Porous linkage coupling-based coal seam gas extraction effective radius dynamic evaluation system

Abstract

The present application provides a coal seam gas extraction effective radius dynamic evaluation system based on porous linkage coupling, relates to the field of coal mine safety engineering and physical analysis technology, and through synchronous collection and standardized processing of multiple source parameters such as extraction orifice negative pressure, gas flow, gas concentration, extraction response time delay, coal seam original gas pressure and hole space information, the present application constructs extraction action impedance coefficient, porous linkage coupling coefficient and dynamic effective radius correction coefficient, and compares and evaluates with corresponding threshold value respectively. When the evaluation result is abnormal, the adaptive regulation and control strategy of negative pressure, time sequence and proportion of single-hole and multi-hole collaborative extraction is triggered, and after adjustment, re-evaluation is carried out, the dynamic correction and closed-loop optimization of extraction effective radius are realized, and the accuracy of coal seam gas extraction range evaluation and the safety and stability of extraction system operation are improved.

Description

Technical Field

[0001] This invention relates to the field of coal mine safety engineering and physical analysis technology, specifically to a dynamic evaluation system for the effective radius of coal seam gas extraction based on multi-pore linkage coupling. Background Technology

[0002] Coal seam gas drainage is a key technical means in coal mine safety production. Its core objective is to effectively release and migrate gas in the coal seam by drilling drainage holes and applying negative pressure, thereby reducing gas content and pressure and preventing gas accidents. In practical engineering applications, the effective drainage radius, as an important indicator for measuring the range of action of a single drainage hole or drainage system, is directly related to the density of drainage hole layout, the setting of drainage parameters, and the regional gas control effect.

[0003] Current methods for determining the effective radius of coal seam gas drainage mainly rely on engineering experience, empirical formulas, or local monitoring results for estimation. They typically use negative pressure attenuation or gas flow rate changes from a single-hole perspective. This approach struggles to quantitatively describe the dynamic changes during drainage and lacks effective characterization of coal seam heterogeneity, gas occurrence differences, and the disturbance response during drainage, leading to significant uncertainty in the assessment results of the effective drainage radius.

[0004] On the other hand, in actual drainage projects, drainage holes are often arranged in multi-hole groups. Different drainage holes are interconnected through the coal seam fracture network and pore structure. Their drainage effects are not independent but exhibit a significant linkage and coupling effect. However, existing technologies mainly focus on single-hole parameter analysis and lack a systematic quantitative method for the inter-hole coupling relationship under multi-hole linkage drainage conditions, making it difficult to reflect the impact of multi-hole synergy on the effective drainage radius.

[0005] Furthermore, with the development of downhole sensor technology and monitoring systems, operational data such as negative pressure at the extraction orifice, gas flow rate, and gas concentration can be continuously collected. However, the utilization rate of the above-mentioned multi-source monitoring data is generally low in the existing technology. It is often used only for single indicator monitoring or post-event analysis. There is a lack of technical means to uniformly process and jointly analyze multi-source data and serve the dynamic evaluation of the effective extraction radius.

[0006] Meanwhile, coal seams generally exhibit significant spatial heterogeneity, with substantial differences in permeability, fracture development, and gas release response across different regions. Existing effective radius assessment methods struggle to integrate these spatial differences with real-time response characteristics during the extraction process, resulting in assessment results that fail to accurately reflect actual extraction effectiveness.

[0007] Furthermore, the evaluation results of the effective extraction radius in existing technologies mostly remain at the analysis level, lacking effective linkage with decision-making processes such as extraction parameter adjustment and inter-well collaborative optimization. This makes it difficult to form a closed-loop control mechanism of "monitoring-evaluation-adjustment," which is not conducive to the dynamic optimization operation of the extraction system. Summary of the Invention

[0008] The purpose of this invention is to provide a dynamic evaluation system for the effective radius of coal seam gas extraction based on multi-pore linkage coupling, so as to solve the problems mentioned in the background art.

[0009] To achieve the above objectives, the present invention provides the following technical solution:

[0010] A dynamic evaluation system for the effective radius of coal seam gas drainage based on multi-pore linkage coupling includes:

[0011] The data acquisition module is configured to synchronously acquire multiple physical parameters related to the extraction range during the coal seam gas multi-hole extraction process, and obtain raw data of negative pressure at the extraction orifice, raw data of gas flow rate, raw data of gas concentration, extraction response time delay data, and raw coal seam gas pressure data and spatial coordinate information of the extraction orifice.

[0012] The data processing module is configured to perform unified timestamp alignment, outlier identification and removal on the collected data, and establish a standard dataset.

[0013] The extraction impedance assessment module is configured to obtain the average negative pressure value of the extraction orifice and the gas flow rate attenuation rate based on a standard dataset, calculate the extraction impedance coefficient, and compare it with the preset extraction impedance threshold. When the extraction impedance exceeds the threshold, an enhanced adjustment strategy for the single-orifice extraction negative pressure and extraction duration is triggered.

[0014] The multi-hole linkage coupling analysis module is configured to calculate the multi-hole linkage coupling coefficient based on the average extraction negative pressure difference, gas concentration change rate difference, and spatial distance between adjacent extraction holes, and compare it with the preset multi-hole linkage coupling threshold. When the linkage coupling between holes is insufficient, a coordinated adjustment strategy for the start-stop sequence between holes, extraction negative pressure gradient, and hole spacing configuration is triggered, and a set of effective input parameters is generated.

[0015] The dynamic effective radius evaluation module is configured to construct a dynamic effective radius correction coefficient by acquiring the average value of the multi-hole linkage coupling coefficient and the spatial partition index, and compare it with the preset dynamic effective radius correction threshold. When the evaluation result is unqualified, the linkage control strategy for adjusting the extraction negative pressure, adjusting the inter-hole collaborative extraction ratio, and dynamically correcting the extraction timing is triggered. After adjustment, the calculation is recalculated to form a closed-loop evaluation and optimization mechanism.

[0016] Furthermore, the data acquisition module includes a negative pressure extraction flow acquisition unit, a gas concentration response time acquisition unit, and a coal seam original state spatial information acquisition unit;

[0017] The negative pressure extraction flow acquisition unit is used to monitor the changes in extraction intensity of each extraction hole in real time under the multi-hole extraction condition of coal seam gas; by installing a negative pressure sensor at the opening of each extraction hole, the original value of negative pressure at the extraction hole opening is acquired in real time; by installing a gas flow meter on the extraction pipeline of each extraction hole, the original value of extraction gas flow is acquired in real time.

[0018] The gas concentration response time acquisition unit is used to monitor the gas release response characteristics in real time during coal seam gas extraction. By installing a gas concentration sensor at the outlet of the extraction hole or the end of the extraction pipeline, the raw value of the extracted gas concentration is acquired in real time. The extraction response time delay value is obtained by synchronously recording the time of negative pressure change at the extraction hole and the time when the gas concentration or extraction flow rate changes significantly.

[0019] The original state spatial information acquisition unit of the coal seam is used to monitor the basic occurrence conditions of the coal seam in the extraction area in real time; the original gas pressure of the coal seam is obtained by conducting gas pressure tests at borehole test locations or historical exploration points, or by calling historical geological measurement data; and the spatial coordinate information of the extraction holes is obtained by measuring the location of each extraction hole through the downhole measurement system.

