, a convolutional neural network is adopted to analyze the spatial distribution characteristics of textures, and vectorization processing is carried out to obtain texture feature vectors; segmenting a weld surface corresponding to abnormal region distribution by adopting a region growing algorithm, and analyzing pore and weld discontinuity in combination with the texture feature vector to obtain a defect candidate region; performing threshold division on the sizes and the numbers of the defects according to the defect types and the feature vectors of the candidate regions to obtain a severity grading result of each type of defects; and severity features are extracted from a grading result, and a Bayesian network is adopted to fuse texture feature vectors and defect type labels to obtain a welding quality evaluation score.

The invention relates to the technical field of petroleum and natural gas engineering, and discloses an oil and gas reservoir optimized mining method based on multi-modal data, which comprises the following steps: constructing an oil and gas reservoir multi-modal data acquisition system, seismic wave field data, logging interpretation data, production dynamic data, micro-seismic monitoring data, underground temperature and pressure time sequence data and shaft structure parameter data are obtained through the acquisition system; and performing space-time alignment processing on the acquired multi-modal data, establishing a unified geological coordinate system and a time reference, and eliminating data isomerism caused by different acquisition frequencies and spatial resolutions. A six-dimensional heterogeneous data acquisition system covering a seismic wave field, well logging interpretation, production dynamics, micro-seismic monitoring, an underground temperature and pressure time sequence and shaft structure parameters is constructed, so that the depiction precision of a reservoir porosity field, a permeability field, a saturation field and a pressure field is essentially improved.

The invention relates to the field of digital core modeling, in particular to a stomatal basalt three-dimensional digital core reconstruction method, which comprises the following steps: extracting target characteristic parameters from CT (Computed Tomography) scanning gray volume data of a stomatal basalt sample, the target characteristic parameters comprising porosity, cluster number, cluster size statistics, spatial uniformity index and simplified compactness; generating an initial three-dimensional digital core model according to the target characteristic parameters; carrying out iterative optimization on the initial three-dimensional digital core model by utilizing a self-adaptive Markov chain-Monte Carlo algorithm so as to enable cluster features of the optimized three-dimensional digital core model to approach target feature parameters; and performing curvature smoothing post-processing on the optimized three-dimensional digital core model to obtain the pore basalt three-dimensional digital core model. The model not only is highly matched with real pore basalt in the aspect of macroscopic statistical characteristics, but also shows natural and smooth curved surface characteristics in the aspect of microscopic pore boundary morphology, and provides a reliable digital basis for subsequent rock physical property analysis.

Disclosed in the present invention is a rock porosity prediction method based on the inversion of few-shot while-drilling data. While-drilling parameters of a drilling rig during a laboratory or on-site drilling process are collected, wherein the while-drilling parameters comprise parameters such as torque M, thrust force F, rotation speed N, penetration rate V, drill pipe amplitude A and vibration acceleration a; different types of while-drilling parameter data which have been subjected to multiple instances of denoising processing are inputted into a BP-GA model for outlier removal, data augmentation and iterative calculation, so as to form a new while-drilling data set; and while-drilling parameter time-frequency domain feature maps of rocks having different porosities are inputted into a VG-CNN prediction model, an inversion model between while-drilling parameter time-frequency domain features and the porosities is obtained by means of training and learning, and finally inversion prediction is performed on the rock porosities on the basis of on-site real-time while-drilling parameters. The present method enables fast, accurate and quantitative inversion and prediction of rock porosities on the basis of a small amount of borehole while-drilling data.

