Multi-scale core anisotropy percolation test experimental device and method

Abstract

The application discloses a kind of multi-scale core anisotropy percolation test experimental device and method, wherein the device includes: the core clamping module and permeability test module with hollow center made integrally, the core clamping module has fluid transport channel in different vertical horizon, different direction, the permeability test module includes multiple percolation inlet pipe, multiple percolation outlet pipe and percolation fluid metering system, percolation inlet pipe, percolation outlet pipe are respectively installed in fluid transport channel, and are communicated with percolation fluid metering system, percolation fluid metering system is used to: to multiple percolation inlet pipe transport fluid, and to multiple percolation inlet pipe, multiple percolation outlet pipe provide pressure;Real-time detection percolation inlet pipe and percolation outlet pipe pressure difference data;According to the pressure difference data, the permeability of core is calculated.The application can realize the permeability test of different horizon and different direction under conventional triaxial condition.

Description

Technical Field

[0001] This invention relates to the field of rock seepage testing technology, and in particular to a multi-scale rock core anisotropic seepage testing apparatus and method. Background Technology

[0002] This section is intended to provide background or context for the embodiments of the invention set forth in the claims. The description herein is not an admission that it is prior art simply because it is included in this section.

[0003] With the increasing depletion of conventional oil and gas development and the advancement of horizontal well and hydraulic fracturing technologies, unconventional oil and gas resources, including shale oil and gas and tight oil and gas, have entered a golden age of rapid development and are becoming an important successor for future oil and gas resource reserve and production increases. Compared with conventional reservoirs, unconventional oil and gas reservoirs exhibit more frequent changes in their composition, stronger formation heterogeneity, and significantly developed microstructures. These reservoir geological characteristics directly affect the effectiveness of unconventional oil and gas reservoirs. Among these, microstructures such as bedding and fractures significantly affect the mechanical behavior and permeability characteristics of reservoir rocks, resulting in significant anisotropy of seepage in different directions in unconventional reservoirs, thus impacting the prediction of recoverable reserves and the evaluation of production capacity in unconventional oil and gas wells.

[0004] Currently, permeability evaluation techniques for unconventional reservoir rocks under conventional triaxial conditions are relatively mature. Existing patents and equipment, such as the GCTS rock testing system and the MTS rock testing system, can perform permeability tests on reservoir rocks. However, these systems can only conduct surface-to-surface unidirectional permeation experiments, and they typically use core samples from vertical drilling during permeability measurements, thus primarily measuring permeability perpendicular to bedding planes. But for sedimentary rock reservoirs such as shale or coal, the permeability in the horizontal bedding plane is often several orders of magnitude higher than that perpendicular to bedding planes. Therefore, the test results described above do not represent the true permeability of the reservoir, and direct use of these results would severely underestimate the predicted recoverable reserves.

[0005] To address the problem of anisotropic permeability testing in unconventional reservoirs, researchers have proposed several different solutions. For example, subscale cores containing different types of microstructures are drilled from different directions within a full-diameter core, and permeability tests are performed sequentially. However, since the permeability test results obtained in different directions are not from the same sample, the results cannot reflect the permeability anisotropy of highly heterogeneous rock samples (such as shale).

[0006] In summary, the current permeability testing system based on conventional triaxial testing equipment cannot meet the testing requirements for anisotropic permeability of unconventional oil and gas reservoirs. Summary of the Invention

[0007] This invention also provides a multi-scale core anisotropic seepage testing experimental device to realize permeability testing at different layers and in different directions under conventional triaxial conditions. The device includes: a core clamping module and a permeability testing module.

[0008] The core clamping module is a hollow, integrated hardware structure used to clamp the core, and the size of the center matches the size of the core. The core clamping module has fluid transport channels in different vertical layers and directions. One end of the fluid transport channel is opened at the internal center of the core clamping module, and the other end of the fluid transport channel is opened on the external surface of the core clamping module.

[0009] The permeability testing module includes multiple inlet pipes, multiple outlet pipes, and a permeation fluid metering system;

[0010] The multiple seepage inlet pipes: one end is connected to the seepage fluid metering system, and the other end delivers fluid to the core through the fluid transport channel;

[0011] The multiple seepage pipes: one end is connected to the core via a fluid transport channel, and the other end is connected to the seepage fluid metering system;

[0012] The seepage fluid metering system is used to: deliver fluid to multiple seepage inlet pipes and provide pressure to multiple seepage inlet pipes and multiple seepage outlet pipes; detect the pressure difference data between the seepage inlet pipes and the seepage outlet pipes in real time; and calculate the permeability of the core based on the pressure difference data.

