A method and system for identifying and repairing dead zones in a DPF porous medium model

Abstract

The present invention relates to a method and system for identifying and repairing dead zones in a DPF porous medium model, including: S1. Divide the pixel points in the two-dimensional porous medium model image into pore-phase nodes and solid-phase nodes, and construct a storage matrix to store the coordinates of all pore-phase nodes; S2. Select a pore-phase node, perform pore expansion on it, and obtain the total number of expanded nodes of the pore-phase node after the pore expansion. If the total number of expanded nodes exceeds a pre-set dead zone threshold, mark the expanded area of the pore-phase node as a detected pore-phase node. Otherwise, mark the pore-phase node and its expanded area as new solid-phase nodes; S3. Update the two-dimensional porous medium model and the storage matrix, and repeat step S2 until a pre-set termination condition is met. Compared with the prior art, the present invention identifies and repairs dead zones through pore expansion, can improve the problem of a large number of dead zones existing in the initial model, and thus can optimize the two-dimensional DPF porous medium model.

Description

Technical Field

[0001] The present invention relates to the field of optimizing the construction of DPF carrier models, and particularly to a method and system for identifying and repairing dead zones in a DPF porous medium model. Background Art

[0002] With the continuous update of emission regulations, the diesel engine pollutant emission control technology has also been continuously improved and upgraded. In order to meet the requirements of strict emission regulations, diesel particulate filters (DPFs) have been widely used in the diesel engine after-treatment emission control system and play an important role in the filtration and adsorption of diesel engine tail particulate matter. The structure of the DPF carrier determines the quality of the DPF filtration and regeneration performance. By constructing a DPF carrier model, it is possible to analyze and guide the development of DPFs with higher trapping efficiency and lower cost.

[0003] The wall-flow DPF is internally filled with fine channels parallel to the axis. The inlet channels and outlet channels are staggered and alternately blocked, forcing the exhaust gas containing mixed particulate matter emitted by the diesel engine to pass through the DPF porous medium layer. The effective trapping and adsorption process of particulate matter is completed through filtration mechanisms such as diffusion, interception, and gravitational sedimentation, thereby achieving the purification of particulate matter in the exhaust gas to meet the requirements of emission regulations.

[0004] The channel shape, size, and the internal structure and thickness of the porous medium of the DPF carrier play a decisive role in the fluidity of the DPF, and thus affect the economy and power performance of the engine. Through numerical simulation and experiments, only the influence of the change of its macroscopic parameters on the DPF performance can be analyzed, and the multi-phase flow coupling mechanism and related microscopic phenomena and parameters inside the DPF cannot be analyzed in detail. Most of the existing DPF research focuses on fields such as the construction and control of DPF regeneration models, carbon accumulation calculation, and macroscopic analysis of pressure drop. The construction of internal microscopic models of DPFs and flow analysis are relatively less, and it is impossible to accurately analyze the influence of the microscopic structure of the porous medium on the DPF performance.

[0005] In the prior art, Chinese Patent CN107035470A discloses an optimized flow field DPF regeneration system and control method. Active substances are generated by discharging through an NTP generator and sprayed out by a nozzle installed upstream of the DPF, entering the DPF to react with particulate matter to achieve regeneration. Real-time regeneration of the DPF is carried out under the operating state of the engine, effectively solving the problem of the decrease in NTP utilization rate caused by the large exhaust gas flow rate and high flow velocity of the engine. Chinese Patent CN109977469A proposes a method for constructing a two-dimensional porous medium model based on the Voronoi diagram. However, it can only realize channels with fixed internal dimensions, and the randomness of the carrier shape is insufficient, and it cannot be used to reflect the complex and disordered structure of the DPF porous medium layer, with a large difference from the actual situation.

[0006] Chinese Patent CN114547838A discloses a method for optimizing the two-phase boundary of a DPF porous medium model, proposes the concept of a boundary coefficient, and performs pixel cell conversion according to the boundary coefficient, thereby removing the burr-like boundary of the two-dimensional porous medium model, broadening the size of the average flow aperture, increasing the inherent permeability of the DPF carrier, improving the fluidity, and realizing the optimization of the two-phase boundary of the DPF porous medium model. However, in the technical solution of Patent CN114547838A, the burr-like boundary of the two-dimensional porous medium model is directly optimized, ignoring the existence of dead zones, that is, the fluid domains with relatively small areas in the two-dimensional porous medium model, such as the fluid domain containing N pixels enclosed by solid domain grids, have poor flow effects. Therefore, its optimization effect on the two-dimensional DPF porous medium model is not good. Summary of the Invention

[0007] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and provide a method and system for identifying and repairing dead zones in a DPF porous medium model.