The invention relates to the technical field of surface engineering, discloses a method and a system for preparing a yttrium fluoride composite ceramic coating through atmospheric plasma spraying, and aims to solve the problems that the yttrium fluoride coating generates a brittle aluminum fluoride layer on the surface of an aluminum substrate due to fluorine ion diffusion, so that the bonding strength is low, and the yttrium fluoride coating is easy to peel off and lose efficacy. The method comprises the following steps: sequentially carrying out mechanical polishing, ultrasonic cleaning and sand blasting roughening on an aluminum base material; preparing composite powder formed by mixing yttrium fluoride, yttrium oxide and nanometer aluminum oxide according to the mass ratio of 75: 20: 5; sequentially depositing a yttrium oxide transition layer, a composite barrier layer and a yttrium fluoride functional layer by adopting atmospheric plasma spraying; and finally carrying out vacuum post-heat treatment. According to the system, through the synergistic effect of the three layers of gradient structures, the transition layer forms an yttrium aluminate metallurgical bonding interface, the barrier layer inhibits fluorine ion diffusion through the dual mechanisms of nanometer aluminum oxide physical barrier and yttrium oxide chemical adsorption, and the functional layer guarantees the plasma erosion resistance. According to the method, the bonding strength of the coating is remarkably improved to 50 MPa or above, the porosity is lower than 3%, stripping is avoided under 500-hour high-energy plasma bombardment, the process cost is reduced by 40%, and the method is suitable for cavity protection of semiconductor etching equipment.

The invention provides a tap density prediction modeling method for a prebaked anode formula, which comprises the following steps: screening calcined coke into multiple particle sizes, measuring the tap density of each particle size, and obtaining physical property parameters; performing high-precision three-dimensional scanning on the representative particles, and constructing a digital model retaining geometric features such as edges and corners and textures; then, by adjusting the particle surface friction coefficient and the corner angle parameter, the deviation between the simulated porosity and an experimental value is within a preset range, and the feasibility of the model is verified; then, performing three-dimensional equal-proportion scaling on the reference fraction model, correcting physical parameters, and then, importing the reference fraction model into a discrete element system to simulate multi-fraction accumulation; and finally, based on the real-time porosity data, establishing a tap density prediction model of the irregular particle system by utilizing the negative correlation between the porosity and the tap density, and realizing the accurate prediction of the tap density under different proportions. The prediction accuracy of the tap density of the prebaked anode can be improved.

The invention discloses a method and equipment for evaluating the sensitivity of shale porosity to the pH value of a well-entering fluid, and the method comprises the steps: obtaining a plurality of groups of experimental data of a shale sample, the experimental data comprising a first initial porosity and a first pH value of the well-entering fluid corresponding to the shale sample; a three-dimensional response curved surface model of the porosity increment, the initial porosity and the pH value is constructed according to the experimental data, the initial porosity comprises the first initial porosity, and the pH value comprises the first pH value; according to the three-dimensional response curved surface model, the target initial porosity of the target shale and the target pH value of the well entering fluid corresponding to the target shale, the target porosity increment of the target shale is predicted; and evaluating the sensitivity of the target shale to the second pH value according to the target porosity increment. According to the technical scheme provided by the invention, the porosity increment of the target shale can be predicted, and the sensitivity of well entering fluids with different pH values can be quantitatively evaluated based on the porosity increment.

The invention discloses a high-content fly ash unfired water permeable brick and a preparation method thereof, and relates to the technical field of building materials, the unfired water permeable brick comprises the following raw materials by weight: 55-75 parts of fly ash, 20-35 parts of aggregate, 8-15 parts of a composite cementing material, 0.5-2 parts of toughening fiber, 1-3 parts of a pore regulator, 0.1-0.5 part of a surfactant, and 10-18 parts of water. Wherein the aggregate is 1-3mm waste ceramic particles and 2-5mm building recycled aggregate (1: 1-1: 2); and the rest components have specific proportions, specifications and modification requirements. According to the invention, 55-75 parts of F-type II-grade or higher high-content fly ash is matched with the waste ceramic particles and the pretreated building recycled aggregate to serve as the composite aggregate, solid waste is digested, natural resource dependence is reduced, and the method conforms to the direction of green building materials; by means of a modified composite fiber and composite gel system, the pressure resistance is larger than or equal to 25 MPa, the fracture resistance is larger than or equal to 3.5 MPa, the water permeability is larger than or equal to 1.5 * 10 cm / s, the freeze-thaw loss is smaller than or equal to 3.5%, and the grinding pit is smaller than or equal to 30 mm; through graded mixing, bidirectional pressurization and segmented maintenance, the porosity is kept to be 15%-25%, the percent of pass is increased, and the cost is reduced.