[0013] This invention provides a multi-scale core anisotropic flow testing method, wherein the method includes:

[0014] Receive seepage test path parameters; the seepage test path parameters are used to start a specified seepage inlet pipe and a specified seepage inlet pipe to realize the permeability measurement in different directions inside the core.

[0015] Obtain pressure difference data between the inlet and outlet pipes at multiple time points;

[0016] The core permeability was determined based on the pressure difference data between the inlet and outlet pipes at multiple time points.

[0017] This invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the above-described multi-scale core anisotropic seepage testing method.

[0018] This invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described multi-scale core anisotropic flow testing method.

[0019] This invention also provides a computer program product, which includes a computer program that, when executed by a processor, implements the above-described multi-scale core anisotropic seepage testing method.

[0020] The multi-scale core anisotropic seepage testing experimental device in this embodiment of the invention includes an integrally manufactured hollow core clamping module and a permeability testing module. The core clamping module has fluid transport channels in different vertical layers and directions. This embodiment of the invention can realize triaxial permeability testing on the same specimen under conventional triaxial conditions, effectively assessing the anisotropy of core seepage. The seepage test conducted by the multi-scale core anisotropic seepage testing experimental device according to this embodiment of the invention can be completed in the same experimental process without disassembling the specimen. Furthermore, the seepage test can set different fluid seepage paths, which can fully consider the development characteristics of the microstructure inside the core.

[0021] The multi-scale core anisotropic seepage testing method in this embodiment of the invention is applied to the multi-scale core anisotropic seepage testing experimental device. It can realize the testing of triaxial permeability of the same specimen under conventional triaxial conditions, effectively evaluate the anisotropy of core seepage, and set fluid seepage paths in different directions, which can fully consider the development characteristics of the microstructure inside the core. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings:

[0023] Figure 1 This is a schematic diagram of the multi-scale core anisotropic seepage testing experimental device in an embodiment of the present invention;

[0024] Figure 2 This is a schematic diagram of the seepage pad in an embodiment of the present invention;

[0025] Figure 3 This is a specific example of the multi-scale core anisotropic seepage testing experimental device in this invention.

[0026] Figure 4This is a flowchart illustrating the multi-scale core anisotropic flow testing method in an embodiment of the present invention.

[0027] Figure 5 This is a schematic diagram showing the micro-CT imaging results and internal crack development of the core sample in an embodiment of the present invention.

[0028] Figure 6 This is a schematic diagram of a computer device in an embodiment of the present invention. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Here, the illustrative embodiments of the present invention and their descriptions are used to explain the present invention, but are not intended to limit the present invention.

[0030] To address the problems existing in the prior art, this invention provides a multi-scale core anisotropic seepage testing device and method. This method can determine the permeability characteristics of rocks under different directions and seepage paths based on the microstructural features of the rock during the same experiment, achieving anisotropic evaluation of seepage in the same specimen under conventional triaxial stress.

[0031] Figure 1 This is a schematic diagram of the multi-scale core anisotropic seepage testing experimental device in an embodiment of the present invention, as shown below. Figure 1 As shown, the experimental setup includes a core clamping module 3 and a permeability testing module.

[0032] The core clamping module 3 is an integrally manufactured hardware with a hollow center, which is used to clamp the core 2. The size of the center matches the size of the core 2. The core clamping module 3 has fluid transport channels 4 at different vertical layers and in different directions. One end of the fluid transport channel 4 is opened at the internal center of the core clamping module 3, and the other end of the fluid transport channel 4 is opened on the external surface of the core clamping module 3.

[0033] The permeability testing module includes multiple inlet pipes, multiple outlet pipes, and a permeation fluid metering system;

[0034] The multiple seepage inlet pipes: one end is connected to the seepage fluid metering system, and the other end delivers fluid to the core 2 through the fluid transport channel 4;

[0035] The multiple seepage pipes: one end is connected to the core 2 through the fluid transport channel 4, and the other end is connected to the seepage fluid metering system;

[0036] The seepage fluid metering system is used to: deliver fluid to multiple seepage inlet pipes and provide pressure to multiple seepage inlet pipes and multiple seepage outlet pipes; detect the pressure difference data between the seepage inlet pipes and the seepage outlet pipes in real time; and calculate the permeability of the core based on the pressure difference data.