[0008] The purpose of the present invention can be achieved through the following technical solutions:

[0009] A method for identifying and repairing dead zones in a DPF porous medium model includes the following steps:

[0010] S1. Read the two-dimensional porous medium model image, identify each pixel point in the two-dimensional porous medium model image, divide all pixel points into pore-phase nodes and solid-phase nodes, and construct a storage matrix to store the coordinates of all pore-phase nodes.

[0011] S2. Select a pore-phase node, perform pore expansion on it, and obtain the total number of expanded nodes of the pore-phase node after the pore expansion. If the total number of expanded nodes exceeds the preset dead zone threshold, mark the expanded area of the pore-phase node as a detected pore-phase node; otherwise, the pore-phase node and its expanded area are dead zones, and mark the pore-phase node and its expanded area as new solid-phase nodes.

[0012] S3. Update the two-dimensional porous medium model and the storage matrix, and repeat step S2 until the preset termination condition is met, completing the identification and repair of dead zones in the porous medium model.

[0013] Further, step S2 is specifically as follows:

[0014] S21. Select a pore-phase node P, use the pore-phase node P as the growth center, and initialize the number of expanded nodes Num to 0.

[0015] S22. Detect whether there are pore-phase nodes in the up, down, left, and right directions of the growth center. If there are, execute step S23; if not, the pore expansion ends, and execute step S24.

[0016] S23. Convert the pore-phase nodes in the up, down, left, and right directions of the growth center into new growth centers, use the new growth centers as expansion nodes, update the number of expansion nodes Num, and determine whether the number of expansion nodes Num exceeds the preset dead zone threshold. If it exceeds, the pore expansion ends and step S24 is executed; otherwise, step S22 is executed.

[0017] S24. If the number of expansion nodes Num exceeds the preset dead zone threshold, mark the pore-phase node and its expansion area as detected pore-phase nodes; otherwise, the pore-phase node and its expansion area are dead zones, and mark the pore-phase node and its expansion area as new solid-phase nodes.

[0018] Further, in step S21, select the pore-phase nodes in the order from left to right and from top to bottom in the two-dimensional porous medium model image.

[0019] Further, in step S3, update the two-dimensional porous medium model and the storage matrix based on the detected pore-phase nodes and new solid-phase nodes. Specifically:

[0020] Convert the pixel points marked as new solid-phase nodes in the two-dimensional porous medium model image into solid-phase nodes, and remove the pixel points corresponding to the detected pore-phase nodes and new solid-phase nodes from the storage matrix.

[0021] Further, in step S3, updating the two-dimensional porous medium model and the storage matrix is specifically:

[0022] Convert the pixel points marked as new solid-phase nodes in the two-dimensional porous medium model image into solid-phase nodes, read the two-dimensional porous medium model image, identify each pixel point in the two-dimensional porous medium model image, divide all pixel points into pore-phase nodes, solid-phase nodes, detected pore-phase nodes, and new solid-phase nodes, and construct a storage matrix to store the coordinates of all pore-phase nodes.

[0023] Further, the storage matrix stores the coordinates of all pore-phase nodes, and the coordinates of the pore-phase nodes are the row and column positions of the pixel points corresponding to the pore-phase nodes in the two-dimensional porous medium model image.

[0024] Further, the preset termination condition is that there are no pore-phase nodes in the storage matrix.

[0025] A DPF porous medium model dead zone identification and repair system includes:

[0026] A preprocessing module for reading a two-dimensional porous medium model image, identifying each pixel point in the two-dimensional porous medium model image, dividing all pixel points into pore-phase nodes and solid-phase nodes, and constructing a storage matrix to store the coordinates of all pore-phase nodes;

[0027] An identification module, which is used to select a pore-phase node, perform pore expansion on it, obtain the total number of expanded nodes of the pore-phase node after the pore expansion ends. If the total number of expanded nodes exceeds a preset dead zone threshold, mark the expansion area of the pore-phase node as a detected pore-phase node; otherwise, the pore-phase node and its expansion area are dead zones, and mark the pore-phase node and its expansion area as new solid-phase nodes.

[0028] An update module, which is used to update the two-dimensional porous medium model and the storage matrix.