The invention discloses a coarse and fine particle inclusion photoelastic sample preparation and contact force chain network analysis method, and relates to the field of particle material mechanical tests, and the method comprises the following steps: calculating target void ratios under different coarse particle contents through a discrete element method; generating a corresponding numerical calculation sample according to the target void ratio and the preset coarse grain content, and exporting related parameters to prepare a coarse and fine grain inclusion photoelastic sample with the same initial compactness; in combination with non-polarization and polarized photoelastic images of the photoelastic sample, extracting intergranular contact force and constructing a contact force network; based on the contact force network, a strong contact force network is extracted and microscomic analysis is carried out, and force transmission characteristic comparison results under different coarse grain content conditions are obtained. According to the method, preparation efficiency of samples with different coarse grain contents and controllability of an initial state are realized, an influence rule of the coarse grain contents on a force chain structure and force transmission characteristics thereof is disclosed based on analysis of a contact force chain network, and the method is of great significance in researching a force transmission mechanism of a coarse and fine grain inclusion system and microstructure characteristics thereof.

The invention relates to the field of environmental analysis, and provides a gas hydrate three-phase coexistence region modeling method and system. The method comprises the following steps: acquiring three-dimensional seismic data and original logging data, and preprocessing the original logging data to obtain corrected logging data; respectively performing logging interpretation and structural interpretation according to the corrected logging data and the three-dimensional seismic data to obtain interpretation results; converting a structure interpretation result in the interpretation results into a three-dimensional geological structure model, and performing grid division on the research area by adopting a corner grid system to obtain a structure grid model; and performing attribute modeling on the constructed grid model based on variation function analysis, and predicting porosity and saturation in a three-dimensional space through a Kriging interpolation algorithm to obtain a three-phase coexistence region model. According to the method, the influence of complex geological conditions on the accuracy of the model is reduced, and the precision of the three-phase coexistence region model is remarkably improved.

A rock porosity prediction method based on small-sample while-drilling data inversion is provided, including: collecting while-drilling parameters during laboratory or field drilling processes, including parameters such as torque M, propulsion F, rotational speed N, drilling speed V, drill pipe amplitude A, and vibration acceleration a; inputting the different types of multi-stage denoised while-drilling parameter data into a backpropagation regression-genetic algorithm (BP-GA) model for discrete point elimination, data augmentation, and iterative calculation to form a new while-drilling dataset; inputting the time-frequency domain feature graphs of while-drilling parameters for rocks with different porosities into a rock porosity convolutional neural network (VG-CNN) prediction model, obtaining an inversion model between the time-frequency domain features of while-drilling parameters and porosity through training and learning, ultimately achieving inversion prediction of rock porosity according to real-time field while-drilling parameters.

The invention relates to the technical field of sand mold casting, and particularly discloses a gradient exhaust sand mold for an aluminum alloy thin-walled workpiece and a preparation method thereof.The sand mold comprises a cavity surface layer (with the hardness ranging from 90 HB to 95 HB), a transition layer (with the hardness ranging from 80 HB to 70 HB and a back sand layer (with the hardness ranging from 60 HB to 65 HB) which are arranged from inside to outside, and microporous ceramic exhaust rods (with the diameter ranging from 0.3 mm to 0.8 mm and the distance ranging from 1 mm to 3 mm) are embedded in the cavity surface layer; the exhaust rod is composed of a mullite fiber matrix and a nanometer gamma-AlO coating, the porosity is 40-50%, and the exhaust rod penetrates through the back sand layer to form a directional exhaust network. The preparation method comprises the following steps: mixing sand layer by layer (the cavity layer contains 1.0-1.5% of phenolic resin, and the back sand layer contains 0.4-0.6% of resin and 4-6% of starch); when sand is filled to the position 1-3 mm away from the surface of the cavity, an exhaust rod is implanted (the positioning precision is + / -0.1 mm); gradient compaction is carried out (the high pressure of a cavity is 3.0-4.0 MPa, the vibration of a transition area is 20-30 Hz, and the back sand airflow is 0.1-0.2 MPa); and carrying out microwave curing (2.5 to 3.5 kW, 60 to 120 s). The defects of hot cracks and air holes of the thin-wall part (smaller than or equal to 5 mm) are overcome synchronously, and the casting yield is increased to 95% or above.

