A numerical simulation-based radiation well pumping test method and device

Abstract

The application provides a radiation well pumping test method and device based on numerical simulation, and solves the technical problem that the prior art cannot accurately determine hydrogeological parameters and evaluate the water yield of a radiation well to form a scientific basis for groundwater resource management and decision-making. The method comprises the following steps: setting a water level observation hole according to obtained geological basic data; collecting observation data during a single large drawdown pumping process; preliminarily constructing a hydrogeological model according to the geological basic data; forming a radiation well geological model according to the hydrogeological model; and performing radiation well numerical simulation to form hydrogeological parameter calibration according to the radiation well geological model and the observation data. The large drawdown pumping is used, and a numerical model is used to depict the radiation well structure. Compared with a conventional pumping test, only one drawdown pumping is performed, and the method has the advantages of short cycle and low cost; the numerical model is used to depict the radiation well structure, the local seepage field effect of the horizontal pipe of the radiation well is considered, and the calibrated hydrogeological parameters are more accurate.

Description

Technical Field

[0001] This invention relates to the field of pumping test technology, specifically to a method and apparatus for pumping tests of radial wells based on numerical simulation. Background Technology

[0002] Radial wells are a special type of well widely used in shallow groundwater extraction. They consist of a large-diameter vertical shaft and several to dozens of horizontal collection pipes (horizontal radial pipes) driven horizontally from within the shaft. The combination of the main shaft and radial branch pipes (radial pipes) expands the drainage area, significantly increasing the single-well output. Pumping tests are a core method for evaluating the output of radial wells, analyzing aquifer hydrogeological parameters, and predicting groundwater resources. This mainly involves drilling and pumping water, measuring data such as pumping volume, water level, and water level changes over time in observation wells. Based on the steady-flow or unsteady-flow theory of well and borehole inflow, numerical simulations are performed using a function of pumping volume and drawdown to quantify aquifer permeability parameters—an in-situ permeability test process. However, traditional pumping test methods for radial wells have the following limitations:

[0003] 1. The special structural characteristics of radial wells cannot be fully considered.

[0004] Radial wells consist of a main well and multiple horizontal radial conduits, a structure that significantly alters the distribution of the groundwater flow field. Traditional pumping test specifications are typically designed for single-well or multi-well systems, failing to adequately consider the impact of the horizontal conduits of radial wells on the aquifer. This results in test results that are difficult to reflect the actual pumping capacity of radial wells and the dynamic changes in the groundwater flow field.

[0005] 2. The parameter inversion method has shortcomings.

[0006] Existing pumping test specifications typically employ traditional hydraulic parameter calculation methods (such as the Theis formula and the Jacob formula). Analytical models based on steady-flow or unsteady-flow theories (such as the Theis formula) require strict assumptions about homogeneous and isotropic aquifers. These methods, based on idealized mathematical models, struggle to handle the unique structure of radial wells. They often simplify assumptions about radial wells using existing empirical formulas (such as the equivalent large-diameter well method and the Bolton method), neglecting the seepage characteristics of horizontal radial pipes and the dynamic changes of three-dimensional unsteady flow. They fail to consider the local seepage field effects of the horizontal pipes in radial wells, making it difficult to accurately simulate unsteady seepage fields and the complex seepage behavior of radial wells. Furthermore, they fail to reflect the influence of the complex structure of radial wells (such as the length and angle distribution of radial pipes) on the seepage field. This leads to significant parameter inversion errors, limiting the accuracy and applicability of the test results.

[0007] 3. The testing cycle is long and the efficiency is low.

[0008] Radial well pumping tests typically require a lengthy pumping process to observe dynamic changes in water level, especially under complex geological conditions, where the test cycle may be further extended. This necessitates extensive on-site pumping and prolonged monitoring of water level and flow data, which is time-consuming and limited by site conditions, making it difficult to obtain results quickly. This not only increases the cost of the test but also delays the application of the results.