[0020] Furthermore, the data processing module is used to perform time synchronization processing on the time series data of the original values ​​of the negative pressure at the extraction orifice, the original values ​​of the extracted gas flow rate, and the original values ​​of the extracted gas concentration using a unified timestamp alignment method; then, it uses outlier identification and removal methods to filter out abrupt changes in data caused by instantaneous sensor interference and communication anomalies; and establishes a standard dataset.

[0021] Furthermore, the extraction impedance assessment module includes a single-hole extraction intensity parameter extraction unit, a first calculation unit, and a first analysis unit;

[0022] The single-hole extraction intensity parameter extraction unit is used to extract the original negative pressure value of the i-th extraction hole in the standard dataset, and obtain the average negative pressure value of the hole during the stable extraction stage by using an arithmetic average algorithm; it also extracts the original value of the gas flow rate of the i-th extraction hole, and processes the change of the gas flow rate over time by using a unit time change rate calculation method; and obtains the gas flow rate decay rate per unit time by calculating the flow rate difference between adjacent time points and the corresponding time interval.

[0023] The first calculation unit is used to calculate the extraction resistance coefficient by combining the average negative pressure value of the orifice during the stable extraction stage and the gas flow attenuation rate of the i-th extraction orifice, along with the original gas pressure of the coal seam and the extraction response time delay value of the i-th extraction orifice, after dimensionless processing, using a weighted linear synthesis algorithm.

[0024] Furthermore, the first analysis unit is used to obtain a first evaluation result by comparing the sampling impedance coefficient with the sampling impedance threshold through a preset sampling impedance threshold, including:

[0025] When the extraction impedance coefficient is less than or equal to the extraction impedance threshold, it indicates that the current extraction impedance of the extraction hole is within a controllable range and should be continuously monitored.

[0026] When the extraction impedance coefficient exceeds the extraction impedance threshold, it indicates that the extraction impedance of the current extraction hole exceeds the controllable range. This poses a risk of insufficient effective action of the extraction negative pressure on the coal body, mismatch between the gas release rate and extraction intensity, or limited extraction influence range. This triggers the first warning instruction and generates the first strategy: implement a single-hole enhanced extraction strategy for the current extraction hole, increase the extraction negative pressure parameter of the corresponding extraction hole by 5% to 15% incrementally, and extend the extraction duration by 10% to 20%. After adjustment, recalculate until the extraction impedance coefficient is less than or equal to the extraction impedance threshold.

[0027] Furthermore, the multi-pore linkage coupling analysis module includes a pore coupling feature parameter extraction unit, a second calculation unit, and a second analysis unit;

[0028] The inter-hole coupling feature parameter extraction unit is used to extract the original negative pressure value of the i-th extraction hole and the original negative pressure value of the adjacent j-th extraction hole from the standard dataset; use an arithmetic average algorithm to obtain the average extraction negative pressure value of the adjacent i-th extraction hole and the average extraction negative pressure value of the j-th extraction hole within a preset time window; extract the original gas concentration values ​​of the i-th and j-th extraction holes from the standard dataset, use a time gradient calculation method to process the gas concentration change trend over time, and obtain the gas concentration change rate of the i-th and j-th extraction holes over time by calculating the ratio of the gas concentration change at adjacent sampling times to the time interval; and use a spatial distance inverse ratio calculation method based on the spatial coordinate information of the extraction holes to obtain the spatial distance between the i-th and j-th extraction holes.

[0029] Furthermore, the second calculation unit is used to calculate the multi-hole linkage coupling coefficient by acquiring the average negative pressure value of the adjacent i-th extraction hole and the average negative pressure value of the j-th extraction hole within the preset time window, the rate of change of gas concentration of the i-th extraction hole with time and the rate of change of gas concentration of the j-th extraction hole with time, and combining the spatial distance between the i-th and j-th extraction holes and the original gas pressure of the coal seam, after dimensionless processing.

[0030] Furthermore, the second analysis unit is used to obtain a second evaluation result by comparing the multi-pore linkage coupling coefficient with the preset multi-pore linkage coupling threshold through a comparative analysis, including:

[0031] When the multi-hole linkage coupling coefficient is greater than or equal to the multi-hole linkage coupling threshold, it indicates that the linkage coupling relationship between adjacent extraction holes is qualified, the negative pressure disturbance between holes and the gas migration behavior are effectively superimposed, and continuous monitoring is required.

[0032] When the multi-hole linkage coupling coefficient is less than the multi-hole linkage coupling threshold, it indicates that the linkage coupling relationship between adjacent extraction holes is unqualified, and the negative pressure disturbance between holes and the gas migration behavior do not form a synergistic effect. There is a risk of insufficient utilization of multi-hole extraction resources and distortion of effective radius assessment. This triggers a second early warning instruction and generates a second strategy: to perform inter-hole coordination adjustment, adjust the start-stop sequence of adjacent extraction holes by 10% to 30% time misalignment; adjust the extraction negative pressure difference of adjacent extraction holes by 5% to 20% gradient adjustment; and optimize and correct the hole spacing configuration parameters by 10% to 25%. After adjustment, recalculate until the multi-hole linkage coupling coefficient is greater than or equal to the multi-hole linkage coupling threshold, and establish an effective input parameter set, which is then transmitted to the dynamic effective radius assessment module.

[0033] Furthermore, the dynamic effective radius evaluation module includes a sampling response spatial difference feature extraction unit, a third calculation unit, and a third analysis unit;

[0034] The extraction response spatial difference feature extraction unit is used to statistically process the multi-hole linkage coupling coefficient corresponding to the j-th adjacent extraction hole that has a spatial adjacency relationship with the i-th extraction hole, based on the effective input parameter set and using the neighborhood screening and arithmetic mean calculation method. The average value of the multi-hole linkage coupling coefficient of the current extraction hole is obtained by numerical averaging. Based on the original value of the negative pressure at the i-th extraction hole orifice, the original value of the extracted gas flow rate, the original value of the extracted gas concentration, and the extraction response time delay value, the extraction response feature comprehensive analysis method is used to jointly process the negative pressure stability, flow attenuation characteristics, and gas release response characteristics of the i-th extraction hole within a preset time window, quantitatively characterize the degree of extraction response difference in the coal body area corresponding to the current extraction hole, and obtain spatial zoning indicators.

[0035] Furthermore, the third calculation unit is used to calculate and obtain the dynamic effective radius correction coefficient by combining the average value of the multi-hole linkage coupling coefficient and spatial partition index of the i-th extraction hole with the rate of change of gas concentration of the i-th extraction hole over time, after dimensionless processing.

[0036] The third analysis unit is used to obtain a third evaluation result by comparing the dynamic effective radius correction coefficient with the dynamic effective radius correction threshold through a preset dynamic effective radius correction threshold.

[0037] When the dynamic effective radius correction coefficient is less than or equal to the dynamic effective radius correction threshold, it indicates that the current effective radius assessment result of the extraction hole is qualified and should be continuously monitored.

[0038] When the dynamic effective radius correction coefficient exceeds the dynamic effective radius correction threshold, it indicates that the current extraction borehole's effective radius assessment result is unqualified. The effective extraction radius within the coal seam area corresponding to the current extraction borehole does not meet the design requirements, posing a risk of limited effective range or dynamic attenuation. This triggers the third early warning instruction and generates the third strategy: Adjusting the extraction negative pressure in stages, lowering or raising the current extraction borehole's negative pressure setpoint by 5%–15% to improve the local pressure gradient distribution; adjusting the inter-bore collaborative extraction ratio, increasing the collaborative extraction participation ratio of adjacent boreholes associated with the current extraction borehole by 10%–20%; dynamically correcting the extraction sequence, extending or shortening the continuous extraction time by 10%–30% to enhance the continuous gas release capability; after executing the adjustment strategy, re-collecting and updating the dynamic effective radius correction coefficient to form a closed-loop assessment.