A device and method for representing the foam porosity state of foamed lightweight soil with self-adjusting beams, and relates to the technical field of sound absorption coefficients measurement; the device includes a standing wave tube, a plurality of polyvinylidene fluoride piezoelectric films, a sensor, an exciter, a push-pull handle, an adjustable telescopic tube, a foamed lightweight soil detection material, a charge amplifier, a data memory, a data adapter, a signal generator, an adaptive power amplifier board, and a PC computer; the device of the invention has low cost, long service life, high measurement accuracy, relatively simple production process, and can be applied to different scenarios.

The invention discloses a rock sample bedding identification method and device based on machine learning, and the method comprises the steps: collecting and processing original rock sample bedding images with category information labels, and constructing a rock sample bedding image training data set; based on the training data set, a multi-feature fusion recognition model based on a convolutional neural network is constructed and trained, and the multi-feature fusion recognition model fuses rock sample posture features and multi-dimensional bedding features; and inputting a to-be-recognized target rock sample bedding image into the trained multi-feature fusion recognition model, and outputting a corresponding rock sample bedding recognition result. The method aims to focus on the characteristics of various different rock sample bedding, including the characteristics of diversity and high similarity of rock lithology, porosity and permeability, and a multi-feature fusion recognition model is constructed; according to the model, from the bedding of a rock sample, the posture characteristics and the multi-dimensional bedding characteristics of the rock sample are calculated and utilized respectively, so that high-precision extraction and recognition of different types of rock characteristics are ensured.

To suppress leakage of an inert gas from a gas passage.SOLUTION: A holding device that holds an object includes a first ceramic layer formed of ceramic, a plate-shaped second ceramic layer disposed on the first ceramic layer and formed of ceramic, an intermediate layer disposed between the first ceramic layer and the second ceramic layer, and a gas flow path penetrating the first ceramic layer, the intermediate layer, and the second ceramic layer, wherein the intermediate layer has an outer peripheral portion located on an outer side and a central portion located on an inner side in a direction orthogonal to a stacking direction of the first ceramic layer, the intermediate layer, and the second ceramic layer, the porosity of the outer peripheral portion is smaller than the porosity of the central portion.SELECTED DRAWING: Figure 2

The invention discloses a ceramic component gradient modified C / C-SiC-ZrC composite material and a preparation method thereof, and belongs to the technical field of carbon / carbon composite material matrix modification preparation, a carbon fiber preform and a heating element are placed in chemical liquid phase vaporization deposition equipment, a precursor solution is added until the carbon fiber preform is fully soaked, and a ceramic component gradient modified C / C-SiC-ZrC composite material is obtained; and carrying out chemical liquid phase vaporization deposition reaction to obtain the low-density C / C composite material with porosity in unidirectional gradient distribution. And putting the mixture into a graphite crucible with a carbon-rich area facing downwards and a carbon-less area facing upwards, completely putting the graphite crucible into the ceramic powder for modification, reacting and infiltrating, and cooling to room temperature to obtain the C / C-SiC-ZrC composite material with the gradient modified ceramic components. The end with high ceramic content endows the material with a high-temperature thermal protection function, the end with high pyrolytic carbon content can effectively conduct heat generated in a ceramic-rich area, and the end with low ceramic content can effectively conduct heat generated in a ceramic-rich area. Due to the gradient design from the ceramic-rich area to the carbon-rich area, the material has high-temperature oxidation resistance and ablation resistance and is light, and lightweight design of an aerospace thermal protection structure is facilitated.

The invention relates to a tight sandstone three-dimensional digital core modeling size determination method based on rock physics experiment constraints, and belongs to the technical field of three-dimensional digital core modeling. According to the method for determining the three-dimensional digital rock core modeling size, rock physical experiments serve as constraints, and it can be ensured that the modeling size can identify intergranular pores and is highly matched with rock physical parameters; and the representativeness of the modeling size is accurately evaluated by comparing the porosity and the mineral component content of the three-dimensional digital core with a conventional rock physical experiment result, and a powerful basis is provided for construction of a compact sandstone digital model.