[0009] The aforementioned shortcomings inevitably lead to the inability of existing numerical simulation processes to obtain reliable observational data and data dimensions, resulting in significant deficiencies in data accuracy, data distribution, and data volume. This prevents the formation of a model structure that reflects actual geological conditions. Therefore, proposing a scientific and reasonable pumping test method is of significant practical importance for guiding the implementation of radial wells, determining hydrogeological parameters, evaluating their water output, and providing a basis for water resource management. Summary of the Invention

[0010] In view of the above problems, embodiments of the present invention provide a method and apparatus for radial well pumping tests based on numerical simulation, which solves the technical problem that the existing technology cannot accurately determine hydrogeological parameters and evaluate the water output of radial wells to provide a scientific basis for groundwater resource management and decision-making.

[0011] The numerical simulation-based radial well pumping test method of this invention includes:

[0012] Water level observation wells were set up based on the acquired geological data;

[0013] Data collection was conducted during a single deep drawdown pumping process.

[0014] A preliminary hydrogeological model was constructed based on basic geological data;

[0015] Geological models of radial wells were developed based on hydrogeological models.

[0016] Hydrogeological parameters were calibrated by numerical simulation of the radial well based on the geological model and observation data.

[0017] In one embodiment of the present invention, the geological basic data includes lithological data of the strata in which the site is located, regional hydrogeological survey results, and surrounding strata data;

[0018] In one embodiment of the present invention, the strategy for deploying the water level observation wells includes:

[0019] - Update stratigraphic and lithological information during deployment;

[0020] - The observation wells were flushed to restore the natural permeability of the aquifer;

[0021] -Based on the results of regional hydrogeological surveys, directional selection is made, including:

[0022] For homogeneous isotropic aquifers: vertical to the groundwater flow direction, one observation line is arranged when the hydraulic gradient is small, and two observation lines are arranged vertically and parallel to the flow direction when the hydraulic gradient is large.

[0023] For homogeneous anisotropic aquifers: observation lines are arranged along different reservoir and water-conducting properties to obtain hydrogeological parameters in each direction;

[0024] For boundary condition exploration: If it is necessary to determine the aquifer boundary, the observation line should be arranged perpendicular to the boundary, and observation holes should be set on both sides of the boundary;

[0025] Regarding the number of observation wells: at least 3 observation wells should be set up for each observation line to form a water level drawdown curve;

[0026] - The settings for the spacing and position of the observation holes include:

[0027] First well distance: The distance between the first observation well and the main well should avoid the influence of three-dimensional flow and should not be less than the aquifer thickness;

[0028] Subsequent spacing: The spacing between subsequent observation wells must ensure the difference in drawdown, and the drawdown of the farthest observation well must be greater than 20cm, and the water level difference between adjacent wells must be greater than 20cm;

[0029] Observation hole structure and depth: All observation hole filters should be of equal length and placed in the same aquifer and at the same depth. The depth of the observation hole should penetrate the target aquifer.

[0030] In one embodiment of the present invention, the observation data acquisition process includes:

[0031] - Record the initial static water level of the main wellbore and observation wells;

[0032] - Record the influencing factors before the start of large-depth pumping, including weather, temperature and surrounding pumping activities;

[0033] - Continuous observation data collection using automated observation equipment;

[0034] - This forms a large drawdown and pumping-recovery process. For unconfined aquifers, the design drawdown exceeds 1 / 2 of the aquifer thickness. For confined aquifers, the design drawdown is the confined head.

[0035] - After pumping to a lower depth, stop pumping until the water level is restored. During the pumping-restoration process, simultaneously monitor the water level and volume of the main well and surrounding observation wells.

[0036] In one embodiment of the present invention, the automatic observation device includes a pressure sensor for observing the water level in the main well and the observation well, an ultrasonic flow meter for measuring the pumping volume in the main well, and the water level and volume recording frequency is 1 minute / time.

