1117 results about "Porous medium" patented technology

A porous media grouting test system and method taking temperature effects into consideration. The system comprises a porous media formation simulation model (1), a grouting system (2), a water level adjustment system, a formation temperature control system and a data analysis system, wherein the porous media formation simulation model (1) is used for simulating a porous media formation; the water level adjustment system and the formation temperature control system are used for simulating the conditions of different water saturation levels and different water temperatures and ground temperatures; and the data analysis system is used for comparing different time-series data collected by sensors such as a temperature sensor and a pressure sensor with data such as temperature data and pressure data that is obtained by means of coupled solving of a heat transfer equation and a momentum equation, so as to verify and analyze a grouting diffusion path. Free simulation of different water saturation levels is realized by means of a water level adjustment system, and simulation of different ground temperatures is realized by means of a formation temperature control system, thereby realizing the research on grouting diffusion under different water levels and different water temperatures and ground temperatures.

The invention relates to the technical field of hydrogen production, in particular to a bipolar plate runner structure-mass transfer efficiency parameter simulation optimization method. Comprising the steps that a flow channel structure is designed, specifically, a bipolar plate flow channel is constructed through a fractal tree-shaped network topological structure, the flow channel is composed of multiple stages of branch channels, the section size of each stage of branch channel is decreased progressively according to a self-similarity proportion, and a three-dimensional flow channel network with fractal dimensions is formed; multi-physics field coupling modeling: establishing a multi-physics field coupling model including fluid flow, electrochemical reaction and heat and mass transfer based on computational fluid mechanics and a finite element method, wherein the model considers a turbulence effect in a flow channel, interface impedance of a porous medium diffusion layer and reaction kinetic parameters at the same time; parameter sensitivity analysis: screening key parameters influencing mass transfer efficiency through orthogonal test design, including flow channel fractal dimension, branch angle, porosity and surface wettability parameters, and constructing a parameter response curved surface; the flow channel structure of the bipolar plate can be accurately optimized, and the mass transfer efficiency is effectively improved.

The invention discloses a field soil heavy metal pollution health risk dynamic assessment and intelligent early warning system, and relates to the technical field of soil environment monitoring. The system comprises a multi-source data acquisition unit, a data preprocessing unit, a risk calculation engine and a visual interaction terminal. The key technical point is that a dynamic field evolution analysis module and an adaptive grid rendering control module are introduced; the dynamic field evolution analysis module constructs a pollution potential energy field matrix representing a pollutant migration trend based on soil heavy metal concentration and hydrogeological parameters, and calculates a space-time gradient change vector of the pollution potential energy field matrix; and the latter dynamically adjusts the grid local density according to the gradient vector module value, and automatically encrypts the computational nodes in the region with severe risk change. In cooperation with a time sequence prediction deduction and feedback correction mechanism, the method can simulate the dynamic evolution of the pollution plume in the porous medium in real time, solves the problems that a migration rule is difficult to capture and the calculation efficiency of a uniform grid is low in traditional static evaluation, and achieves three-dimensional dynamic risk early warning with high precision and low calculation power consumption.

The invention provides a CO2 sequestration simulation method based on transfer learning and a physical information neural network, which aims at a geological carbon dioxide sequestration process by combining the transfer learning and the physical information neural network, and comprises the following steps of: simulating and generating data by using a Matlab oil reservoir simulation tool box, and constructing a neural network basic model; the physical law of carbon dioxide migration in the porous medium is trained and learned through coarse resolution, then fine tuning is performed on the generated actual geological model data by adopting a migration learning strategy to adapt to different geological structures and injection conditions, and a neural network loss function is embedded in combination with a Darwest equation and a mass conservation equation to obtain a carbon dioxide migration model. Compared with a traditional numerical simulation method, the method has the advantages that the calculation efficiency is remarkably improved while the prediction precision is kept, and the method is suitable for carbon dioxide sequestration optimization and environmental risk assessment under complex geological conditions and has good industrial popularization value and environmental benefits.