[0039] Compared with the prior art, the beneficial effects of the present invention are:

[0040] This invention, by constructing a multi-source data acquisition system encompassing negative pressure at the extraction orifice, gas flow rate, gas concentration, and extraction response time delay, and employing a data processing method that uses unified timestamp alignment and outlier removal, achieves a precise characterization of the physical processes involved in pressure field evolution, gas migration rate, and concentration changes during coal seam gas extraction. Compared to existing methods relying on empirical judgment or single-parameter analysis, this invention establishes a standardized and quantifiable basis for extraction parameters based on the physical coupling relationship between negative pressure, flow rate, and concentration, and the characteristics of gas diffusion dynamics. This significantly improves the objectivity and stability of the effective extraction radius assessment results.

[0041] This invention also introduces a multi-pore linkage coupling analysis mechanism. By comprehensively modeling the negative pressure difference, gas concentration gradient, and spatial distance relationship between adjacent extraction holes, a multi-pore linkage coupling coefficient is established, enabling physical analysis of the superposition effect of gas migration in the coal pore-fracture network. This method breaks through the traditional single-hole perspective evaluation mode, effectively identifying the synergistic or interfering state of negative pressure disturbance between holes and gas diffusion behavior. It avoids the problem of overestimating or underestimating the effective radius due to ignoring the multi-pore coupling effect, thereby improving the resource utilization efficiency of multi-pore extraction and the safety of the overall extraction system.

[0042] This invention further introduces a spatial zoning index based on extraction response characteristics and the average value of the multi-pore linkage coupling coefficient during the dynamic effective radius assessment stage. Combined with the gas concentration change rate, a dynamic effective radius correction coefficient is formed, enabling a comprehensive characterization of the chemical kinetics and physical response characteristics of the gas desorption-diffusion-migration process under heterogeneous coal seam conditions. Through threshold determination and graded adjustment strategy linkage output, the assessment results directly drive the quantitative optimization and adjustment of extraction negative pressure, inter-pore coordination, and extraction timing. This constructs a closed-loop control mechanism of "assessment-early warning-regulation-reassessment," effectively reducing the risk of dynamic decay of the extraction effective radius and improving the long-term stable operation capability of the coal seam gas extraction system. Attached Figure Description

[0043] Figure 1 This is a schematic diagram illustrating the execution of the core logic flow nodes of the overall system of the present invention;

[0044] Figure 2 This is a schematic diagram of the overall system flow and technical route of the present invention. Detailed Implementation

[0045] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0046] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0047] Example 1:

[0048] Please see Figures 1 to 2 The present invention provides a technical solution comprising:

[0049] The data acquisition module is configured to synchronously acquire multiple physical parameters related to the extraction range during the coal seam gas multi-hole extraction process, and obtain raw data of negative pressure at the extraction orifice, raw data of gas flow rate, raw data of gas concentration, extraction response time delay data, and raw coal seam gas pressure data and spatial coordinate information of the extraction orifice.

[0050] The data processing module is configured to perform unified timestamp alignment, outlier identification and removal on the collected data, and establish a standard dataset.

[0051] The extraction impedance assessment module is configured to obtain the average negative pressure value of the extraction orifice and the gas flow rate attenuation rate based on a standard dataset, calculate the extraction impedance coefficient, and compare it with the preset extraction impedance threshold. When the extraction impedance exceeds the threshold, an enhanced adjustment strategy for the single-orifice extraction negative pressure and extraction duration is triggered.

[0052] The multi-hole linkage coupling analysis module is configured to calculate the multi-hole linkage coupling coefficient based on the average extraction negative pressure difference, gas concentration change rate difference, and spatial distance between adjacent extraction holes, and compare it with the preset multi-hole linkage coupling threshold. When the linkage coupling between holes is insufficient, a coordinated adjustment strategy for the start-stop sequence between holes, extraction negative pressure gradient, and hole spacing configuration is triggered, and a set of effective input parameters is generated.

[0053] The dynamic effective radius evaluation module is configured to construct a dynamic effective radius correction coefficient by acquiring the average value of the multi-hole linkage coupling coefficient and the spatial partition index, and compare it with the preset dynamic effective radius correction threshold. When the evaluation result is unqualified, the linkage control strategy for adjusting the extraction negative pressure, adjusting the inter-hole collaborative extraction ratio, and dynamically correcting the extraction timing is triggered. After adjustment, the calculation is recalculated to form a closed-loop evaluation and optimization mechanism.

[0054] Appendix Figure 1 The isometric view on the left illustrates the physical application scenario of this invention: an underground coal seam undergoing multi-hole gas extraction. The coal seam, the multiple extraction boreholes extending into it, and the pipeline system connecting the borehole openings, shown in the figure, collectively constitute the physical basis for the system's data acquisition. The dashed influence area around the boreholes and its overlapping portion visually express the two core physical concepts of "effective radius" and "multi-hole linkage coupling" that this invention focuses on. This scenario corresponds to the operation of the data acquisition module simultaneously acquiring multiple physical parameters such as negative pressure at the extraction borehole openings, gas flow rate, and gas concentration in this environment. (Appendix) Figure 1The technology roadmap on the right illustrates the system's data processing and decision-making flow through four logical block diagrams and their connections. "Multi-source data acquisition and processing" represents the system's input and preprocessing stages, corresponding to the data acquisition module acquiring raw data and the data processing module performing timestamp alignment and outlier removal to establish a standard dataset. "Impedance and coupling coefficient evaluation" represents the system's core analysis and calculation stage, corresponding to the extraction impedance evaluation module calculating the extraction impedance coefficient and the multi-pore linkage coupling analysis module calculating the multi-pore linkage coupling coefficient. "Effective radius dynamic evaluation" demonstrates the system's comprehensive evaluation stage, corresponding to the dynamic effective radius evaluation module. This module constructs a dynamic effective radius correction coefficient and compares it with a preset threshold to determine the effectiveness of the current extraction radius. "Closed-loop control and optimization" clarifies the system's final output and decision-making closed-loop mechanism. When the results of "impedance and coupling coefficient evaluation" or "effective radius dynamic evaluation" are abnormal, the system will trigger corresponding collaborative adjustment strategies or linkage control strategies. After adjustment, the system process returns to the evaluation stage, forming a closed-loop optimization of "evaluation-control-re-evaluation", thereby achieving dynamic correction of the effective sampling radius.

[0055] In this embodiment, a hierarchical evaluation and closed-loop control mechanism for coal seam gas multi-hole drainage is constructed by modularly integrating data acquisition, data processing, drainage impedance assessment, multi-hole linkage coupling analysis, and dynamic effective radius assessment. This mechanism, based on unified time-series processing and physical correlation analysis of multi-source physical parameters, identifies key issues such as insufficient single-hole drainage, inter-hole linkage failure, and dynamic decay of the effective drainage radius. It then triggers targeted negative pressure, time-series, and coordinated drainage adjustment strategies, allowing the effective drainage radius assessment results to directly participate in drainage parameter optimization decisions. This avoids the disconnect between assessment results and on-site control in traditional methods, significantly improving the accuracy of coal seam gas drainage range assessment, the executability of control strategies, and the overall safety and stability of the drainage system.