Systems and methods for determining a diagenesis level in a reservoir for performing hydrocarbon extraction include receiving a set of open hole (OH) log data from one or more wells in the reservoir, the OH log data representing a subsurface of the reservoir; executing a diagenesis model to process the set of OH log data, the diagenesis model trained by thin-section image data correlated to labeled OH log data, the labeling identifying values for a quartz overgrowth rate (QOR), a clay coating rate (CCR), or a thin-section porosity in the subsurface based on a value in the OH log data; determining a prediction of a porosity of the reservoir, a permeability of the reservoir, or both the porosity and the permeability; and generating a control signal representing a recommendation to drill a well at a location in the reservoir.

The invention discloses a coal mine porosity calculation method for improving sequential Gaussian simulation under multi-source data fusion. On the basis of logging data preprocessing, logging curves of natural gamma, density, three-lateral resistivity and the like are synthesized, the high-organic-matter stratum is accurately discriminated, a volume physical model is constructed to explain the porosity of the rock stratum, a linear regression model is constructed to explain the porosity of the high-organic-matter stratum, and the porosity of the high-organic-matter stratum is accurately discriminated. After the two results are spliced and combined, abnormal sudden change points on a curve are eliminated through a curve smoothing algorithm, then the porosity curve, rock core data and the water temperature experiment result are normalized and mapped into a geological grid model, variation function analysis and parameter selection work are carried out, improved sequential Gaussian simulation and post-processing are carried out on the basis, and the geological grid model is obtained. And the reliability of the porosity attribute model is improved.

The invention provides a method for determining the spontaneous combustion evolution process of end slope coal of a strip mine, and belongs to the field of geotechnical engineering geological disaster prevention and control and the field of mine safety and environmental protection. Updating the porosity, the permeability and the range of the combustion space area in the pre-established three-dimensional geologic model by adopting the three-dimensional distribution of the porosity of the bending subsidence zone, the permeability of the fissure zone, the permeability of the caving zone and the porosity of the caving zone in the combustion space area; performing coal fire evolution simulation again according to the updated pre-established three-dimensional geologic model to obtain a coal fire development range, an updated real-time temperature field range and a gas concentration field; and if the combustion cannot be continued, outputting a final coal fire development range and an updated real-time temperature field range. According to the method, the efficiency and accuracy of open-pit mine end slope coal fire treatment are effectively improved.

The invention relates to the technical field of oil-gas exploration logging interpretation and evaluation, in particular to a compact glutenite reservoir quality determination method based on pore structure factors. The method comprises the following steps: calculating the porosity POR through the density; the method comprises the following steps: performing correlation fitting analysis on permeability and pore structure parameters by using mercury injection data of a compact glutenite reservoir, screening out parameters with high correlation, and constructing a pore structure factor KX; performing rendezvous analysis on the pore structure factor KX and conventional logging data, screening out logging data with high correlation, and constructing a reservoir pore structure factor KX comprehensive classification evaluation model; calculating the shale content Vsh through a neutron-density intersection method; and establishing a reservoir classification evaluation standard by using the pore structure factor KX, the shale content Vsh, the porosity POR and the lithologic factor H, and determining the quality of the compact glutenite reservoir. The method has the advantage of high accuracy.

The invention belongs to the technical field of tunnels, and particularly relates to a treatment method for a building door tunnel penetrating a karst underground river reach, which comprises the following steps: step 1, multi-source geophysical prospecting fusion investigation: aiming at the tunnel karst underground river reach and the range of 500m around the tunnel karst underground river reach; the method comprises the following steps of: delineating a karst abnormal area by adopting semi-aviation transient electromagnetism; screening a strong corrosion area by adopting a depression analysis method; verifying parameters of the abnormal area through surface drilling and coring; identifying surface hydrology, lithology and seepage data characteristics through unmanned aerial vehicle-mounted high-resolution multispectral and thermal infrared cooperative remote sensing; karst water dynamic conditions including underground water flow velocity, flow direction and permeability coefficient, corrosion evolution characteristics including cavern forming time and expansion rate, and key physical and mechanical parameters including cavern filler porosity, permeability coefficient, surrounding rock integrity coefficient, uniaxial compressive strength, elastic modulus and Poisson's ratio are obtained. According to the treatment method for the building door tunnel to penetrate through the karst underground river section, the karst space characteristics are clearly presented through the arrangement of the treatment method for the building door tunnel to penetrate through the karst underground river section.