The embodiment of the invention relates to the technical field of new energy, and provides a multi-physics field coupling optimization method of a co-electrolysis system and a related product, and the method comprises the following steps: obtaining a coupling mathematical model and a fractal porous medium permeability model in the operation process of the co-electrolysis system; based on physical field parameters output by the electrochemical kinetics calculation model, the non-Darcy seepage simulation model and the thermal stress field calculation model, corrected control parameters of the co-electrolysis system are obtained; the optimized permeability is obtained by adjusting fractal parameters of the fractal porous medium permeability model; the optimized permeability is provided for a non-Darcy seepage simulation model to update flow field pressure distribution; based on the physical field parameters updated in real time by the electrochemical kinetics calculation model, the non-Darcy seepage simulation model and the thermal stress field calculation model, performing multi-objective optimization on the coupling mathematical model to obtain an optimized coupling mathematical model. According to the embodiment of the invention, multi-physical field coupling of the co-electrolysis system can be optimized, and the method is suitable for complex working condition regulation.

The invention provides a hydraulic fracture evolution simulation method and device and electronic equipment.The hydraulic fracture evolution simulation method comprises the steps that a damaged rock mass is divided into a plurality of different calculation areas, and a seepage control equation of each calculation area is determined; in combination with seepage anisotropy, determining a seepage tensor of porous medium seepage-stress coupling in each calculation area; associating the seepage control equations of all the calculation areas with phase fields to obtain a target seepage control equation; and determining the displacement, fluid pressure and phase field of the damaged rock mass based on the target seepage control equation. Through the deduced seepage-stress coupling phase field model, the strain energy is decomposed through spectral decomposition, it is guaranteed that crack propagation occurs under the energy generated by tensile strain, and the problem that an existing hydraulic crack research method is limited is solved.

The invention relates to an underground engineering construction design technology, discloses a method for analyzing the influence of underground excavation under-crossing on an existing subway station, and improves the efficiency and precision of analyzing the influence of underground excavation under-crossing construction on the existing subway station. The method comprises the steps that by defining a structure and geometrical shapes and material attributes of a stratum, boundary conditions and external loads are set, grid division is carried out, and a finite element three-dimensional basic calculation model is constructed; according to theories of porous media and the like, a multi-physical field coupling model of a seepage-deformation-temperature full coupling effect is constructed; the rigidity of the underground excavation vertical pile foundation is calculated, and the rigidity of the underground excavation vertical pile foundation is corrected based on the influence factors of the soil squeezing effect and the negative friction resistance; subsurface excavation construction is subdivided into a plurality of stages, structural stress, deformation and stratum displacement are calculated through an incremental method, and the timeliness of a supporting structure and the influence of different excavation modes on stratum disturbance are analyzed; and obtaining a structural response through finite element iteration solution, and judging the influence of underground excavation under-crossing on the existing subway station.

The embodiment of the invention provides a method for realizing long-distance signal transmission under the condition of a porous medium in a goaf. The method comprises the following steps: selecting a proper signal frequency range based on the physical characteristics of the porous medium in the goaf; designing a corresponding signal modulation mode according to the selected signal frequency range; the stability of a signal propagation path is enhanced through a relay node deployed in the goaf; modulation parameters are dynamically adjusted based on the signal quality fed back by the relay node to optimize the transmission effect. Through the scheme of the embodiment of the invention, the problem of how to optimize and select the signal frequency so as to solve the problem of too fast signal attenuation in the porous medium can be solved, and meanwhile, the problem of how to regulate and control the dielectric property of the transmission path so as to solve the delay problem caused by signal refraction and reflection can be solved; and the problem of bit error rate increase in long-distance transmission can be solved by adjusting the signal coding mode.

The invention relates to the technical field of porous medium seepage, and provides a gray grid Boltzmann porous medium seepage analysis method based on a CT image. According to the method, the equivalent porosity of a local node is determined according to the obtained normalized maximum gray value of a CT image of a porous medium and the normalized gray value of the local node; according to the equivalent porosity of the porous medium, an equivalent permeation model between the equivalent permeability of the local nodes of the porous medium and the normalized gray value of the local nodes of the porous medium is established, and then according to the relation between the permeability of the porous medium in the LBM lattice space and the continuous solid fraction during seepage of the porous medium and the equivalent permeation model, the permeability of the porous medium in the LBM lattice space is calculated. A mapping model between a continuous solid fraction and a normalized gray value is established, gray LBM simulation is directly carried out based on the CT gray value, errors caused by traditional structure simplification and interface fuzziness are effectively overcome, the physical accuracy of complex medium multi-field seepage is improved, and the application range of the complex medium multi-field seepage is widened.