[0029] A loop module, which is used to control the execution of the identification module and the update module according to preset termination conditions.

[0030] Furthermore, the identification module performs the following steps:

[0031] A1. Select a pore-phase node P, use the pore-phase node P as the growth center, and initialize the number of expanded nodes Num to 0.

[0032] A2. Detect whether there are pore-phase nodes in the up, down, left, and right directions of the growth center. If there are, execute step A3; if not, the pore expansion ends, and execute step A4.

[0033] A3. Convert the pore-phase nodes in the up, down, left, and right directions of the growth center into new growth centers, use the new growth centers as expanded nodes, update the number of expanded nodes Num, and determine whether the number of expanded nodes Num exceeds the preset dead zone threshold. If it exceeds, the pore expansion ends, and execute step A4; otherwise, execute step A2.

[0034] A4. If the number of expanded nodes Num exceeds the preset dead zone threshold, mark the pore-phase node and its expansion area as a detected pore-phase node; otherwise, the pore-phase node and its expansion area are dead zones, and mark the pore-phase node and its expansion area as new solid-phase nodes.

[0035] Furthermore, in step A1, select the pore-phase nodes in the order from left to right and from top to bottom in the two-dimensional porous medium model image.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] The present invention identifies dead zones through pore expansion and repairs and fills the dead zones into solid-phase regions, which can improve the problem of a large number of dead zones in the initial model, thereby optimizing the two-dimensional DPF porous medium model, providing a basis for subsequent optimization of the burr boundary of the porous medium, and providing a theoretical support for the structural optimization of the DPF carrier. Description of the Drawings

[0038] Figure 1Flow chart of the present invention;

[0039] Figure 2 Two-dimensional porous medium diagram generated by QSGS;

[0040] Figure 3 Schematic diagram of the expansion of the pore phase over time steps under ideal conditions;

[0041] Figure 4 Schematic diagram of the expansion of the pore phase over time steps under actual conditions;

[0042] Figure 5 Schematic diagram of the identification and repair effect of the dead zone in the porous medium model Detailed implementation mode

[0043] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. This embodiment is implemented on the premise of the technical solution of the present invention, and the detailed implementation mode and specific operation process are given, but the protection scope of the present invention is not limited to the following embodiments.

[0044] Embodiment 1:

[0045] A method for identifying and repairing the dead zone of a DPF porous medium model, as Figure 1 shown, includes the following steps:

[0046] S1. Read the two-dimensional porous medium model image, identify each pixel point in the two-dimensional porous medium model image, divide all pixel points into pore phase nodes and solid phase nodes, and construct a storage matrix to store the coordinates of all pore phase nodes;

[0047] Among them, the storage matrix stores the coordinates of all pore phase nodes, and the coordinates of the pore phase nodes are the row and column positions of the pixel points corresponding to the pore phase nodes in the two-dimensional porous medium model image. For example, the storage matrix can be set as a matrix with n rows and 2 columns, where n is the total number of pore phase nodes in the two-dimensional porous medium model image. The first column of the storage matrix stores the abscissa of each pore phase node, and the second column of the storage matrix stores the ordinate of each pore phase node.

[0048] S2. Select a pore phase node, perform pore expansion on it, and obtain the total number of expanded nodes of the pore phase node after the pore expansion. If the total number of expanded nodes exceeds the preset dead zone threshold, mark the expansion area of the pore phase node as the detected pore phase node; otherwise, the pore phase node and its expansion area are the dead zone, and mark the pore phase node and its expansion area as new solid phase nodes;

[0049] Step S2 is specifically:

[0050] S21. Select a pore phase node P, use the pore phase node P as the growth center, and initialize the number of expanded nodes Num to 0;

[0051] Here, pore-phase nodes are selected in the order from left to right and from top to bottom in the two-dimensional porous medium model image. That is, each time a pore-phase node is selected, the first row of the two-dimensional porous medium model image is selected first, and then traversed from left to right in turn until a pore-phase node is found. If there is no pore-phase node in the first row, the second row of the two-dimensional porous medium model image is selected, and then the above steps are repeated. Of course, in other embodiments, the pore-phase nodes can also be selected in the order from top to bottom and from left to right, or other personalized selection orders.

[0052] S22. Detect whether there are pore-phase nodes in the up, down, left, and right directions of the growth center. If so, execute step S23; if not, the pore expansion ends, and execute step S24.