[0037] In one embodiment of the present invention, the observation data is aggregated to a host storage device via a communication link, and the host computing device quantifies key parameters of the groundwater flow field. These key parameters include:

[0038] Water head (water level): The potential energy that reflects the direction of groundwater flow. In unconfined aquifers, the term "groundwater level" is commonly used, while in confined aquifers, the term "piezometric head" is used.

[0039] Hydraulic gradient (J): The difference in water head per unit distance, which is the driving force for water flow. The larger the gradient, the higher the flow velocity is usually.

[0040] Permeability coefficient (K): Reflects the water permeability of an aquifer, is closely related to lithology, and directly affects the flow velocity;

[0041] Seepage velocity (v): The actual speed at which groundwater moves through pores.

[0042] In one embodiment of the present invention, the step of forming a geological model of a radial well based on a hydrogeological model includes:

[0043] The basic framework of the geological environment of the radial well is obtained through a hydrogeological model, and the geological bodies around the well (strata, aquifers, impermeable layers, structures, etc.) are digitally characterized.

[0044] -Establish stratigraphic stratification and lithological distribution to provide a stratification basis for subsequent parameter assignment and well body characterization;

[0045] -Establish hydrogeological structure, identify aquifers, impermeable layers (and special structures), and clarify the differences in permeability of aquifers;

[0046] - Establish the model scale and accuracy, taking into account both "macro-regional" and "local fine" aspects. The regional scale reflects the impact of the radial well on the surrounding groundwater system, while the local scale reflects the micro-hydraulic connection between the horizontal radial pipe and the surrounding strata.

[0047] - The Multilayer Well boundary conditions in Boundary Conditions (BC) are used to characterize the water exchange between the main well and different formations. The total flow of the main well is decomposed into the contribution of each layer, which is directly coupled with the layered structure of the three-dimensional geological model to set its specific water outlet location and well diameter.

[0048] - Discrete features are used to characterize the horizontal radial tube (laterally extending water collection tube) of the radial well and the local strong seepage zone formed by discrete structures in the formation, so as to reflect the characteristics of spatial discontinuity and significant differences in seepage characteristics from the surrounding formation.

[0049] - The permeability coefficient (K) is set in conjunction with the spatial distribution in the 3D model and the geological model, Multilayer Well, and Discrete Features to describe the water permeability of the rock and soil mass.

[0050] In one embodiment of the present invention, the parameter calibration process employs linear fitting or deep learning.

[0051] The numerical simulation-based radial well pumping test apparatus of this invention includes:

[0052] The memory is used to store the program code in the process of the numerical simulation-based radial well pumping test method described above.

[0053] A processor for executing the program code.

[0054] The numerical simulation-based radial well pumping test apparatus of this invention includes:

[0055] The basic data receiving module is used to set up water level observation wells based on the acquired geological basic data;

[0056] The observation data planning module is used to collect observation data during a single large drawdown pumping process.

[0057] The geological model initial construction module is used to initially construct a hydrogeological model based on basic geological data.

[0058] The well model construction module is used to generate radial well geological models based on hydrogeological models.

[0059] The well type parameter calibration module is used to calibrate hydrogeological parameters by performing numerical simulations of radial wells based on the geological model and observation data of the radial wells.

[0060] The numerical simulation-based radial well pumping test method and apparatus of this invention can determine hydrogeological parameters and evaluate the water output of radial wells. It utilizes large drawdown pumping and employs a numerical model to characterize the radial well structure. Compared to conventional pumping tests, it only requires pumping at one drawdown, offering advantages such as shorter cycle time and lower cost. Furthermore, by using a numerical model to characterize the radial well structure, the local seepage field effect of the horizontal pipe in the radial well is considered, resulting in more accurate calibration of the hydrogeological parameters. Attached Figure Description

[0061] Figure 1 The diagram shown is a flowchart of a numerical simulation-based method for pumping water from a radial well, according to an embodiment of the present invention.