[0056] Example 2

[0057] Please see Figures 1 to 2 In the explanation of Embodiment 1, the data acquisition module specifically includes a negative pressure extraction flow acquisition unit, a gas concentration response time acquisition unit, and a coal seam original state spatial information acquisition unit.

[0058] The negative pressure extraction flow acquisition unit is used to monitor the changes in extraction intensity of each extraction hole in real time under the multi-hole extraction condition of coal seam gas; by installing negative pressure sensors at the orifice of each extraction hole, the original value of the negative pressure at the orifice is acquired in real time and recorded as follows. By installing gas flow meters on the extraction pipelines of each extraction hole, the raw value of the extracted gas flow rate is collected in real time and recorded as follows: ;

[0059] The gas concentration response time acquisition unit is used to monitor the gas release response characteristics in real time during coal seam gas extraction; by installing a gas concentration sensor at the outlet of the extraction hole or the end of the extraction pipeline, the raw value of the extracted gas concentration is acquired in real time and recorded as follows. The extraction response time delay value is obtained by synchronously recording the time of change in negative pressure at the extraction orifice and the time of significant changes in gas concentration or extraction flow rate, and is denoted as . ;

[0060] The original state spatial information acquisition unit of the coal seam is used to monitor the basic occurrence conditions of the coal seam in the extraction area in real time; by conducting gas pressure tests at the borehole test location or historical exploration point location, or by calling historical geological measurement data, the original gas pressure of the coal seam is obtained and recorded as P0; the spatial coordinate information of the extraction hole is obtained by measuring the location of each extraction hole through the downhole measurement system and recorded as (x, y, z).

[0061] In this embodiment, by coordinating the negative pressure extraction flow rate acquisition unit, the gas concentration response time acquisition unit, and the coal seam original state spatial information acquisition unit, the synchronous perception and unified representation of the physical behavior of the entire process of "extraction drive - gas release - coal seam occurrence conditions" during coal seam gas multi-hole extraction are realized. This enables joint physical analysis of the negative pressure at the extraction orifice, gas flow rate, and gas concentration response time under the same spatial coordinate system and time reference. This avoids the errors caused by relying solely on empirical judgments based on a single negative pressure or flow rate parameter, and improves the ability to identify the gas release response lag, the effectiveness of extraction, and the impact of coal seam heterogeneity. It provides a physically consistent and highly reliable basic data support for subsequent extraction impedance analysis and effective radius dynamic evaluation.

[0062] Example 3

[0063] Please see Figures 1 to 2 In this embodiment, as explained in Embodiment 1, the data processing module is used to perform time synchronization processing on the time series data of the original values ​​of the negative pressure at the extraction orifice, the original values ​​of the extracted gas flow rate, and the original values ​​of the extracted gas concentration using a unified timestamp alignment method; then, it uses an outlier identification and removal method to filter out abrupt changes in data caused by instantaneous sensor interference and communication anomalies; and finally, it establishes a standard dataset.

[0064] In this embodiment, by introducing a unified timestamp alignment and outlier identification and removal mechanism in the data processing module, the temporal consistency correction and physical rationality screening of multi-source time series data such as extraction orifice negative pressure, gas flow rate, and gas concentration are realized. This effectively eliminates the impact of differences in sampling frequencies of different sensors, instantaneous interference, and communication jitter on the analysis results, enabling the data used in subsequent calculations to truly reflect the continuous physical process of coal seam gas migration and extraction response. This improves the stability, reliability, and repeatability of the extraction action impedance, multi-orifice linkage coupling, and effective radius evaluation results.

[0065] Example 4

[0066] Please see Figures 1 to 2 In the explanation of Embodiment 1, the extraction impedance assessment module specifically includes a single-hole extraction intensity parameter extraction unit, a first calculation unit, and a first analysis unit.

[0067] The single-hole extraction intensity parameter extraction unit is used to extract the original negative pressure value of the i-th extraction hole in the standard dataset, denoted as... The arithmetic mean algorithm was used to obtain the average negative pressure value at the orifice during the stable extraction phase, denoted as . Extract the raw value of the gas flow rate from the i-th extraction hole, denoted as . The method of calculating the rate of change per unit time is used to process the variation of extracted gas flow over time. By calculating the difference in flow rate between adjacent time points and the corresponding time interval, the gas flow rate attenuation rate per unit time is obtained, denoted as . ;

[0068] The first calculation unit is used to obtain the average negative pressure value at the orifice during the stable extraction phase. and the gas flow rate attenuation rate at the i-th extraction orifice Combining the original coal seam gas pressure P0 and the extraction response time delay value of the i-th extraction orifice, it is denoted as... After dimensionless processing, a weighted linear synthesis algorithm is used to calculate the sampling impedance coefficient, denoted as ZKX, as shown in the following formula:

[0069]

[0070] In the formula, w1, w2 and w3 represent weighting coefficients.

[0071] This index is used to characterize the influence of the original gas pressure difference in the coal seam on the resistance coefficient of the extraction action, and it accounts for the main weight. This index reflects the magnitude of the driving force for the release of coal seam gas pressure after the extraction hole establishes negative pressure. It directly reflects the basic ability of the extraction system to overcome the seepage resistance of the coal body and is the core factor affecting the extraction efficiency and stability.

[0072] : Used to characterize the effect of gas flow decay rate on the extraction resistance coefficient, with medium weight; This index reflects the rate at which gas production capacity decreases over time during continuous extraction, and is used to characterize the degree to which the coal body permeability structure and pore connectivity state restrict the continuity of extraction.

[0073] 5: Used to characterize the effect of extraction response time delay on the extraction impedance coefficient, accounting for a minor weight; this index reflects the time characteristics required for the extraction negative pressure to be transmitted to the coal seam and trigger the gas response, and is used to describe the influence of the complexity of the coal medium structure and the local hysteresis effect on the extraction impedance.

[0074] By constructing a sampling impedance coefficient ZKX, which is a weighted fusion of pressure difference, flow rate attenuation, and response delay terms, the comprehensive resistance level faced by a single well during the stable sampling phase can be comprehensively quantified, providing a basic quantitative basis for subsequent sampling status judgment and control strategies.

[0075] In this embodiment, by constructing a drainage action impedance assessment module, multi-dimensional physical parameters such as orifice negative pressure, gas flow attenuation characteristics, and drainage response time delay are uniformly dimensionless. A weighted linear synthesis algorithm is then used to form the drainage action impedance coefficient. This enables a quantitative characterization of the coupling relationship between "negative pressure intensity - gas release dynamics - coal seam occurrence state" during single-hole drainage. It can accurately identify the mismatch between drainage negative pressure and coal gas desorption and seepage response from the physical mechanism level, thereby avoiding misjudgments caused by relying solely on a single negative pressure or flow rate index. This improves the scientificity and pertinence of single-hole drainage effect assessment and enhanced adjustment decisions.

[0076] Example 5

[0077] Please see Figures 1 to 2 In the explanation of Embodiment 4, specifically, the first analysis unit is used to compare and analyze the sampling impedance coefficient ZKX with the sampling impedance threshold Zth by setting a preset sampling impedance threshold, denoted as Zth, to obtain the first evaluation result, including:

[0078] When the extraction impedance coefficient ZKX ≤ extraction impedance threshold Zth, it indicates that the current extraction impedance of the extraction hole is within a controllable range and should be continuously monitored.