The invention provides a laser cladding process parameter determination method based on finite element analogue simulation, and relates to the technical field of surface treatment. Comprising the following steps: importing a substrate material and a cladding layer material into finite element three-dimensional software to construct a corresponding finite element model; setting laser power, a preset temperature and a scanning path of the finite element model to obtain a finite element model of a variable process parameter set; performing finite element simulation by utilizing the final finite element model, and acquiring stress-strain data corresponding to each process parameter by utilizing a nonlinear heat conduction equation and an elastic-plastic stress-strain equation; and determining an optimal process parameter combination according to the stress-strain data. The method solves the problems that in the prior art, laser cladding Ni-60% WC composite powder lacks a systematic and accurate process parameter determination method when applied to the 45 steel surface, so that cracks, air holes and other defects are prone to being generated in a coating, and the comprehensive performance is difficult to stably improve.

The invention is suitable for the technical field of geophysical exploration, and provides a rock physics-driven time-frequency domain longitudinal wave velocity dispersion attribute prediction method, which comprises the following steps of: establishing a rock physics model; under the driving of the rock physical model, inverting the porosity of the microfractures in the well, calculating the skeleton elastic modulus of the rock containing the fractures, and predicting a frequency-dependent longitudinal wave velocity logging curve; constructing a time-frequency domain longitudinal wave velocity seismic inversion initial model; constructing a TF-AVO theoretical formula, developing a time-frequency domain longitudinal wave velocity seismic inversion method based on an L-BFGS algorithm, and performing longitudinal wave velocity inversion by taking the initial model as prior information; analyzing the relative change of the frequency-varying longitudinal wave speed under different frequencies, and quantitatively predicting the frequency dispersion attribute of the longitudinal wave speed; and on the basis of logging data, calibrating a longitudinal wave velocity dispersion attribute prediction result, and carrying out reservoir oil and gas detection. The method has higher precision and resolution, the stability and reliability of longitudinal wave velocity dispersion attribute prediction are remarkably improved, and the dependence on strong amplitude response is overcome.

The invention discloses a preparation method of a wear-resistant coating of a piston rod, and aims to solve the problems of low bonding strength, high porosity, easiness in oxidation, large residual stress and the like of an existing coating. The method comprises the following steps: firstly, carrying out alkaline oil removal and sand blasting roughening pretreatment on a piston rod matrix, and carrying out sand blasting for 5-10 minutes by adopting aluminum oxide sand grains of 120-200 meshes under the pressure of 0.4-0.6 MPa; then NiCrMo alloy powder with the thickness of 15-45 microns is sprayed through high velocity oxy-fuel to form a bottom layer with the thickness of 80-120 microns, and the binding force of the coating and a base body is enhanced; then, WC-Co-Cr composite ceramic powder with the mass fraction of WC being 70%-85% is subjected to laser cladding, a wear-resisting layer of 300-500 microns is prepared, and argon at the speed of 10-15 L / min is synchronously introduced to prevent oxidation; finally, under the vacuum degree of 1 * 10 <-3 >-1 * 10 <-2 > Pa, the temperature is increased to 400-500 DEG C at the speed of 5-10 DEG C / min, heat preservation is conducted for 2-3 h Through gradient coating design and parameter synergy, the compactness of the coating exceeds 99%, the hardness reaches HV1200-1500, the bonding strength exceeds 70 MPa, compared with a traditional process, the wear-resistant life is prolonged by 3.2 times, the salt spray corrosion resistance exceeds 1500 hours, hexavalent chromium pollution is avoided, and the coating has remarkable industrial application value.