[0062] Figure 2 The diagram shown is a schematic representation of the architecture of a radial well pumping test device based on numerical simulation according to an embodiment of the present invention. Detailed Implementation

[0063] To make the objectives, technical solutions, and advantages of this invention clearer and more understandable, the invention will be further described below in conjunction with the accompanying drawings and specific embodiments. Obviously, the described embodiments are merely some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0064] An embodiment of the present invention provides a method for conducting a radial well pumping test based on numerical simulation, as follows: Figure 1 As shown. In Figure 1 In this embodiment, the following are included:

[0065] Step 100: Set up water level observation wells based on the acquired geological data.

[0066] Those skilled in the art will understand that the formation of radial wells depends on the geological structure and well type. Basic geological data includes, but is not limited to, lithological data of the strata, regional hydrogeological survey results, and data of surrounding strata.

[0067] Stratigraphic lithological data include, but are not limited to, the material composition, structure, physical properties, chemical properties, and spatial distribution characteristics of strata.

[0068] Based on geological data, water level observation wells are strategically deployed to enable dynamic monitoring of the groundwater flow field (such as water level, water quality, and water temperature).

[0069] Deployment strategies include, but are not limited to, selecting direction, spacing, location, depth, and quantity based on hydrogeological survey results.

[0070] In one embodiment of the present invention, the deployment strategy includes:

[0071] - Update stratigraphic lithology information during deployment.

[0072] - The observation wells are flushed to restore the natural permeability of the aquifer, ensuring the accuracy and representativeness of the observation data (such as water level, water quality, permeability coefficient, etc.).

[0073] -Based on the results of regional hydrogeological surveys, directional selection is made, including:

[0074] For homogeneous isotropic aquifers: arrange one observation line perpendicular to the groundwater flow direction (when the hydraulic gradient is small) or arrange two observation lines perpendicular to and parallel to the flow direction (when the hydraulic gradient is large).

[0075] For homogeneous anisotropic aquifers: observation lines are arranged along different directions of water storage and conduction properties to obtain hydrogeological parameters in each direction.

[0076] For boundary condition exploration: If it is necessary to determine the aquifer boundary, the observation line should be arranged perpendicular to the boundary, and observation holes should be set on both sides of the boundary.

[0077] Regarding the number of observation wells: It is advisable to set up 3 observation wells for each observation line to form a representative water level drop curve.

[0078] - The settings for the spacing and position of the observation holes include:

[0079] First well distance: The distance between the first observation well and the main well should avoid the influence of three-dimensional flow and should generally not be less than the aquifer thickness (at least >10m).

[0080] Subsequent spacing: The spacing between subsequent observation wells should ensure that the difference in drawdown is significant. For example, the farthest observation well should ensure a drawdown of >20cm and a water level difference of >20cm between adjacent wells.

[0081] Well structure and depth: All well filters should be of equal length and placed at the same aquifer and depth to ensure data comparability. A double-layered nylon mesh should be installed on the outer layer of the filter tube to prevent sediment from entering. The well depth must penetrate the target aquifer to accurately reflect aquifer level changes.

[0082] Step 200: Collect observation data during a single large drawdown pumping process.

[0083] The temporal consistency of observational data is obtained by leveraging the temporal continuity of the deep drawdown pumping process. Strategic deployment of observation wells enables the acquisition of comprehensive observational data on the recovery process of water volume decline in underground unconfined aquifers.

[0084] In one embodiment of the present invention, the observation data acquisition process includes:

[0085] Record the initial static water level of the main wellbore and observation wells.

[0086] - Record the influencing factors before the start of the large-depth pumping, including but not limited to weather, temperature, surrounding pumping activities, and other factors that may affect the water level.