[0079] When the extraction impedance coefficient ZKX > the extraction impedance threshold Zth, it indicates that the extraction impedance of the current extraction hole exceeds the controllable range, and there is a risk that the extraction negative pressure is insufficient to effectively affect the coal body, the gas release rate is mismatched with the extraction intensity, or the extraction influence range is limited. This triggers the first warning command and generates the first strategy: implement a single-hole enhanced extraction strategy for the current extraction hole, increase the extraction negative pressure parameter of the corresponding extraction hole by 5% to 15% incrementally, and extend the extraction duration by 10% to 20%. After adjustment, recalculate until the extraction impedance coefficient ZKX ≤ the extraction impedance threshold Zth.

[0080] The method for obtaining the extraction impedance threshold Zth is as follows: Through statistical analysis of a large amount of field operation data of coal seam gas extraction, the distribution range of extraction impedance coefficients corresponding to key physical parameters such as orifice negative pressure, gas flow attenuation rate, and extraction response time delay are extracted under smooth and obstructed extraction conditions. Combined with the physical analysis results of the coal seam gas migration mechanism and the experience judgment of mine gas extraction engineers, a critical judgment value is determined that can distinguish between a controllable extraction state and a significantly restricted extraction state. Referring to current coal mine gas extraction technical specifications, safety regulations, and engineering design parameters, this threshold is used to identify the risk state of insufficient negative pressure or obstructed gas release during single-orifice extraction.

[0081] In this embodiment, by introducing a threshold value for the extraction action impedance in the first analysis unit and performing threshold discrimination on the extraction action impedance coefficient, a graded assessment and automatic early warning of the single-hole extraction status is realized. When abnormal working conditions such as insufficient extraction negative pressure or lag in gas release dynamic response are identified, a quantitative strengthening adjustment strategy for the extraction negative pressure amplitude and extraction duration can be triggered in a timely manner based on the physical action mechanism. Through the closed-loop control method of "assessment-adjustment-recalculation", the extraction action status is gradually returned to the controllable range, thereby effectively avoiding the problem of long-term low extraction efficiency or limited action range, and improving the stability and safety of the coal seam gas extraction process.

[0082] Example 6

[0083] Please see Figures 1 to 2 In the explanation of Embodiment 1, the multi-pore linkage coupling analysis module specifically includes a pore coupling feature parameter extraction unit, a second calculation unit, and a second analysis unit.

[0084] The inter-hole coupling feature parameter extraction unit is used to extract the original value of the negative pressure at the i-th extraction orifice in the standard dataset. The original negative pressure value of the j-th adjacent extraction orifice is denoted as... The arithmetic average algorithm is used to obtain the average negative pressure value of the i-th adjacent extraction well within a preset time window. The average negative pressure value of the j-th extraction well within the preset time window is denoted as . Extract the raw value of the gas concentration from the i-th extraction well in the standard dataset. The original value of the gas concentration extracted from the j-th extraction well is denoted as... The time gradient calculation method is used to process the trend of gas concentration change over time. By calculating the ratio of the change in gas concentration at adjacent sampling times to the time interval, the rate of change of gas concentration over time at the i-th sampling well is obtained, denoted as . The rate of change of gas concentration over time at the j-th extraction well is denoted as . Based on the spatial coordinate information (x, y, z) of the extraction holes, the spatial distance between the i-th and j-th extraction holes is obtained using an inverse spatial distance calculation method, denoted as . .

[0085] In this embodiment, the negative pressure intensity, gas concentration evolution characteristics, and spatial distance relationship between adjacent extraction holes are simultaneously quantified and extracted through the inter-hole coupling feature parameter extraction unit. A physical characterization method of time gradient and spatial inverse ratio analysis is introduced to enable the coupling relationship between inter-hole negative pressure disturbance and gas migration behavior to be finely characterized. This effectively avoids misjudgment of linkage relationship caused by relying on a single extraction parameter, improves the accuracy and reliability of inter-hole mutual influence identification during multi-hole extraction, and provides a stable and interpretable physical analysis basis for subsequent multi-hole linkage coupling analysis and coordinated control.

[0086] Example 7

[0087] Please see Figures 1 to 2 In the explanation of Embodiment Six, specifically, the second calculation unit is used to obtain the average extraction negative pressure value of the adjacent i-th extraction hole within a preset time window. and the average negative pressure value of the j-th extraction hole within the preset time window The rate of change of gas concentration in the i-th extraction well over time The rate of change of gas concentration over time at the j-th extraction well. Combining the spatial distance between the i-th and j-th extraction holes After dimensionless processing of the original gas pressure P0 in the coal seam, the multi-pore linkage coupling coefficient, denoted as LDOX, is calculated and obtained, as shown in the following formula:

[0088]

[0089] In the formula, a1, a2 and a3 represent weighting coefficients.

[0090] This indicator is used to characterize the influence of the average negative pressure difference between adjacent extraction holes on the multi-hole linkage coupling coefficient, and has a high weight. This indicator directly reflects the interaction strength of the negative pressure fields of different extraction holes and is an important physical quantity for measuring the extraction interference and synergistic effect between holes.

[0091] This index is used to characterize the impact of differences in gas concentration changes between adjacent extraction holes on the multi-hole linkage coupling coefficient, and has a medium weight. This index reflects the consistency of different extraction holes' responses to coal seam gas release, and is used to describe the synchronicity and coupling degree of extraction behavior between holes.

[0092] 5: Used to characterize the influence of the spatial distance of extraction holes on the multi-hole linkage coupling coefficient, accounting for a minor weight; this index is used to describe the spatial attenuation characteristics of the coupling effect of the geometric distribution between holes on negative pressure transmission and gas migration.

[0093] By constructing a multi-hole linkage coupling coefficient LDOX, which is a weighted fusion of negative pressure difference, gas concentration variation difference and hole distance, the collaborative extraction capacity and mutual influence of multiple extraction holes in the same coal seam area can be quantitatively evaluated, providing a basis for hole group collaborative control.

[0094] In this embodiment, the second calculation unit integrates multiple physical quantities such as the average negative pressure difference between wells, the difference in gas concentration change rate, and the spatial distance between wells in a dimensionless manner to construct the multi-well linkage coupling coefficient LDOX, thereby realizing a quantitative characterization of the coupling degree between the negative pressure transmission effect between wells and the gas migration response. This calculation method can effectively reduce the interference of different dimensional parameters on the evaluation results, enhance the stability and comparability of the determination of the synergistic effect between wells, and thus improve the objectivity and engineering applicability of the multi-well extraction linkage effect evaluation.

[0095] Example 8

[0096] Please see Figures 1 to 2 In the explanation of Embodiment Six, specifically, the second analysis unit is used to compare and analyze the multi-hole linkage coupling coefficient LDOX with the multi-hole linkage coupling threshold Lth to obtain the second evaluation result, including:

[0097] When the multi-hole linkage coupling coefficient LDOX ≥ the multi-hole linkage coupling threshold Lth, it indicates that the linkage coupling relationship between adjacent extraction holes is qualified, the negative pressure disturbance between holes and the gas migration behavior form an effective superposition, and continuous monitoring is required.

