1447 results about "Porous medium" patented technology

The present invention discloses a two-phase numerical simulation method for a microchannel heat exchanger, and the method includes: simplifying a real heat exchange channel into a porous medium model. Governing equations are determined according to two-phase flow and heat transfer characteristics thereof, and the equations are solved iteratively until results converge to complete numerical simulation. The present invention is beneficial to promoting optimization design of two-phase flow microchannel heat exchangers.

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 discloses a polyurethane permeation grouting diffusion simulation method, device and equipment and a medium, and the method comprises the steps: building a geometric model of permeation grouting diffusion of polyurethane in a to-be-injected porous medium according to the physical attribute data of the to-be-injected porous medium; establishing a physical field of the geometric model by adopting a Richardz equation and a porous medium dilute material transfer equation, and adjusting the geometric model according to material attribute parameters of the geometric model obtained by the physical field; setting a boundary condition and an initial value of the adjusted geometric model, and performing grid division on the adjusted geometric model based on a local refinement method to obtain a permeation grouting diffusion simulation model; and solving the permeation grouting diffusion simulation model according to the transient solver, and completing simulation of permeation grouting diffusion of polyurethane in the porous medium. According to the method provided by the invention, the modeling accuracy of the slurry diffusion process is improved.

A method for separating liquid-like (T2e) from solid-like (T2G) 1H NMR transverse relaxation times in porous media uses novel pulse sequences together with a 1H NMR spectrometer optimized for geological core samples. The method is applied to obtain 1D T2 distributions and 2D T1-T2 maps in organic-rich chalks for quantification of liquid-like signal (micropore fluids, meso-macropore fluids, fluids dissolved in organic matter, and clay-bound water) and solid-like signal (kerogen, bitumen, and clay hydroxyls). The novel pulse sequences comprise a solid-echo, which detects more solid-like signal than an FID. The method is used for fluid typing in micro / meso-macro pores, clay mineral identification, determination of kerogen content, and quantification of solvent-extracted bitumen versus bitumen expelled from kerogen due to swelling from dissolved hydrocarbons. The method is used to quantify the asphaltene, resin, aromatic, and / or saturate content of bitumen in the rock.

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 relates to a method for optimizing a liquid metal micro-channel radiator. The method comprises the following steps: determining basic parameters for optimizing the radiator; determining boundary conditions of a micro-channel inlet, and establishing a two-dimensional liquid metal micro-channel radiator model; establishing a topological optimization objective function and constraint conditions according to thermal control index requirements; carrying out material interpolation function definition on the reverse permeability coefficient of the porous medium, the heat conduction coefficient of the material and the specific heat coefficient of the material; carrying out iterative calculation on the two-dimensional liquid metal micro-channel radiator model to obtain an optimized radiator channel configuration; constructing a three-dimensional model of the liquid metal radiator flow channel; comparing an analysis result of the three-dimensional finite element model of the radiator with a heat dissipation index and a flow index, and judging whether a working requirement is met or not; and when the working requirements are met, the liquid metal micro-channel radiator with the most effective corresponding heat dissipation capability is obtained. According to the invention, the power consumption of an external driving system can be reduced, and the corresponding optimal liquid metal micro-channel radiator structure can be obtained.

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 ecological restoration, in particular to a cylindrical permeation grouting range determining method and system considering the tortuosity of a porous medium, and the method comprises the following steps: collecting porous medium characteristic data and underground water pressure at a selected grouting point position; meanwhile, Bingham cement grout characteristic data are collected, and grouting parameters are set; the tortuosity of the porous medium is considered, and then the seepage velocity of Bingham cement grout is determined based on a rheological equation of Bingham fluid and a mechanical analysis equation of an infinitesimal body in the grouting pipe; and under the condition of the cylindrical diffusion boundary, a cylindrical permeation grouting range solving model is constructed based on the seepage velocity and the unit time grouting amount calculation formula, and the cylindrical permeation grouting spatial diffusion range quantitative index is solved according to the grouting parameters so as to determine the cylindrical permeation grouting range. The grouting quality and reliability in the ecological restoration project can be improved, the construction requirement under the complex ecological engineering environment is met, and effective restoration and sustainable development of an ecological system are achieved.