[0087] - Continuous data collection is performed after the pumping facility is started using automatic monitoring equipment, including pressure sensors for water level monitoring in the main well and observation wells, and ultrasonic flow meters for measuring the pumping volume in the main well. The monitoring data is aggregated to a host storage device via a communication link. In one embodiment of the invention, the water level and volume recording frequency is once per minute.

[0088] A large drawdown pumping-recovery process is initiated, where the design drawdown for unconfined aquifers exceeds half the aquifer thickness, and for confined aquifers, the pumping head is determined. After one drawdown pumping cycle, the pumping continues until the water level is restored. During the pumping-recovery process, the water level and flow rate in the main well and surrounding observation wells are simultaneously monitored. The differences in structure and hydrodynamic characteristics between unconfined and confined aquifers are utilized to obtain the response differences during large drawdown pumping.

[0089] -The upper-level computing equipment can quantify key parameters of the groundwater flow field based on observation data. These key parameters include, but are not limited to:

[0090] Water head (water level): The potential energy that reflects the direction of groundwater flow. In unconfined aquifers, the term "groundwater level" is commonly used, while in confined aquifers, the term "piezometric head" is used.

[0091] Hydraulic gradient (J): The difference in water head per unit distance, which is the driving force for water flow. The larger the gradient, the higher the flow velocity is usually.

[0092] Permeability coefficient (K): Reflects the water permeability of an aquifer, is closely related to lithology, and directly affects the flow velocity.

[0093] Seepage velocity (v): The actual speed at which groundwater moves through pores.

[0094] Step 300: Construct a preliminary hydrogeological model based on basic geological data.

[0095] Based on the hydrogeological numerical simulation technique (involving modeling of complex aquifer structures) commonly used by those skilled in the art, the key characteristics of the groundwater system in the region are abstracted and simplified according to prior data and basic geological data, constructing a model framework that reflects its essential laws. Then, following an iterative technical path of "data collection - conceptualization - mathematical expression - verification and optimization," the collected basic geological data is analyzed to identify aquifer characteristics, define boundary conditions, determine hydrological processes, and thus improve the model structure.

[0096] Step 400: Generate a geological model of the radial well based on the hydrogeological model.

[0097] Radial well design typically involves, but is not limited to, structural information such as the diameter and depth of the vertical shaft, the diameter of the horizontal radial tubes, the distribution, length, number of layers, angles, and quantity of filter holes. The construction of radial wells also involves the surrounding groundwater and geological environment.

[0098] In one embodiment of the present invention, a basic framework of the geological environment of a radial well is obtained through a hydrogeological model, and the surrounding geological bodies (strata, aquifers, impermeable layers, structures, etc.) are digitally characterized to construct the spatial boundary and material basis of water flow. This includes:

[0099] - Establish stratigraphic stratification and lithological distribution to provide a stratification basis for subsequent parameter assignment (such as permeability coefficient) and well body characterization.

[0100] - Establish hydrogeological structures, identify aquifers (water-rich layers), impermeable layers (weakly permeable layers), and special structures (such as faults and fracture zones), and clarify the differences in the permeability of aquifers.

[0101] - Establish model scale and accuracy, taking into account both "macro-regional" and "local fine" aspects. Regional scale (e.g., 1km×1km) reflects the impact of the radial well on the surrounding groundwater system, while local scale (e.g., within a 50m radius around the well) refines the grid to characterize the micro-hydraulic connection between the horizontal radial tube and the surrounding strata.

[0102] In one embodiment of the present invention, the main well (vertical well) of the radial well typically penetrates multiple aquifers or formations (such as simultaneously connecting unconfined and confined layers). The Multilayer Well boundary condition in Boundary Conditions (BC) is used to characterize the water exchange between the main well and different formations. The total flow of the main well is decomposed into the contribution of each layer and directly coupled with the layered structure of the three-dimensional geological model to set its specific water outlet location and well diameter.