[0098] When the multi-hole linkage coupling coefficient LDOX < the multi-hole linkage coupling threshold Lth, it indicates that the linkage coupling relationship between adjacent extraction holes is unqualified, and the negative pressure disturbance between holes and the gas migration behavior do not form a synergistic effect. There is a risk of insufficient utilization of multi-hole extraction resources and distortion of effective radius assessment. This triggers a second early warning instruction and generates a second strategy: to perform inter-hole coordination adjustment, adjust the start and stop sequence of adjacent extraction holes by 10% to 30% time misalignment; adjust the extraction negative pressure difference of adjacent extraction holes by 5% to 20% gradient adjustment; and optimize and correct the hole spacing configuration parameters by 10% to 25%. After adjustment, recalculate until the multi-hole linkage coupling coefficient LDOX ≥ the multi-hole linkage coupling threshold Lth, and establish an effective input parameter set, which is then passed to the dynamic effective radius assessment module.

[0099] The multi-hole linkage coupling threshold Lth is obtained by statistically analyzing a large amount of operational data from adjacent drainage holes under multi-hole joint drainage conditions. This analysis extracts the distribution range of multi-hole linkage coupling coefficients for coupling characteristic parameters such as inter-hole negative pressure difference, gas concentration change rate difference, and hole spacing under effective and weak linkage states. Combined with the analysis of the physical coupling mechanism between coal seam porous seepage and gas migration, and practical experience in field control, the critical judgment value for effective synergy between adjacent drainage holes is determined. Referring to coal mine gas drainage hole layout design specifications and drainage system operation experience, this threshold is used to distinguish between effective and insufficient linkage in inter-hole collaborative drainage operation.

[0100] In this embodiment, the second analysis unit compares the multi-hole linkage coupling coefficient LDOX with the preset multi-hole linkage coupling threshold Lth to clearly distinguish the qualified and unqualified states of the linkage coupling relationship between adjacent extraction holes. When the linkage coupling is insufficient, physical control strategies such as start-stop timing misalignment, extraction negative pressure gradient adjustment, and hole spacing configuration optimization are introduced to achieve coordinated reconstruction of the negative pressure field and gas migration field between holes. This effectively avoids the problems of insufficient utilization of multi-hole extraction resources and distortion of effective radius assessment. Furthermore, by repeatedly recalculating, a stable and reliable set of effective input parameters is established, providing a highly reliable data foundation for subsequent dynamic effective radius assessment.

[0101] Example 9

[0102] Please see Figures 1 to 2 In the explanation of Embodiment 1, the dynamic effective radius evaluation module specifically includes a sampling response spatial difference feature extraction unit, a third calculation unit, and a third analysis unit.

[0103] The extraction response spatial difference feature extraction unit is used to statistically process the multi-hole linkage coupling coefficient LDOX corresponding to the j-th adjacent extraction hole that has a spatial adjacency relationship with the i-th extraction hole, based on the effective input parameter set and using a neighborhood screening and arithmetic mean calculation method. The average value of the multi-hole linkage coupling coefficient is obtained by numerically averaging to obtain the mean value of the multi-hole linkage coupling coefficient of the current overall multi-hole linkage coupling level, denoted as . Based on the original negative pressure value of the i-th extraction orifice. Raw values ​​of gas extraction flow Raw values ​​of extracted gas concentration and the sampling response time delay value A comprehensive analysis method for extraction response characteristics is adopted to jointly process the negative pressure stability, flow rate attenuation characteristics, and gas release response characteristics of the i-th extraction hole within a preset time window. This quantitatively characterizes the degree of difference in extraction response in the coal seam region corresponding to the current extraction hole, and obtains spatial zoning indicators, denoted as . .

[0104] In this embodiment, the spatial difference feature extraction unit of the extraction response is used to perform neighborhood screening and arithmetic averaging on the multi-hole linkage coupling coefficient of adjacent extraction holes. Combined with the comprehensive analysis of multi-source physical parameters such as hole negative pressure, gas flow rate, gas concentration and extraction response time delay, the degree of extraction response difference in the coal body region is quantitatively characterized from the two levels of physical response and mass transfer behavior. This can effectively reflect the impact of local heterogeneous conditions of the coal seam on gas migration and extraction efficiency, thereby providing a stable and interpretable spatial zoning index basis for dynamic effective radius correction, and significantly improving the accuracy and regional adaptability of effective radius assessment.

[0105] Example 10

[0106] Please see Figures 1 to 2 In the explanation of Embodiment Nine, specifically, the third calculation unit is used to obtain the average value of the multi-hole linkage coupling coefficient of the i-th extraction hole. Spatial zoning indicators Combined with the rate of change of gas concentration over time at the i-th extraction well After dimensionless processing, the dynamic effective radius correction coefficient, denoted as Rd, is calculated and obtained, as shown in the following formula:

[0107]

[0108] In the formula, s1, s2 and s3 represent weighting coefficients;

[0109] This index is used to characterize the impact of spatial zoning indicators on the dynamic effective radius correction coefficient and accounts for the main weight. This index reflects the basic constraints of different geological zones, structural conditions and coal occurrence characteristics on the effective range of extraction.

[0110] This index is used to characterize the influence of the multi-hole linkage coupling effect on the dynamic effective radius correction coefficient, and has a medium weight; this index is used to describe the degree of influence of the coordinated extraction state of the hole group on the expansion or contraction of the effective radius of a single hole.

[0111] This indicator is used to characterize the effect of the rate of change of gas concentration on the dynamic effective radius correction coefficient, and has a minor weight; it reflects the degree of activity of coal seam gas release and the dynamic change characteristics of the extraction response.

[0112] By constructing a dynamic effective radius correction coefficient Rd that is a weighted fusion of spatial partitioning factors, multi-hole linkage coupling effect and gas dynamic response characteristics, the actual effective range of the extraction hole can be dynamically corrected, and a quantitative assessment of the attenuation or expansion trend of the extraction effective radius can be achieved, providing a physical basis for the adaptive adjustment of the extraction strategy.

[0113] The third analysis unit is used to compare and analyze the dynamic effective radius correction coefficient Rd with the dynamic effective radius correction threshold Rth using a preset dynamic effective radius correction threshold to obtain the third evaluation result, including:

[0114] When the dynamic effective radius correction coefficient Rd ≤ the dynamic effective radius correction threshold Rth, it indicates that the current effective radius assessment result of the extraction hole is qualified and should be continuously monitored.

[0115] When the dynamic effective radius correction coefficient Rd > the dynamic effective radius correction threshold Rth, it indicates that the current extraction hole's effective radius assessment result is unqualified, and the extraction effective radius within the coal seam area corresponding to the current extraction hole does not meet the design requirements, posing a risk of limited effective range or dynamic attenuation. This triggers the third early warning instruction and generates the third strategy: Adjusting the extraction negative pressure in stages, lowering or raising the current extraction hole's negative pressure setting value by 5%–15% to improve the local pressure gradient distribution; adjusting the inter-hole collaborative extraction ratio, increasing the collaborative extraction participation ratio of adjacent holes associated with the current extraction hole by 10%–20%; dynamically correcting the extraction sequence, extending or shortening the continuous extraction time by 10%–30% to enhance the continuous gas release capability; after executing the adjustment strategy, re-collecting and updating the dynamic effective radius correction coefficient Rd to form a closed-loop assessment.

[0116] The dynamic effective radius correction threshold Rth is obtained by conducting long-term statistical analysis of gas drainage effect data under different coal seam conditions and different drainage stages. The distribution range of the dynamic effective radius correction coefficient is extracted for the stable expansion state and the decay or limitation state of the effective radius. Combined with the physical analysis results of the influence of coal seam heterogeneity on the drainage range and mine gas control engineering experience, a critical correction threshold is determined to judge whether the effective drainage radius meets the design requirements. Referring to mine gas control design specifications and drainage effect evaluation standards, this threshold is used to distinguish between a stable and maintainable effective drainage radius and a state with dynamic decay risk.