The invention belongs to the technical field of fluid simulation, and relates to a simulation method for fish school swimming and water flow coupling in a culture net cage, which comprises the following steps: coupling a monomer fish motion model with a netting model, calculating monomer fish stress, obtaining fish school stress of the whole net cage, and calculating a porous medium coefficient of a fish school porous medium model; assuming: a, fish bodies in the net cage have the same specification and do not influence each other; b, when the fish schools move in an incident flow mode, all the fish schools are arranged and evenly distributed in the net cage in an incident flow mode; c, when the fish schools swim in the circumferential mode, the radial intervals are equal, and the fish schools are evenly distributed in the vertical direction. Based on the hypothesis, an imaginary volume force source item is added in the area where the fish school is located to approximate the choked flow effect of the fish school; and carrying out stress calculation to obtain the stress of the porous medium area. According to the method, the accuracy of the calculation model is ensured, meanwhile, the simulation complexity of movement of a large number of fish schools in the aquaculture net cage is reduced, and accurate simulation of flow fields in and around the aquaculture net cage under the influence of fish school swimming is achieved.

The invention provides experimental equipment and method for simulating filling and sealing of carbon dioxide in a goaf, and the experimental equipment comprises a simulation system, a slurry injection system, a gas injection system, a data acquisition and processing module, a recording, analyzing and displaying module and a data acquisition system. A simulated overlying strata of the simulation system naturally collapses to form a porous medium space model, slurry and carbon dioxide are injected into the porous medium space model through the slurry injection system and the gas injection system, and data acquisition is conducted on the curing process of the carbon dioxide through the data acquisition system; and the data is transmitted to the recording, analyzing and displaying module through the data collecting and processing module. According to the invention, the influence of carbon dioxide on the slurry solidification behavior and the solidification reaction penetration depth can be comprehensively researched, and a scientific basis is provided for optimizing material selection, proportion design and injection process parameters in practical engineering.

The invention discloses a three-dimensional micro-nano multistage micro-channel structure and a preparation method thereof, and the channel structure comprises a substrate, a nano honeycomb layer located on the surface of the substrate, and a Tesla valve micro-channel and a micron fence member formed on the nano honeycomb layer. The micron fence piece is provided with a plurality of rib columns which are close to each other and are arranged along the side wall direction of the Tesla valve micro-channel; the high wicking capacity of the nano porous medium and the macroscopic fluid guiding capacity of the micron channels are organically combined, so that fluid can be rapidly transported in the multi-stage channels, the transporting capacity and the heat exchange efficiency of liquid are effectively improved, especially during boiling, the liquid supplementing rate and the steam discharging rate can reach dynamic balance, and the heat exchange efficiency of the liquid is improved. The friction loss of gas-liquid two-phase flow is reduced, and different thermal management requirements are met; in addition, according to the preparation method, nano-first and micro-second processing is adopted, high compatibility of the structure morphology and the material interface is achieved, good repeatability and process window are achieved, and the preparation method is suitable for large-area preparation and industrial production.

The thermal protection structure comprises a first porous medium layer arranged on the arc-shaped wall face of the front edge of the aircraft and a plurality of second porous medium layers arranged on the upper wall face and the lower wall face of the front edge of the aircraft at intervals in the flow direction. Solid walls are arranged between the first porous medium layers and the second porous medium layers and between every two adjacent second porous medium layers; the porosity of each second porous medium layer is firstly increased and then reduced along the flow direction, and the porosity of the first porous medium layer is smaller than that of the second porous medium layer at the most upstream. The method is applied to the field of thermal protection of aircrafts, the problem of local overheating existing in a traditional sweating cooling technology is effectively solved through the synergistic effect of the intermittent sweating layout and the gradient porosity material, and the situation that the cooling efficiency is reduced due to overheating of a cooling agent is avoided.