[0103] In one embodiment of the present invention, the horizontal radial pipe (laterally extending water collection pipe) of the radial well and the discrete structures in the formation (such as fractures and faults) constitute a localized area of ​​strong seepage. Discrete features are used to characterize this area, reflecting its spatial discontinuity and significant differences in seepage characteristics compared to the surrounding formation. This overcomes the shortcomings of traditional continuous medium models in accurately describing this phenomenon. The cross-sectional area of ​​the horizontal radial pipe is set according to the actual situation.

[0104] In one embodiment of the present invention, the spatial distribution of the permeability coefficient (K) in the three-dimensional model needs to be set in conjunction with the geological model, Multilayer Well, and Discrete Features to describe the water permeability of the rock and soil mass, directly determining the water collection efficiency and seepage field morphology of the radial well. A large value should be chosen, initially set at 100,000 m / d.

[0105] Step 500: Perform numerical simulation of the radiation well based on the geological model and observation data to calibrate the hydrogeological parameters.

[0106] The parameter calibration of the geological model for a radial well involves adjusting the model's calculation parameters by comparing them with actual measurement records, and then repeatedly verifying the simulation results. The steps are as follows:

[0107] Initial conditions and relevant calculation parameters are input into the geological model of the radial well for the first calculation.

[0108] After the initial calculation, the calculated groundwater level change trend is fitted with the observation data, and the error between the two is compared. If the error is large, it means that the model does not conform to the actual situation. It is necessary to continuously adjust the model parameters and boundaries and repeatedly try to make the calculated water head value as close as possible to the observed water head value, and the error between the two does not exceed the allowable range (10%).

[0109] The model, after calibration and verification, that closely matches the actual groundwater conditions in the work area can be used for further development and utilization analysis. Based on the design drawdown, the water output of the radial wells can be reasonably determined. The hydrogeological parameters obtained from the calibration are the results of the pumping tests.

[0110] In one embodiment of the present invention, the calibration fitting process adopts linear fitting, which establishes a linear relationship between the groundwater level or hydrogeological structure output by the model and the observation data through parameter linearization, quantifies the correlation deviation through linear fitting, and then reverse-engineers the optimal model parameters, including but not limited to the permeability coefficient, water exchange between the main well and different strata, velocity vector of local strong seepage zone, seepage velocity, etc.

[0111] In one embodiment of the present invention, the calibration and fitting process employs deep learning, utilizing a neural network model to simulate the working process and state of the radial well geological model. Training and testing datasets are formed using observational data. The neural network model is trained using the training dataset, and the model parameters (weights and biases) are continuously adjusted based on the data to make its predictions as close as possible to the true values. The entire process can be divided into the following four steps:

[0112] 1. Forward Propagation

[0113] Input data is passed from the input layer to the output layer, undergoes linear transformation and activation function, and finally yields the predicted value.

[0114] 2. Loss Calculation

[0115] The difference between the predicted value and the true label is calculated using a loss function.

[0116] 3. Backpropagation

[0117] According to the chain rule, the gradient of the loss with respect to each parameter is calculated layer by layer from the output layer to the input layer.

[0118] 4. Parameter Update

[0119] Use optimizers (such as SGD, Adam) to update model parameters based on gradients to reduce loss.

[0120] The numerical simulation-based radial well pumping test method of this invention can determine hydrogeological parameters and evaluate the water output of radial wells. It utilizes large drawdown pumping and employs a numerical model to characterize the radial well structure. Compared to conventional pumping tests, it only requires pumping at one drawdown, offering advantages such as shorter cycle time and lower cost. Furthermore, by using a numerical model to characterize the radial well structure, the local seepage field effect of the horizontal pipe in the radial well is considered, resulting in more accurate calibration of the hydrogeological parameters.

[0121] An embodiment of the present invention provides a radial well pumping test apparatus based on numerical simulation, comprising:

[0122] The memory is used to store the program code in the processing of the radial well pumping test method based on numerical simulation in the above embodiments;

[0123] The processor is used to execute program code in the processing of the numerical simulation-based radial well pumping test method described in the above embodiments.