The invention belongs to the field of carbon dioxide geological sequestration and oil-gas field development, and relates to a shale carbon dioxide adsorption expansion damage experiment method considering a hydration state, which comprises the following steps: processing a shale sample according to requirements; the shale is subjected to constant-humidity regulation and control pretreatment, and in the process, different relative humidity environments can be used for pretreatment, so that the influence of different clay mineral hydration interlayer spacing states on adsorption expansion is obtained; soaking the pretreated shale in supercritical carbon dioxide, adsorbing the sample when the temperature and pressure conditions reach a set value, soaking until the rock sample reaches adsorption saturation, and treating by using carbon dioxide with different pressures and temperature gradients; according to collection of sample microstructure and mechanical data, damage can be treated through crack initiation position comparison, porosity and gray scale quantitative analysis and macro-mechanical parameter evolution. The method provides an experimental method for carbon dioxide geological sequestration safety assessment and shale gas fracturing parameter optimization.

The invention belongs to the technical field of coal mining, and particularly relates to a key parameter design method for targeted grouting and filling pier stud water-preserved coal mining. The method comprises the steps that mine hydrogeology and mining geology data are collected, and the burial depth, the thickness, the physical and mechanical parameters and the gangue breaking and expanding coefficient of a coal rock layer are obtained; adopting discrete element numerical simulation to determine the caving zone height under the insufficient mining critical propulsion length; the drilling depth of the grouting drill hole and the caving zone void ratio are calculated; preparing and testing the mechanical strength and diffusion stacking angle of the grouting material in a laboratory; combining the critical coefficient of insufficient mining, applying a rock stratum subsidence probability integral method, and scientifically designing the interval, the radius and the grouting amount of filling pier columns; and finally, cement pier columns are formed in a caving zone through ground drilling and grouting, an overlying rock stratum is stably supported, and structural deformation of the aquifer is controlled. The method is simple in parameter design and high in accuracy, and space-time interference of a traditional filling process is avoided.

The invention provides a carbon dioxide multi-layer integration injection dynamic regulation and control method and device, and relates to the field of carbon dioxide geological sequestration, and the method comprises the steps: determining the optimal layer number and layer spacing distance of multi-layer integration injection based on obtained geological parameters, and obtaining a plurality of injection layers; according to the geological parameters and the length of the gas injection well, an interlayer allowable pressure difference is calculated in combination with a seepage mechanical formula, and spatial distribution parameters of all injection layers are determined; determining an inlet angle of an injection port corresponding to each injection layer; analyzing the porosity change rate between the injection layers and the coupling influence coefficient of the stress field change; and dynamically adjusting the opening degree of the injection port of each layer by adopting a model predictive control algorithm, and determining a delayed injection strategy according to a configured formation permeability grading standard. According to the method, the injection flow uniformity and the sealing efficiency can be improved, the interlayer fluid channeling risk is reduced, and accurate dynamic regulation and control of multi-layer unified injection are achieved.

The invention relates to the technical field of carbon sequestration geological engineering, and particularly discloses a CO2 water rock reaction induced permeability change evaluation method based on machine learning, which comprises the following steps: firstly, acquiring multi-focal plane image data of a reacted sample on a scanning electron microscope platform; automatically identifying a reaction area by using the trained U-Net instance model, and obtaining porosity and specific surface area information; corresponding calculation coefficients are automatically selected and matched based on the area-depth information of the corrosion holes, normalization calculation is carried out, and the permeability and the spatial distribution of the permeability are directly output. According to the method, destructive detection is not needed, quantitative characterization of the rock permeability physical property is achieved, the analysis accuracy and efficiency are remarkably improved, batch processing statistics is supported, and reliable data support is provided for carbon sequestration safety research and sequestration simulation.

The present invention belongs to the field of material performance simulation. Specifically disclosed is a method for constructing a relationship between the non-soluble deposit density and the corrosion rate on the basis of finite element simulation. In the method of the present invention, by means of establishing a finite element model, constructing a relationship between the non-soluble deposit density and the porosity and performing simulation analysis on corrosion behaviors under different non-soluble deposit density conditions, a relationship between the non-soluble deposit density and the corrosion rate is constructed. The method of the present invention can effectively predict corrosion behaviors of a material under different non-soluble deposit density conditions, can provide a scientific basis for material protection design, and has wide application prospects.