[0053] S23. Convert the pore-phase nodes in the up, down, left, and right directions of the growth center into new growth centers, use the new growth centers as expansion nodes, update the number of expansion nodes Num, and determine whether the number of expansion nodes Num exceeds the preset dead zone threshold. If it exceeds, the pore expansion ends, and execute step S24; otherwise, execute step S22.

[0054] Among them, it can be understood that the dead zone threshold is related to the identification of the dead zone and can be set according to actual needs and experience, such as set to 80, 200, etc.

[0055] S24. If the number of expansion nodes Num exceeds the preset dead zone threshold, mark the pore-phase node and its expansion area as the detected pore-phase node; otherwise, the pore-phase node and its expansion area are the dead zone, and mark the pore-phase node and its expansion area as the new solid-phase node.

[0056] S3. Update the two-dimensional porous medium model and the storage matrix, and repeat step S2 until the preset termination condition is met, and complete the dead zone identification and repair of the porous medium model.

[0057] In step S3, convert the pixel points marked as new solid-phase nodes in the two-dimensional porous medium model image into solid-phase nodes. The pixel points corresponding to the detected pore-phase nodes and the new solid-phase nodes can be removed from the storage matrix to update the storage matrix. Of course, the two-dimensional porous medium model image can also be read again, each pixel point in the two-dimensional porous medium model image is identified, and all pixel points are divided into pore-phase nodes, solid-phase nodes, detected pore-phase nodes, and new solid-phase nodes, and a new storage matrix is constructed to store the coordinates of all pore-phase nodes.

[0058] In step S3, the preset termination condition can be that there are no pore-phase nodes in the storage matrix, or other thresholds set according to experience, such as the total number of new solid-phase nodes is greater than the preset threshold, etc.

[0059] As Figure 2 shown, it is a two-dimensional porous medium image randomly generated by QSGS, and this image can be binarized. The process is similar to the finite element idea. Any element of a two-dimensional porous medium model can be decomposed into tiny square pixel cells. The solid domain (solid-phase nodes) is represented by white grids, while the black grids represent the fluid domain (pore-phase nodes). The size of the computational domain of the two-dimensional porous medium model can be determined based on the two-dimensional porous medium image, and coordinates in the horizontal x-direction and vertical y-direction can be established. Thus, the coordinates of each pixel cell will be uniquely determined.

[0060] In this embodiment, in the two-dimensional porous medium image, the solid domain (i.e., the solid-phase nodes, which are the white cells in the figure) in the binarized picture is represented by 1, and the fluid domain (i.e., the fluid-domain nodes, which are the black cells in the figure) is represented by 0. The program can Figure 2 perform row-column scanning on the binarized picture shown and identify the pore-phase nodes, and construct an n-row 2-column adaptive storage matrix to store the coordinates of the pore-phase nodes. The n rows of the storage matrix represent the total number of pore-phase nodes. The first column stores the abscissa of the pore-phase nodes, and the second column stores the ordinate of the pore-phase nodes.

[0061] For the convenience of subsequent traversal, the coordinates of the pore-phase nodes are stored in the storage matrix in the order from top to bottom and from left to right.

[0062] Select a pore-phase node P, and perform pore expansion in the binarized image as follows: within T = 1 time step, with the pore-phase node P as the growth center, detect whether there are pore-phase nodes around the growth center (in the four directions of up, down, left, and right), that is, determine whether there are pixel cells with a value of 0 around the pore-phase node P. If there are, then within T = 2 time step, the pore-phase nodes around the pore-phase node P will be changed into new growth centers. If not, it means that the detection of the pore-phase region of the pore-phase node P is completed.

[0063] Within T = 3 time step, for each new growth center, detect whether there are pore-phase nodes around the growth center (in the four directions of up, down, left, and right), that is, determine whether there are pixel cells with a value of 0 around the growth center. If there are, then within T = 4 time step, the pore-phase nodes around the growth center will be changed into new growth centers. If not, it means that the detection of the pore-phase region of the pore-phase node P is completed.

[0064] ……Repeat the above process until there are no pore-phase nodes around each growth center, or the number of pore-phase nodes that have been detected and transformed into growth centers (i.e., the number of expanding nodes) exceeds the dead zone threshold, then stop. Ideally, if there are pore-phase nodes in the four directions of up, down, left, and right around the growth center, its pore expansion is as Figure 3 shown. In actual situations, there are also solid-phase nodes in the four directions of up, down, left, and right around the growth center. Therefore, its pore expansion is as Figure 4 shown.