[0124] The filter processor can be a DSP (Digital Signal Processor), an FPGA (Field-Programmable Gate Array), an MCU (Microcontroller Unit) system board, a SoC (System on a Chip) system board, a PLC (Programmable Logic Controller) minimum system including I / O, or cloud computing power.

[0125] An embodiment of the present invention provides a radiation well pumping test device based on numerical simulation, as follows: Figure 2 As shown. In Figure 2 In this embodiment, the following are included:

[0126] The basic data receiving module 10 is used to set up water level observation wells based on the acquired geological basic data;

[0127] The observation data planning module 20 is used to collect observation data during a single large drawdown pumping process.

[0128] Geological model initial construction module 30 is used to initially construct a hydrogeological model based on basic geological data;

[0129] Well model construction module 40 is used to form a radial well geological model based on the hydrogeological model;

[0130] Well type parameter calibration module 50 is used to calibrate hydrogeological parameters by performing numerical simulation of the radial well based on the radial well geological model and observation data.

[0131] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for conducting radial well pumping tests based on numerical simulation, characterized in that, include: Water level observation wells were set up based on the acquired geological data; Data collection is conducted during a single large drawdown pumping process. The large drawdown is defined as a drawdown exceeding 1 / 2 of the aquifer thickness for unconfined aquifers and as the confined head for confined aquifers. A preliminary hydrogeological model was constructed based on basic geological data; The main well of the radial well is characterized by the boundary condition of the multilayer well, the horizontal radial tubes of the radial well are characterized by the discrete feature, and the geological model of the radial well is completed based on the hydrogeological model. Hydrogeological parameters were calibrated by numerical simulation of the radial well based on the geological model and observation data.

2. The method for radial well pumping tests based on numerical simulation as described in claim 1, characterized in that, The geological data includes lithological data of the strata, regional hydrogeological survey results, and data of surrounding strata.

3. The method for radial well pumping tests based on numerical simulation as described in claim 1, characterized in that, The strategy for deploying the water level observation wells includes: - Update stratigraphic and lithological information during deployment; - The observation wells were flushed to restore the natural permeability of the aquifer; -Based on the results of regional hydrogeological surveys, directional selection is made, including: For homogeneous isotropic aquifers: vertical to the groundwater flow direction, one observation line is arranged when the hydraulic gradient is small, and two observation lines are arranged vertically and parallel to the flow direction when the hydraulic gradient is large. For homogeneous anisotropic aquifers: observation lines are arranged along different reservoir and water-conducting properties to obtain hydrogeological parameters in each direction; For boundary condition exploration: If it is necessary to determine the aquifer boundary, the observation line should be arranged perpendicular to the boundary, and observation holes should be set on both sides of the boundary; Regarding the number of observation wells: at least 3 observation wells should be set up for each observation line to form a water level drawdown curve; - The settings for the spacing and position of the observation holes include: First well distance: The distance between the first observation well and the main well hole should avoid the influence of three-dimensional flow, be no less than the aquifer thickness and at least >10m; Subsequent spacing: The spacing between subsequent observation wells must ensure the difference in drawdown, and the drawdown of the farthest observation well must be greater than 20cm, and the water level difference between adjacent wells must be greater than 20cm; Observation hole structure and depth: All observation hole filters should be of equal length and placed in the same aquifer and at the same depth. The depth of the observation hole should penetrate the target aquifer.

4. The method for radial well pumping tests based on numerical simulation as described in claim 1, characterized in that, The observation data acquisition process includes: - Record the initial static water level of the main wellbore and observation wells; - Record the influencing factors before the start of large-depth pumping, including weather, temperature and surrounding pumping activities; - Continuous observation data collection using automated observation equipment; - This forms a large drawdown pumping-recovery process. For unconfined aquifers, the design drawdown exceeds 1 / 2 of the aquifer thickness, and for confined aquifers, the design drawdown is the confined head. - After pumping to a lower depth, stop pumping until the initial static water level is restored. During the pumping-restoration process, simultaneously monitor the water level and volume of the main well and surrounding observation wells.