The invention discloses a hydrate-containing porous medium resistivity model construction method considering hydrate heterogeneous distribution, and the method comprises the following steps: 1) manufacturing a rock core according to the rock composition of a target hydrate reservoir, and scanning the pore throat structure of the rock core through CT; 2) generating a hydrate in the core, and scanning the occurrence state of the hydrate through CT (Computed Tomography); 3) establishing a digital core model based on CT scanning data, and applying an electrostatic field; 4) changing hydrate saturation parameters in the model, and calculating the resistivity of the model through numerical simulation; 5) calculating the critical water saturation of the hydrate; and (6) fitting by taking the critical water saturation as a boundary to obtain a resistivity segmentation calculation model. According to the method, a hydrate-containing porous medium resistivity model is established based on a real rock core size, and an electric field simulation means is utilized to calculate a hydrate-containing porous medium resistivity value. In combination with CT scanning data, an undetermined coefficient of a porous medium resistivity calculation formula in a hydrate thermal decomposition experiment is obtained through electric field simulation, and a basis is provided for hydrate reservoir electric heating development.

The invention relates to a porous medium modeling method based on a Lagguerre-Voronoi method, and the method comprises the steps: firstly generating a group of sphere data with the sphere diameter in logarithmic normal distribution by utilizing MATLAB software; using LAMMPS software to randomly stack the group of spheres in the fixed cubic space to obtain the sphere center coordinate and diameter of each sphere; the method comprises the following steps: randomly stacking spheres, performing space division on the randomly stacked spheres by using a Lagguerre-Voronoi method to obtain a corresponding three-dimensional Lagguerre-Voronoi graph, retaining edges and vertexes of each sphere division space in the three-dimensional Lagguerre-Voronoi graph, and generating a porous medium skeleton based on the edges and vertexes of each sphere division space; and finally, establishing a porous medium model of a required framework section shape according to the porous medium framework. Compared with a commercially available commercial foam structure, the porous medium model established by the invention can reproduce an actual foam structure more truly, and internal pores have good performance in the aspects of disorder and connectivity.

The invention relates to the technical field of pure ammonia combustors, in particular to a catalytic auxiliary cracking plasma pure ammonia combustor and an operation method thereof. According to the technical scheme, the device comprises catalytic cracking areas, a purification area, a pre-combustion area, a main combustion area, an ammonia supply area and a waste heat system, the catalytic cracking areas are arranged on the two sides of a combustor and comprise an ammonia gas inlet channel and a catalytic reaction area internally provided with a porous medium, and a catalyst fixedly grows on the surface of the porous medium; the purification area is located outside the combustor and connected with an outlet of the catalytic cracking area through a pipeline, and selective separation membranes are arranged at the outlet end and the exhaust end of the purification area respectively; the pre-combustion areas are distributed on the two sides of the main combustion area, comprise air inlet channels and plasma igniters and communicate with an outlet of the purification area. According to the invention, the problems of ignition, stable combustion and low NOx emission of the ammonia fuel are solved, the unification of efficient energy utilization and industrial applicability is realized, and a key technical support is provided for large-scale application of the ammonia alternative fuel in an industrial kiln.

The invention discloses a parallel computing simulation method for thermal exploitation of a buried pipe well group in a geothermal reservoir, which comprises the following steps of: dispersing a grid volume unit of a buried pipe by adopting a parallel finite element unit method, and simplifying the buried pipe and circulating fluid in the pipe into a one-dimensional linear finite element unit; constructing a plurality of pipeline flow models arranged in an array, and combining the in-pipe one-dimensional linear units and the out-pipe three-dimensional volume units to obtain a well group type pipeline flow geometric model; a parallel finite element unit method is adopted to be combined with a non-isothermal pipeline flow physical field, an underground water seepage physical field and a porous medium heat transfer physical field to conduct multi-physical-field coupling, and a well group type pipeline flow numerical model is obtained; fluid flow and convective heat transfer in the buried pipe and pipe wall heat conduction are solved in a combined mode; and performing factor sensitivity analysis by changing different thermophysical parameters of the rock-soil body and heat exchange characteristic factors of the buried pipe well group. The invention provides a new method for researching fluid flowing and heat transfer behaviors of the buried pipe well group, and provides a new idea for optimal design and efficient simulation of thermal exploitation of the buried pipe well group in a geothermal reservoir.