[0037] In one embodiment, the core clamping module 3 is manufactured by 3D printing.

[0038] like Figure 1 As shown, the core clamping module 3 is a cylindrical core clamping device with a cubic hollow center. The size of the cubic hollow center is determined by the size of the core to be tested and is used to accommodate the core specimen. The core clamping module 3 can perform permeability testing on cores of different sizes and shapes, and can meet the needs of full-scale core seepage testing.

[0039] Based on different 3D printing technology solutions, the core clamping module 3 can print different numbers of fluid transport channels inside the cylindrical core clamping device at different layers and directions, according to factors such as seepage system design, experimental objectives, and sample characteristics. It can also connect to an external permeability testing module to ensure that seepage experiments at different layers and directions can be conducted in the same experimental process, thereby improving the flexibility of experimental design.

[0040] In one embodiment, the 3D printing material for the core clamping module 3 is photosensitive resin. In practice, a special tough photosensitive resin material is selected for the 3D printing, capable of withstanding high-pressure experimental conditions.

[0041] Figure 2 This is a schematic diagram of the seepage pad in an embodiment of the present invention, as shown below. Figure 2 As shown, the multi-scale core anisotropic seepage test apparatus may also include a permeable pad 14;

[0042] The contact surface between the core clamping module 3 and the core 2 has an inwardly recessed groove for installing the permeation gasket 14.

[0043] The permeation pad 14 is in direct contact with the core 2. Multiple permeation holes and surface seepage paths are arranged inside the pad. The permeation holes pass through the permeation pad 14 and are connected to the fluid transport channel 4 inside the core clamping module 3.

[0044] The permeation gasket 14 has several permeation holes and surface seepage paths arranged inside. The permeation holes run through the permeation gasket 14 and communicate with the fluid transport channel 4 inside the core clamping module 3, ensuring that the test fluid is evenly distributed on the surface of the core 2. Adjacent permeation zones inside the permeation gasket 14 are separated from each other by a certain distance, ensuring that gas will not flow into adjacent permeation zones during unidirectional seepage.

[0045] Figure 3This is a specific example diagram of the multi-scale core anisotropic seepage testing experimental apparatus in an embodiment of the present invention, as shown below. Figure 1 , Figure 3 As shown, the core clamping module 3 contains fluid transport channels 4, which are integrally processed from high-rigidity 3D printed raw materials, at different layers and in different directions. With the external permeability testing module, seepage experiments at different layers and in different directions can be carried out in the same experimental process. Figure 3 The experimental setup for testing anisotropic seepage in cores at multiple scales includes a core holder 1, a confining pressure pump 6, valves 7, a pressure gauge 10, a differential pressure gauge 11, a venting system 12, and a vacuum system 13. The core holding module 3 is located inside the core holder 1.

[0046] The seepage fluid metering system includes a fluid injection pump 5, an upstream (downstream) gas cylinder 9, and a differential pressure gauge 11.

[0047] Each seepage inlet pipe: one end is connected to the fluid injection pump 5 via an upstream gas cylinder, and the other end delivers fluid to the core 2 via the fluid transport channel 4;

[0048] Each seepage pipe: one end is connected to the core 2 through the fluid transport channel 4, and the other end is connected to the seepage fluid metering system through the downstream gas cylinder;

[0049] The upstream gas cylinder and the downstream gas cylinder are connected by a differential pressure gauge 11, which is used to detect the pressure difference between the upstream gas cylinder and the downstream gas cylinder in real time.

[0050] The fluid injection pump 5 provides pressure to the upstream gas cylinder through the seepage inlet pipe and to the downstream gas cylinder through the seepage outlet pipe.