[0117] In this embodiment, the spatial zoning index, the average value of the multi-hole linkage coupling coefficient, and the rate of change of gas concentration over time are dimensionlessly fused by the third calculation unit to construct a dynamic effective radius correction coefficient. Combined with threshold discrimination and graded control strategies, continuous physical analysis and dynamic correction of the effective radius state of coal seam gas extraction are achieved. When the evaluation result is unqualified, multi-dimensional linkage control methods such as pressure gradient adjustment, optimization of inter-hole collaborative extraction ratio, and time sequence correction can be used to specifically improve the gas migration and release conditions, avoid effective radius decay or evaluation distortion, thereby improving the stability and safety of the extraction system operation and the engineering reliability of the effective radius evaluation results.

[0118] It should be noted that all calculation formulas in this application employ regression analysis, including but not limited to machine learning algorithms, to deeply analyze the collected parameters and identify their natural trends and interrelationships. Specialized software, such as Python's Sckt-learn library or the R language, is used to automatically generate mathematical models that match the data. Then, cross-validation and other methods are used to objectively evaluate the model performance, and continuous feedback and optimization are combined to ensure that the created formulas truly reflect the inherent laws of the data, thereby guaranteeing their effectiveness and accuracy. In all calculation formulas in this application, the parameters in each formula undergo dimensionless processing within a consistent range to ensure that different physical quantities are compared on the same scale; dimensionless processing techniques include, but are not limited to, Mn-Max-Normalzaton and Z-Score standardization.

[0119] The algorithm of this invention is implemented as a Python script. Before executing the core logic, the program first executes a data loading module (e.g., using the widely used pandas library in Python) configured to read the aforementioned spreadsheet file and load its contents into the program's working memory (e.g., a DataFrame data structure). Subsequent algorithm steps will directly query and retrieve the required configuration parameters from this in-memory data structure.

[0120] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A dynamic evaluation system for the effective radius of coal seam gas extraction based on multi-pore linkage coupling, characterized in that, include: The data acquisition module is configured to synchronously acquire multiple physical parameters related to the extraction range during the coal seam gas multi-hole extraction process, and obtain raw data of negative pressure at the extraction orifice, raw data of gas flow rate, raw data of gas concentration, extraction response time delay data, and raw coal seam gas pressure data and spatial coordinate information of the extraction orifice. The data processing module is configured to perform unified timestamp alignment, outlier identification and removal on the collected data, and establish a standard dataset. The extraction impedance assessment module is configured to obtain the average negative pressure value of the extraction orifice and the gas flow rate attenuation rate based on a standard dataset, calculate the extraction impedance coefficient, and compare it with the preset extraction impedance threshold. When the extraction impedance exceeds the threshold, an enhanced adjustment strategy for the single-orifice extraction negative pressure and extraction duration is triggered. The multi-hole linkage coupling analysis module is configured to calculate the multi-hole linkage coupling coefficient based on the average extraction negative pressure difference, gas concentration change rate difference, and spatial distance between adjacent extraction holes, and compare it with the preset multi-hole linkage coupling threshold. When the linkage coupling between holes is insufficient, a coordinated adjustment strategy for the start-stop sequence between holes, extraction negative pressure gradient, and hole spacing configuration is triggered, and a set of effective input parameters is generated. The multi-hole linkage coupling coefficient is obtained by acquiring the average extraction negative pressure value of the i-th adjacent extraction hole within a preset time window. and the average negative pressure value of the j-th extraction hole within the preset time window The rate of change of gas concentration in the i-th extraction well over time The rate of change of gas concentration over time at the j-th extraction well. Combining the spatial distance between the i-th and j-th extraction holes After dimensionless processing of the original gas pressure P0 in the coal seam, the multi-pore linkage coupling coefficient, denoted as LDOX, is calculated and obtained, as shown in the following formula: In the formula, a1, a2, and a3 represent weighting coefficients; The dynamic effective radius evaluation module is configured to construct a dynamic effective radius correction coefficient by acquiring the average value of the multi-hole linkage coupling coefficient and the spatial partition index, and compare it with the preset dynamic effective radius correction threshold. When the evaluation result is unqualified, the linkage control strategy for adjusting the extraction negative pressure, adjusting the inter-hole collaborative extraction ratio, and dynamically correcting the extraction timing is triggered. After adjustment, the calculation is recalculated to form a closed-loop evaluation and optimization mechanism. The dynamic effective radius correction coefficient is obtained by using the average value of the multi-hole linkage coupling coefficient of the i-th extraction hole. Spatial zoning indicators Combined with the rate of change of gas concentration over time at the i-th extraction well After dimensionless processing, the dynamic effective radius correction coefficient, denoted as Rd, is calculated and obtained, as shown in the following formula: In the formula, s1, s2 and s3 represent weighting coefficients.

2. The dynamic evaluation system for the effective radius of coal seam gas extraction based on multi-pore linkage coupling according to claim 1, characterized in that: The data acquisition module includes a negative pressure extraction flow acquisition unit, a gas concentration response time acquisition unit, and a coal seam original state spatial information acquisition unit. The negative pressure extraction flow acquisition unit is used to monitor the changes in extraction intensity of each extraction hole in real time under the multi-hole extraction condition of coal seam gas; by installing negative pressure sensors at the opening of each extraction hole, the original value of negative pressure at the extraction hole opening is acquired in real time. By installing gas flow meters on the extraction pipelines of each extraction hole, the raw value of the extracted gas flow rate is collected in real time. The gas concentration response time acquisition unit is used to monitor the gas release response characteristics in real time during coal seam gas extraction. By installing a gas concentration sensor at the outlet of the extraction hole or the end of the extraction pipeline, the raw value of the extracted gas concentration is acquired in real time. The extraction response time delay value is obtained by synchronously recording the time of negative pressure change at the extraction hole and the time when the gas concentration or extraction flow rate changes significantly. The original state spatial information acquisition unit of the coal seam is used to monitor the basic occurrence conditions of the coal seam in the extraction area in real time; the original gas pressure of the coal seam is obtained by conducting gas pressure tests at borehole test locations or historical exploration points, or by calling historical geological measurement data; and the spatial coordinate information of the extraction holes is obtained by measuring the location of each extraction hole through the downhole measurement system.

3. The dynamic evaluation system for the effective radius of coal seam gas extraction based on multi-pore linkage coupling according to claim 1, characterized in that: The data processing module is used to perform time synchronization processing on the time series data of the original values ​​of negative pressure at the extraction orifice, the original values ​​of gas flow rate, and the original values ​​of gas concentration using a unified timestamp alignment method; then, it uses outlier identification and removal methods to filter out abrupt changes in data caused by instantaneous sensor interference and communication anomalies; and finally, it establishes a standard dataset.

4. The dynamic evaluation system for the effective radius of coal seam gas extraction based on multi-pore linkage coupling according to claim 1, characterized in that: The extraction impedance assessment module includes a single-hole extraction intensity parameter extraction unit, a first calculation unit, and a first analysis unit. The single-hole extraction intensity parameter extraction unit is used to extract the original negative pressure value of the i-th extraction hole in the standard dataset, and obtain the average negative pressure value of the hole during the stable extraction stage by using an arithmetic average algorithm; it also extracts the original value of the gas flow rate of the i-th extraction hole, and processes the change of the gas flow rate over time by using a unit time change rate calculation method; and obtains the gas flow rate decay rate per unit time by calculating the flow rate difference between adjacent time points and the corresponding time interval. The first calculation unit is used to calculate the extraction resistance coefficient by combining the average negative pressure value of the orifice during the stable extraction stage and the gas flow attenuation rate of the i-th extraction orifice, along with the original gas pressure of the coal seam and the extraction response time delay value of the i-th extraction orifice, after dimensionless processing, using a weighted linear synthesis algorithm.