The invention discloses a supported ozone catalyst for printing and dyeing wastewater treatment and a treatment process, and relates to the technical field of wastewater treatment, the supported ozone catalyst comprises an environmental response type porous medium, an active center and a biological enzyme modification layer; the environment-responsive porous medium is based on poly (N-isopropylacrylamide) grafted and modified mesoporous alumina, the initial aperture of the mesoporous alumina is 10-15nm, the grafting rate of poly (N-isopropylacrylamide) is 12-20%, and an active center is composed of a transition metal active center and quantum dots modified on the transition metal active center. The biological enzyme modified layer is obtained by carrying out deep biological modification on the surface of the catalyst by using laccase with oxidation-reduction activity. According to the invention, an environment-responsive porous medium is constructed by grafting mesoporous alumina with poly (N-isopropylacrylamide), so that the problems that a traditional fixed-aperture catalyst is low in mass transfer efficiency and poor in adaptability to working conditions, and the pollutant release efficiency is difficult to effectively improve under different temperature and pH conditions are solved.

The invention belongs to the technical field of porous medium combustors, and particularly relates to a model selection construction method of a periodic cell body structure of a porous medium combustor, which comprises the steps of constructing a heat transfer device, constructing a cell body unit to be selected, installing the cell body unit to be selected, measuring data parameters, analyzing results and the like. From a plurality of perspectives of convective heat transfer coefficient, area excellent factor, effective heat conductivity coefficient, longitudinal diffusion coefficient and the like, the performance of the porous medium burner can be influenced by using different periodic cell body structures under the condition of the same porosity; the invention further provides a model selection construction method for the periodic cell body structure when the porosity is the same, a theoretical basis is provided for model selection of the periodic cell body structure of the porous medium burner, and several periodic cell body structures recommended to be constructed and used under common porosity conditions are given.

The invention provides a porous medium combustor for stable combustion of ultralow-calorific-value gas, belongs to the technical field of combustors, and solves the problems that an existing combustor is low in heat recycling efficiency and air is not fully preheated before entering a combustion area. The combustor comprises a shell, a gradually-shrunk porous medium layer, a stable-combustion porous medium layer, a gradually-expanded porous medium layer, a premixing chamber, a fuel channel and an oxidizing agent channel, and the gradually-shrunk porous medium layer, the stable-combustion porous medium layer and the gradually-expanded porous medium layer are all located in the shell and are sequentially arranged from top to bottom; the premixing chamber is communicated with the lower part of the divergent porous medium layer; an outlet of the fuel channel is communicated with the premixing chamber; the oxidant channel surrounds the stable combustion porous medium layer and the divergent porous medium layer and is spirally arranged on the shell, an inlet of the oxidant channel is located above the stable combustion porous medium layer, and an outlet of the oxidant channel is communicated with the premixing chamber. The combustible limit of the low-heating-value fuel gas can be widened, stable and efficient utilization of the ultralow-heating-value fuel gas is achieved, and the heat recycling efficiency is improved.

The invention discloses a hydrogen leakage condition multi-parameter monitoring and identification and leakage rate deduction method and device, and relates to the technical field of hydrogen safety monitoring, and the method comprises the steps: obtaining multi-parameter sensing data; carrying out noise reduction processing on the multi-parameter sensing data; based on a temperature signal, a pressure signal and a fastening force signal in the denoised data, establishing a temperature-pressure-fastening force coupled physical model by adopting a porous medium model; performing short-time Fourier transform and variational mode decomposition on sound vibration signals in the denoised data to obtain characteristic parameters; based on the characteristic parameters, establishing an initial data sample set; adding the leakage rate and the concentration signal in the denoised data into the initial data sample set to obtain a data sample library; and establishing a multi-parameter leakage prediction model by using a convolutional neural network based on the data sample library and the physical model. According to the invention, the online real-time monitoring of the hydrogen leakage state, the accurate judgment of the leakage size and the rapid prediction of the leakage development trend can be realized.