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.

A system and method for measuring physical property parameters of a fluid in a porous medium. The system for measuring physical property parameters of a fluid in a porous medium comprises: a core device (A), which comprises at least two first-type core modules (A1) and second-type core modules (A2) located between the at least two first-type core modules (A1); an injection device (B); a confining pressure device (C); and a control device (D), which is used for controlling the opening or closing state of a conduit between adjacent core modules, wherein the control device (D) is further configured to calibrate the pore volume of each core on the basis of a balance pressure of when an experimental gas injected into the core device (A) sequentially passes through the core modules (A1, A2), and to record, when a fluid sample injected into the core device (A) saturates the first first-type core module (A1), a balance pressure of when the fluid sample sequentially diffuses to the core modules (A1, A2), thus obtaining physical property parameters of the fluid sample on the basis of the pore volume and the balance pressure.

A core holder assembly (100) for holding a test sample (200) including a consolidated porous medium includes an outer barrel including a central passage defined by an inner surface, a confining solid positioned in the central passage of the outer barrel, wherein the confining solid includes an outer surface sealed against the inner surface of the outer barrel and an inner surface, wherein the confining solid includes a rigid, lead-free material, and the test sample positioned within the confining solid, wherein the inner surface of the confining solid is sealed against an outer surface of the test sample.

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 provides a method for evaluating the permeation enhancing effect of ultrasonic wave acting on a porous medium, which comprises the following steps: carrying out first NMR test on a dried, vacuumized and saturated sample to obtain a first saturated water T2 spectrum of the sample, and analyzing related parameters of the sample through the first saturated water T2 spectrum; performing a first ultrasonic permeation enhancing effect on the sample subjected to the first NMR test through ultrasonic waves, and performing a second NMR test on the sample every set time in the process to obtain a second saturated water T2 spectrum; after each second NMR test is finished, the sample is vacuumized again for water saturation, and the sample which is vacuumized again for water saturation is subjected to a third NMR test to obtain a third water saturation T2 spectrum; related parameters of the medium after the ultrasonic action at different time points are calculated through the third water saturation T2 spectrum, and the intensity of the ultrasonic cavitation effect is calculated according to the second water saturation T2 spectrum and the third water saturation T2 spectrum; and evaluating the permeation enhancing effect of the ultrasonic waves through the previous and later related parameters. According to the method, the ultrasonic cavitation intensity and the permeation increasing effect can be evaluated at the same time.

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 an efficient and high-precision numerical simulation method for an air cooling field of a diesel engine. The method comprises the following steps: (1) based on a porous medium model theory, using a defined porous medium model to replace an internal structure of an original radiator to establish a three-dimensional radiator simplified model containing a porous medium area; (2) according to the dimensionless similarity of speed distribution of a fan rotational flow main body section, the dissipation rate generation and diffusion term coefficient of a turbulent energy dissipation equation in a standard k-epsilon turbulence model are adjusted, (3) the standard k-epsilon turbulence model is adopted for a forced convection dominant area, the k-epsilon turbulence model corrected by the turbulent flow viscosity coefficient is adopted for a natural convection dominant area, and the turbulent flow viscosity coefficient of the natural convection dominant area is corrected. In order to guarantee smooth and stable transition of turbulence viscosity, a k-epsilon turbulence model corrected by turbulence viscosity coefficient linear interpolation is adopted for a transition area of forced convection and natural convection; and (4) a diesel engine air cooling field numerical simulation technology based on partition processing is adopted. According to the method, high-precision numerical simulation on the basis of a small number of grids is realized.

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.