5. The dynamic evaluation system for the effective radius of coal seam gas extraction based on multi-pore linkage coupling according to claim 4, characterized in that: The first analysis unit is used to obtain a first evaluation result by comparing the sampling impedance coefficient with the sampling impedance threshold through a preset sampling impedance threshold. When the extraction impedance coefficient is less than or equal to the extraction impedance threshold, it indicates that the current extraction impedance of the extraction hole is within a controllable range and should be continuously monitored. When the extraction impedance coefficient exceeds the extraction impedance threshold, it indicates that the extraction impedance of the current extraction hole exceeds the controllable range. This poses a risk of insufficient effective action of the extraction negative pressure on the coal body, mismatch between the gas release rate and extraction intensity, or limited extraction influence range. This triggers the first warning instruction and generates the first strategy: implement a single-hole enhanced extraction strategy for the current extraction hole, increase the extraction negative pressure parameter of the corresponding extraction hole by 5% to 15% incrementally, and extend the extraction duration by 10% to 20%. After adjustment, recalculate until the extraction impedance coefficient is less than or equal to the extraction impedance threshold.

6. The dynamic evaluation system for the effective radius of coal seam gas extraction based on multi-pore linkage coupling according to claim 1, characterized in that: The multi-pore linkage coupling analysis module includes a pore coupling feature parameter extraction unit, a second calculation unit, and a second analysis unit. The inter-hole coupling feature parameter extraction unit is used to extract the original negative pressure value of the i-th extraction orifice and the original negative pressure value of the adjacent j-th extraction orifice in the standard dataset. The arithmetic mean algorithm is used to obtain the average negative pressure value of the i-th and j-th adjacent extraction holes within a preset time window. The original values ​​of the gas concentration of the i-th and j-th extraction holes are extracted from the standard dataset. The time gradient calculation method is used to process the trend of gas concentration change over time. By calculating the ratio of the change in gas concentration at adjacent sampling times to the time interval, the rate of change of gas concentration of the i-th and j-th extraction holes over time is obtained. Based on the spatial coordinate information of the extraction holes, the spatial distance between the i-th extraction hole and the j-th extraction hole is obtained by using the inverse spatial distance calculation method.

7. The dynamic evaluation system for the effective radius of coal seam gas extraction based on multi-pore linkage coupling according to claim 6, characterized in that: The second calculation unit is used to calculate the multi-hole linkage coupling coefficient by acquiring the average negative pressure value of the adjacent i-th extraction hole and the average negative pressure value of the j-th extraction hole within a preset time window, the rate of change of gas concentration of the i-th extraction hole with time and the rate of change of gas concentration of the j-th extraction hole with time, and combining the spatial distance between the i-th and j-th extraction holes and the original gas pressure of the coal seam, after dimensionless processing.

8. The dynamic evaluation system for the effective radius of coal seam gas extraction based on multi-pore linkage coupling according to claim 6, characterized in that: The second analysis unit is used to obtain a second evaluation result by comparing the multi-pore linkage coupling coefficient with a preset multi-pore linkage coupling threshold and performing comparative analysis. When the multi-hole linkage coupling coefficient is greater than or equal to the multi-hole linkage coupling threshold, it indicates that the linkage coupling relationship between adjacent extraction holes is qualified, the negative pressure disturbance between holes and the gas migration behavior are effectively superimposed, and continuous monitoring is required. When the multi-hole linkage coupling coefficient is less than the multi-hole linkage coupling threshold, it indicates that the linkage coupling relationship between adjacent extraction holes is unqualified, and the negative pressure disturbance between holes and the gas migration behavior do not form a synergistic effect. There is a risk of insufficient utilization of multi-hole extraction resources and distortion of effective radius assessment. This triggers a second early warning instruction and generates a second strategy: to perform inter-hole coordination adjustment, adjust the start-stop sequence of adjacent extraction holes by 10% to 30% time misalignment; adjust the extraction negative pressure difference of adjacent extraction holes by 5% to 20% gradient adjustment; and optimize and correct the hole spacing configuration parameters by 10% to 25%. After adjustment, recalculate until the multi-hole linkage coupling coefficient is greater than or equal to the multi-hole linkage coupling threshold, and establish an effective input parameter set, which is then transmitted to the dynamic effective radius assessment module.

9. The dynamic evaluation system for the effective radius of coal seam gas extraction based on multi-pore linkage coupling according to claim 1, characterized in that: The dynamic effective radius evaluation module includes a sampling response spatial difference feature extraction unit, a third calculation unit, and a third analysis unit; The extraction response spatial difference feature extraction unit is used to statistically process the multi-hole linkage coupling coefficient corresponding to the j-th adjacent extraction hole that has a spatial adjacency relationship with the i-th extraction hole, based on the effective input parameter set and using the neighborhood screening and arithmetic mean calculation method. The average value of the multi-hole linkage coupling coefficient of the current extraction hole is obtained by numerical averaging. Based on the original value of the negative pressure at the i-th extraction hole orifice, the original value of the extracted gas flow rate, the original value of the extracted gas concentration, and the extraction response time delay value, the extraction response feature comprehensive analysis method is used to jointly process the negative pressure stability, flow attenuation characteristics, and gas release response characteristics of the i-th extraction hole within a preset time window, quantitatively characterize the degree of extraction response difference in the coal body area corresponding to the current extraction hole, and obtain spatial zoning indicators.

10. The dynamic evaluation system for the effective radius of coal seam gas extraction based on multi-pore linkage coupling according to claim 9, characterized in that: The third calculation unit is used to calculate the dynamic effective radius correction coefficient by combining the average value of the multi-hole linkage coupling coefficient and spatial partition index of the i-th extraction hole with the rate of change of gas concentration of the i-th extraction hole over time and after dimensionless processing. The third analysis unit is used to obtain a third evaluation result by comparing the dynamic effective radius correction coefficient with the dynamic effective radius correction threshold through a preset dynamic effective radius correction threshold. When the dynamic effective radius correction coefficient is less than or equal to the dynamic effective radius correction threshold, it indicates that the current effective radius assessment result of the extraction hole is qualified and should be continuously monitored. When the dynamic effective radius correction coefficient exceeds the dynamic effective radius correction threshold, it indicates that the current extraction borehole's effective radius assessment result is unqualified. The effective extraction radius within the coal seam area corresponding to the current extraction borehole does not meet the design requirements, posing a risk of limited effective range or dynamic attenuation. This triggers the third early warning instruction and generates the third strategy: Adjusting the extraction negative pressure in stages, lowering or raising the current extraction borehole's negative pressure setpoint by 5%–15% to improve the local pressure gradient distribution; adjusting the inter-bore collaborative extraction ratio, increasing the collaborative extraction participation ratio of adjacent boreholes associated with the current extraction borehole by 10%–20%; dynamically correcting the extraction sequence, extending or shortening the continuous extraction time by 10%–30% to enhance the continuous gas release capability; after executing the adjustment strategy, re-collecting and updating the dynamic effective radius correction coefficient to form a closed-loop assessment.

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