The embodiment of the invention provides a surfactant synergistic flooding parameter optimization method based on core scale simulation, and the method comprises the steps: selecting a real core sample of a target oil reservoir, carrying out the preprocessing of the real core sample, and constructing a three-dimensional digital core model of the target oil reservoir; selecting a surfactant according to reservoir characteristics of the target oil reservoir; according to the synergistic flooding characteristic and the oil-water two-phase flow characteristic of the surfactant in the pore medium of the target oil reservoir, a surfactant synergistic flooding model under the rock core scale is established; carrying out iterative solution on the synergistic flooding model through parallel calculation to realize dynamic simulation of the synergistic flooding process under the rock core scale, and outputting distribution data of a pressure field, a fluid saturation field and a surfactant concentration field in the three-dimensional digital rock core model; and according to the distribution data, determining a target parameter combination for synergistic flooding of the surfactant. The effect of improving the use degree of crude oil is achieved.

A liquid hydrogen storage tank capable of eliminating thermal stratification with low turbulence relates to the field of liquid hydrogen storage and comprises a tank body and a spray rod mechanism arranged in the tank body, the spray rod mechanism is communicated with a liquid hydrogen circulation pipeline, and liquid hydrogen in the tank body is extracted by the liquid hydrogen circulation pipeline and sprayed to a heat leakage point through the spray rod mechanism. The spray rod mechanism comprises a main guide pipe and a plurality of branch guide pipes, the tail ends of the branch guide pipes are provided with distribution assemblies attached to the heat leakage points, and the distribution assemblies are of structures defined by elastic metal wire meshes and filled with porous media, so that liquid hydrogen is dispersed and sprayed to the heat leakage points through the porous media, and turbulence of the liquid hydrogen is reduced. The spray rod mechanism is arranged in the storage tank, and the liquid hydrogen is directly sprayed to the heat leakage point by utilizing the guide pipe and the distribution component of the spray rod mechanism, so that turbulence of the liquid hydrogen in the tank is reduced, and evaporation of the liquid hydrogen caused by heat leakage is slowed down.

A representation of a rock capillary network is obtained and initial and boundary conditions of fluid flow and mineral precipitation process simulations for the rock capillary network are set. One or more instances of a geometry evolution simulation are performed, each geometry evolution simulation comprising obtaining fluid flow vectors for the rock capillary network, identifying one or more hotspots of nucleation in the rock capillary network, starting a mineral precipitation analysis and estimating a mineral accumulation over a given time interval for at least the identified hotspots of nucleation, adjusting a pore geometry to an effect of mineral precipitation for the rock capillary network, and iteratively repeating each of the one or more geometry evolution simulations until corresponding stop criteria are met for each geometry evolution simulation. A resulting rock under analysis property is computed from an aggregate of results of the one or more geometry evolution simulations.

The invention belongs to the technical field of grouting simulation, and particularly discloses a non-linear coupling simplified filling fracture flowing water grouting simulation method and system.The method comprises the steps that a geometric model of a to-be-simulated area is built, a fluid continuity equation and a momentum equation are built based on initialized model parameters, and a simulation result is obtained; the grouting pressure and the grouting speed of the current time step are calculated; a concentration field equation is constructed according to the velocity field of the current time step, and the slurry concentration distribution and the grouting velocity of the current time step are obtained through coupling solution based on the discrete concentration field equation and the momentum equation; a phase fraction equation is constructed according to the grouting speed of the current time step, and the slurry diffusion form in the water-rich filling fracture of the current time step is obtained; and repeating the process for each time step to finish the simulation of the flowing water grouting of the water-rich filling fracture. According to the method, the calculation efficiency and precision are considered while the algorithm is simplified, and accurate description of the slurry flow characteristics in the fractured porous medium is realized.

The invention discloses a rock unconventional reservoir carbon dioxide fracturing temperature field simulation method and system, and belongs to the technical field of oil and gas exploitation. Rock unconventional reservoir parameters and wellbore parameters are obtained, fluid physical property parameters of carbon dioxide fracturing fluid flowing in a wellbore are determined, and a multi-dimensional physical partition model is constructed; the unconventional reservoir is divided into a plurality of physical areas including a fluid flowing area, a static fluid area, a solid area and a porous medium area; thermal boundary conditions of all physical areas are coupled through an energy conservation equation, stratum elasticity modulus and Poisson's ratio are added to the thermal boundary conditions, a thermal-force coupling equation is constructed, carbon dioxide fracturing construction parameters obtained in real time are estimated, temperature field distribution nephograms of carbon dioxide fracturing fluid at different moments in the shaft flowing process are obtained, and the temperature field distribution nephograms of the carbon dioxide fracturing fluid at different moments are calculated. According to the method, the temperature distribution rule of different fracturing stages in the shaft-crack direction can be truly reflected.