[0051] refer to Figure 1 , Figure 3 The permeability testing module includes multiple layers and numerous seepage inlet and outlet pipes in the X and Y directions (horizontal direction), as well as a seepage fluid metering system. The seepage inlet pipes are installed upstream of the X and Y direction seepage fluid channels into the fluid transport channels 4 pre-installed inside the core clamping module 3, and connected to several seepage holes via permeation gaskets 14. The seepage outlet pipes are connected downstream of the X and Y direction seepage fluid transport channels 4 in the same manner. The Z-direction (vertical direction) seepage pipeline setup adopts a conventional triaxial permeability testing system, which will not be discussed further here.

[0052] The seepage fluid metering system includes a fluid injection pump 5, upstream and downstream gas cylinders, and several control valves and pressure gauges 11. The fluid injection pump 5 provides pressure to the upstream (downstream) gas cylinder through pipelines, and the pressure supply process is controlled by the control valves. The test fluid in the upstream gas cylinder passes through a multi-port pneumatic valve 8, enters the core clamping module 3 in the sample chamber through the seepage inlet pipe, flows through the sample, and then flows into the downstream gas cylinder through the seepage outlet pipe and the multi-port pneumatic valve 8. Each gas cylinder is connected to a high-precision pressure gauge for real-time monitoring of the pressure in the upstream and downstream gas cylinders. The upstream and downstream gas cylinders are connected by a differential pressure gauge for real-time detection of the pressure difference between the upstream and downstream gas cylinders. The experiment is conducted under constant temperature conditions. During the seepage experiment, the core clamping module 3 and the internal sample are controlled by vertical axial pressure and horizontal confining pressure through a confining pressure pump 6.

[0053] Preferably, each inlet pipe and each outlet pipe is equipped with a valve that can be controlled individually.

[0054] Preferably, all seepage inlet and outlet pipes at the same stratum are connected to the same pipeline at the bottom of the core clamping module, and can be individually connected to upstream (downstream) gas cylinders through multi-port pneumatic valve 8.

[0055] Preferably, depending on the permeability characteristics of the sample to be tested, the number of upstream and downstream gas cylinders in the seepage fluid metering system can be set to multiple, each gas cylinder is equipped with a valve, and each can be opened or closed independently. For low-permeability / ultra-low-permeability core samples, the volume of a single upstream or downstream gas cylinder should not be too large.

[0056] Based on a multi-scale core anisotropic seepage testing experimental apparatus, this invention also provides a multi-scale core anisotropic seepage testing method. Figure 4 This is a flowchart illustrating the multi-scale core anisotropic flow testing method in an embodiment of the present invention, as shown below. Figure 4 As shown, the method includes:

[0057] Step 401: Receive seepage test path parameters; the seepage test path parameters are used to start the specified seepage inlet pipe and realize the permeability measurement in different directions inside the core.

[0058] Step 402: Obtain pressure difference data between the seepage inlet pipe and the seepage outlet pipe at multiple time points;

[0059] Step 403: Determine the core permeability based on the pressure difference data of the seepage inlet and outlet pipes at multiple time points.

[0060] When implementing this, you can follow these steps:

[0061] Step 1: Rock Sample Preparation: Using wire cutting, cubic samples of different sizes are cut from the core sample of different diameters. The surfaces are polished, and the dimensional processing error of the samples should be less than 0.1 mm to ensure the accuracy of the seepage test results. The core sample microstructure identification process utilizes imaging techniques such as X-ray CT to identify the microstructural features inside the core, including the spatial distribution characteristics of bedding and fractures. (Refer to...) Figure 5 , Figure 5 This is a schematic diagram showing the micro-CT imaging results and internal fracture development of the core sample in an embodiment of the present invention. Figure 5 The left image shows the micro-CT imaging results of the core sample to be tested in an embodiment of the present invention. Figure 5 The right side shows the spatial distribution of fracture channels inside the core sample in an embodiment of the present invention.

[0062] Step 2: Install the rock sample: Embed the rock sample prepared in Step 1 into the 3D-printed core clamping module in preparation for seepage testing.

[0063] Step 3: Set experimental conditions: Set the internal confining pressure and axial pressure of the sample chamber; set the seepage experimental path according to the spatial distribution characteristics of the microstructure inside the sample in Step 1.