5. The method for conducting radial well pumping tests based on numerical simulation as described in claim 4, characterized in that, The automatic observation equipment includes a pressure sensor for observing the water level in the main well and observation wells, and an ultrasonic flow meter for measuring the pumping volume in the main well. The water level and volume recording frequency is 1 time per minute.

6. The method for radial well pumping tests based on numerical simulation as described in claim 4, characterized in that, The observation data is aggregated to a higher-level storage device via a communication link, and then used by a higher-level computing device to quantify key parameters of the groundwater flow field. These key parameters include: Water level: The potential energy that reflects the direction of groundwater flow. It is represented by the groundwater level in unconfined aquifers and by the piezometric head in confined aquifers. Hydraulic gradient (J): The difference in water head per unit distance, which is the driving force for water flow. The larger the gradient, the higher the flow velocity is usually. Permeability coefficient (K): Reflects the water permeability of an aquifer, is closely related to lithology, and directly affects the flow velocity; Seepage velocity (v): The actual speed at which groundwater moves through pores.

7. The method for radial well pumping tests based on numerical simulation as described in claim 1, characterized in that, The formation of the radial well geological model based on the hydrogeological model includes: The basic framework of the geological environment of the radial well is obtained through a hydrogeological model, and the geological bodies around the well are digitally characterized. -Establish stratigraphic stratification and lithological distribution to provide a stratification basis for subsequent parameter assignment and well body characterization; -Establish hydrogeological structure and identify aquifers and impermeable layers; - Establish the model scale and accuracy, taking into account both macro-regional and local fine-grained aspects. The regional scale reflects the impact of the radial well on the surrounding groundwater system, while the local scale reflects the micro-hydraulic connection between the horizontal radial tube and the surrounding strata. - The boundary conditions of the multilayer well are used to characterize the water exchange between the main well and different formations. The total flow of the main well is decomposed into the contribution of each layer and directly coupled with the layered structure of the three-dimensional geological model to set its specific water outlet location and well diameter. - Discrete features are used to characterize the horizontal radial tubes of the radial well and the local strong seepage zone formed by discrete structures in the formation, so as to reflect the characteristics of spatial discontinuity and significant differences in seepage characteristics from the surrounding formation. - The permeability coefficient (K) is set collaboratively with the spatial distribution in the 3D model, the geological model, the multilayer well, and the discrete features to describe the water permeability of the rock and soil mass.

8. The method for radial well pumping tests based on numerical simulation as described in claim 1, characterized in that, The parameter calibration process employs linear fitting or deep learning.

9. A radial well pumping test device based on numerical simulation, characterized in that, include: A memory for storing program code in the processing of the numerical simulation-based radial well pumping test method as described in any one of claims 1 to 8; A processor for executing the program code.

10. A radial well pumping test device based on numerical simulation, characterized in that, include: The basic data receiving module is used to set up water level observation wells based on the acquired geological basic data; The observation data planning module is used to collect observation data during a single large drawdown pumping process. The large drawdown is defined as a drawdown exceeding 1 / 2 of the aquifer thickness for unconfined aquifers and as the confined head for confined aquifers. The geological model initial construction module is used to initially construct a hydrogeological model based on basic geological data. The well model construction module is used to characterize the main well of the radial well using multilayer well boundary conditions, to characterize the horizontal radial tubes of the radial well using discrete features, and to form a geological model of the radial well based on the hydrogeological model. The well type parameter calibration module is used to calibrate hydrogeological parameters by performing numerical simulations of radial wells based on the geological model and observation data of the radial wells.

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