The invention provides an impedance combined type broadband silencer based on a sound wave black hole gradient structure and a design method, and belongs to the technical field of noise control and environmental protection engineering, the whole impedance combined type broadband silencer is of an axisymmetric cylindrical structure, and the impedance combined type broadband silencer is composed of an inlet and outlet channel and a middle-section expanding type acoustic processing area; the expanded acoustic processing area comprises an inlet and outlet side expansion cavity, a composite impedance gradient perforation section and a porous sound absorption material layer. According to the sound wave black hole type multi-stage perforated ring structure, the sound wave black hole type multi-stage perforated ring structure composed of an axial uniform-parameter perforated ring belt and a radial gradient perforated ring belt is sequentially constructed in the silencer, so that the thickness of a perforated ring and the aperture and the perforation rate of the perforated ring belt are arranged on a propagation path according to a parameter gradient rule; porous materials are filled among the annular bands to form a gradient impedance composite dissipation system, so that sound waves are sequentially subjected to focusing and dissipation caused by geometric gradual shrinkage and viscosity and heat dissipation of porous media in the propagation process, and low-frequency enhanced absorption and wide-frequency-band continuous sound absorption are achieved.

The present disclosure provides a phase change energy storage concrete aggregate, a preparation method thereof and an application thereof, belonging to the technical field of building materials. The phase change energy storage concrete aggregate includes: a first inner core, the first inner core including composite phase change material particles and a porous cement-based material; and a first shell layer formed on the outer surface of the first inner core, the first shell layer including a cement-based encapsulating material; wherein, the composite phase change material particles include: a second inner core, the second inner core including an inorganic hydrated salt phase change material and a porous medium material, the inorganic hydrated salt phase change material being loaded in the pores of the porous medium material; and a second shell layer formed on the outer surface of the second inner core, the second shell layer sequentially including a hydrophobic layer, a polymer layer and a hydrophilic layer from inside to outside. The present disclosure effectively blocks the dehydration channels of the inorganic hydrated salt phase change material by using a double-shell layer structure, and improves the thermal performance of the phase change energy storage concrete aggregate.

The invention provides a semi-analytic LBM-DEM method for simulating particle-fluid two-phase flow, and the method comprises the steps: constructing a semi-analytic LBM-DEM coupling model, enabling the model to firstly determine the range of an expansion domain of particles, and obtaining the information, such as the average fluid velocity, the vorticity, the pressure gradient and the porosity, near the particles through traversing units in the expansion domain; and then, based on a theoretical formula and a semi-empirical formula, calculating the acting force of the fluid on the particles, and correcting a solid collision operator weight coefficient of a particle covering unit according to the acting force, so that synchronous evolution of particle dynamics and flow field distribution is realized. Compared with a classical analysis LBM-DEM coupling method, the method has the advantages that the calculation cost can be remarkably reduced under the condition that the calculation precision is guaranteed, and the method is particularly suitable for particle two-phase flow simulation in complex flow channels such as porous media and fractures.

The invention discloses a horizontal salt cavity circulating hydrogen storage and release whole process representation numerical simulation method which comprises the following steps: constructing an initial stratum model which comprises a mudstone upper layer, a rock salt interlayer and a mudstone lower layer; an ellipsoid is embedded in the initial stratum model, and a one-fourth stratum model with simplified calculation is obtained; adding a physical field module to the 1 / 4 stratum model to obtain an optimal stratum model; wherein the multi-physics field module comprises a solid mechanics physics field module, a Darcy law physics field module and a porous medium heat transfer physics field module; the optimal stratum model is subjected to grid division, the initial ground stress of the divided optimal stratum model is calculated firstly, then multi-field coupling data after the initial ground stress is added are calculated, and the multi-field coupling data comprise a temperature field, a stress field and a displacement field. The design capacity of the reservoir can be effectively increased, and the stable leakproofness of the reservoir is ensured by improving the structural form of the gas storage.