[0065] After the pore expansion ends, if the number of expanding nodes Num exceeds the preset dead zone threshold, it is determined as a non-dead zone. Then, mark the pore-phase node and its expansion area as the detected pore-phase node, and use the value 3 to replace the value 0 of the pore-phase node and its expansion area. The purpose of this step is to mark the identified pore area to prevent repeated detection; if the number of expanding nodes Num does not exceed the preset dead zone threshold, it is determined as a dead zone, and use the value 2 to replace the value 0 of the pore-phase node and its expansion area. The purpose of this step is to facilitate the distinction from the initial pore-phase nodes and initial solid-phase nodes.

[0066] The final effect of the program running is as Figure 5 shown. The gray area represents the dead zone (i.e., the solid-phase node area transformed from new solid-phase nodes), the white is the solid-phase area, and the black is the pore-phase area. The present invention identifies the dead zone through pore expansion and repairs and fills the dead zone into the solid-phase area, which can improve the problem of a large number of dead zones existing in the initial model. Thus, it can optimize the two-dimensional DPF porous medium model, provide a basis for the subsequent optimization of the burr boundary of the porous medium, and provide theoretical support for the structural optimization of the DPF carrier.

[0067] Of course, the result of the dead zone repair process in this application is to increase the number of solid-phase nodes, which will reduce the porosity of the model. To maintain the porosity unchanged and achieve the purpose of optimizing the flow domain, it is necessary to cooperate with Patent CN114547838A to optimize the burr boundary of the porous medium of the model, and finally realize the optimization of the two-dimensional porous medium flow domain, improve the accuracy of the model, increase the credibility of the simulation modeling, and thus provide theoretical guidance for the improvement of the DPF performance.

[0068] This application also provides a DPF porous medium model dead zone identification and repair system, including:

[0069] A preprocessing module for reading the two-dimensional porous medium model image, identifying each pixel point in the two-dimensional porous medium model image, classifying all pixel points into pore-phase nodes and solid-phase nodes, and constructing a storage matrix to store the coordinates of all pore-phase nodes;

[0070] An identification module, configured to select a pore-phase node, perform pore expansion on it, and obtain the total number of expanded nodes of the pore-phase node after the pore expansion ends. If the total number of expanded nodes exceeds a preset dead zone threshold, mark the expansion area of the pore-phase node as a detected pore-phase node; otherwise, the pore-phase node and its expansion area are dead zones, and mark the pore-phase node and its expansion area as new solid-phase nodes;

[0071] An update module, configured to update the two-dimensional porous medium model and the storage matrix;

[0072] A loop module, configured to control the execution of the identification module and the update module according to preset termination conditions.

[0073] The working processes and manners of the various modules in the above DPF porous medium model dead zone identification and repair system are the same as those described in the DPF porous medium model dead zone identification and repair method above, and will not be elaborated here.

[0074] The preferred specific embodiments of the present invention have been described in detail above. It should be understood that those of ordinary skill in the art can make many modifications and variations based on the concept of the present invention without creative efforts. Therefore, all technical solutions that can be obtained by those skilled in the art in the technical field of the present invention through logical analysis, reasoning, or limited experiments based on the concept of the present invention on the basis of the prior art shall fall within the protection scope determined by the claims.

Claims

1. A method for identifying and repairing dead zones in a DPF porous medium model, characterized in that It includes the following steps: S1. Read the two-dimensional porous medium model image, identify each pixel point in the two-dimensional porous medium model image, divide all pixel points into pore-phase nodes and solid-phase nodes, and construct a storage matrix to store the coordinates of all pore-phase nodes; S2. Select a pore-phase node, perform pore expansion on it, and obtain the total number of expanded nodes of the pore-phase node after the pore expansion. If the total number of expanded nodes exceeds the preset dead zone threshold, mark the expanded area of the pore-phase node as a detected pore-phase node; otherwise, the pore-phase node and its expanded area are dead zones, and mark the pore-phase node and its expanded area as new solid-phase nodes; S3. Update the two-dimensional porous medium model and the storage matrix, repeat step S2 until the preset termination condition is met, and complete the dead zone identification and repair of the porous medium model; Step S2 is specifically as follows: S21. Select a pore-phase node P, take the pore-phase node P as the growth center, and initialize the number of expanded nodes Num to 0; S22. Detect whether there are pore-phase nodes in the up, down, left, and right directions of the growth center. If there are, execute step S23; if not, the pore expansion ends, and execute step S24; S23. Convert the pore-phase nodes in the up, down, left, and right directions of the growth center into new growth centers, take the new growth centers as expanded nodes, update the number of expanded nodes Num, and determine whether the number of expanded nodes Num exceeds the preset dead zone threshold. If it exceeds, the pore expansion ends, and execute step S24; otherwise, execute step S22; S24. If the number of expanded nodes Num exceeds the preset dead zone threshold, mark the pore-phase node and its expanded area as a detected pore-phase node; otherwise, the pore-phase node and its expanded area are dead zones, and mark the pore-phase node and its expanded area as new solid-phase nodes; In step S3, the update of the two-dimensional porous medium model and the storage matrix is specifically as follows: Convert the pixel points marked as new solid-phase nodes in the two-dimensional porous medium model image into solid-phase nodes, read the two-dimensional porous medium model image, identify each pixel point in the two-dimensional porous medium model image, divide all pixel points into pore-phase nodes, solid-phase nodes, detected pore-phase nodes, and new solid-phase nodes, and construct a storage matrix to store the coordinates of all pore-phase nodes.

2. A method for identifying and repairing dead zones in a DPF porous medium model according to claim 1, characterized in that, In step S21, the pore-phase nodes are selected in the order from left to right and from top to bottom in the two-dimensional porous medium model image.

3. A method for identifying and repairing dead zones in a DPF porous medium model according to claim 1, characterized in that, The storage matrix stores the coordinates of all pore-phase nodes, and the coordinates of the pore-phase nodes are the row and column positions of the pixel points corresponding to the pore-phase nodes in the two-dimensional porous medium model image.

4. A method for identifying and repairing dead zones in a DPF porous medium model according to claim 1, characterized in that, The preset termination condition is that there are no pore-phase nodes in the storage matrix.

5. A DPF porous medium model dead zone identification and repair system, characterized in that, It includes: A preprocessing module for reading the two-dimensional porous medium model image, identifying each pixel point in the two-dimensional porous medium model image, dividing all pixel points into pore-phase nodes and solid-phase nodes, and constructing a storage matrix to store the coordinates of all pore-phase nodes; An identification module, which is used to select a pore-phase node, perform pore expansion on it, and obtain the total number of expanded nodes of the pore-phase node after the pore expansion ends. If the total number of expanded nodes exceeds the preset dead zone threshold, the expanded area of the pore-phase node is marked as a detected pore-phase node; otherwise, the pore-phase node and its expanded area are dead zones, and the pore-phase node and its expanded area are marked as new solid-phase nodes. An update module, which is used to update the two-dimensional porous medium model and the storage matrix. A loop module, which is used to control the execution of the identification module and the update module according to the preset termination conditions. The identification module performs the following steps: A1. Select a pore-phase node P, use the pore-phase node P as the growth center, and initialize the number of expanded nodes Num to 0. A2. Detect whether there are pore-phase nodes in the up, down, left, and right directions of the growth center. If there are, execute step A3; if not, the pore expansion ends, and execute step A4. A3. Convert the pore-phase nodes in the up, down, left, and right directions of the growth center into new growth centers, use the new growth centers as expanded nodes, update the number of expanded nodes Num, and determine whether the number of expanded nodes Num exceeds the preset dead zone threshold. If it exceeds, the pore expansion ends, and execute step A4; otherwise, execute step A2. A4. If the number of expanded nodes Num exceeds the preset dead zone threshold, mark the pore-phase node and its expanded area as detected pore-phase nodes; otherwise, the pore-phase node and its expanded area are dead zones, and mark the pore-phase node and its expanded area as new solid-phase nodes. Updating the two-dimensional porous medium model and the storage matrix specifically includes: Converting the pixel points marked as new solid-phase nodes in the two-dimensional porous medium model image into solid-phase nodes, reading the two-dimensional porous medium model image, identifying each pixel point in the two-dimensional porous medium model image, classifying all pixel points into pore-phase nodes, solid-phase nodes, detected pore-phase nodes, and new solid-phase nodes, and constructing a storage matrix to store the coordinates of all pore-phase nodes.

6. The DPF porous medium model dead zone identification and repair system according to claim 5, characterized in that In step A1, the pore-phase nodes are selected in the order from left to right and from top to bottom in the two-dimensional porous medium model image.

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