[0064] Step 4: Start the experiment: Use a vacuum device to bring the sample and experimental system into a vacuum state; apply confining pressure and axial pressure to the core and core clamping device according to the experimental conditions in Step 3; determine the required number of upstream and downstream gas cylinders based on the seepage characteristics of the sample to be tested, and open the corresponding valves; inject gas into the upstream (downstream) gas cylinders using a fluid injection pump until the upstream (downstream) gas cylinders reach the predetermined pressure; open the control valves of the designated upstream and downstream seepage inlet and outlet pipes according to the seepage experimental path set in Step 3; open the pneumatic multi-port control valves between the upstream (downstream) gas cylinders and the seepage inlet and outlet pipes to allow the gas to move in the preset seepage inlet and outlet pipes; monitor and record the pressure changes and pressure difference between the upstream and downstream gas cylinders in real time.

[0065] Step 5: Experimental data analysis. Based on the upstream and downstream pressure change data collected in Step 4, calculate the permeability of the sample under the specified seepage path.

[0066] In one embodiment, the seepage test path parameters are used to determine the permeability of one of the following: surface-to-surface seepage path, layer-to-layer seepage path, and point-to-point seepage path.

[0067] The surface-to-surface seepage path means that: in the horizontal direction, each seepage inlet pipe and each seepage outlet pipe of all layers are started simultaneously, and the seepage experiment is started in the vertical direction;

[0068] The layer-to-layer seepage path means that all seepage inlet pipes and all seepage outlet pipes on a single layer are activated simultaneously in the horizontal direction.

[0069] The point-to-point seepage path means that any one or more seepage inlet pipes and seepage outlet pipes are started at any layer.

[0070] Preferably, based on the microstructural characteristics of the sample, the test fluid in the test method of this embodiment of the invention can be subjected to a seepage experiment according to the following seepage path:

[0071] ① Triaxial seepage test (surface-to-surface): By simultaneously opening the individual control valves of all seepage inlet and outlet pipes in the X (Y) direction and their pneumatic multi-port control valves connected to the upstream and downstream gas cylinders, the permeability of the core can be measured sequentially in the X, Y, and Z directions under conventional triaxial conditions and in the same experimental process.

[0072] ② Horizontal seepage experiment (layer-to-layer): By simultaneously opening the individual control valves of all seepage inlet and outlet pipes at a certain layer along the X (Y) direction, as well as the pneumatic multi-port control valves connecting that layer to the upstream and downstream gas cylinders, it is possible to measure the permeability of the core sample in the X (Y) direction under conventional triaxial conditions and during the same experimental process. This seepage path is suitable for core samples with well-developed horizontal microstructures (such as stratification).

[0073] ③ Horizontal seepage experiment (point-to-point): By opening individual control valves for one or more seepage inlet and outlet pipes at a specific stratum along the X (Y) direction, as well as pneumatic multi-port control valves connecting the stratum to which the seepage inlet and outlet pipes belong to the upstream and downstream gas cylinders, permeability measurements can be performed on any two or more points in the X (Y) direction of the core sample under conventional triaxial conditions during the same experimental process. This seepage path is suitable for core samples with well-developed fractures, and different seepage paths can be set according to the orientation and dip angle of different fractures.

[0074] During implementation, a suitable seepage path is set based on the heterogeneity of the fracture network development inside the core.

[0075] To further clarify and implement the method, in one embodiment, determining the core permeability based on pressure difference data between the seepage inlet and outlet pipes at multiple time points may include:

[0076] The permeability of the core sample under a specified seepage path is obtained by fitting the following formula:

[0077]

[0078] Among them, P u -P d P represents the pressure difference between upstream and downstream gas cylinders at multiple time points during the test. u,0 -P d,0 To test the initial pressure difference between the upstream and downstream gas cylinders, P u P dThese represent the upstream and downstream cylinder pressures at multiple time points during the test, P. u,0 P d,0 These represent the upstream and downstream gas cylinder pressures at the initial moment of the test, respectively; μ is the viscosity of the test fluid; t is time; k is permeability; L is the sample length; A is the cross-sectional area of ​​the core sample; and V is the cross-sectional area of ​​the core sample. μ and V d These represent the volumes of the upstream and downstream gas cylinders, respectively.

[0079] The embodiments of the present invention have the following advantages over the prior art: (1) The present invention can test the triaxial permeability of the same specimen under conventional triaxial conditions, and can effectively evaluate the anisotropy of core seepage; (2) The seepage test performed in the embodiments of the present invention can be completed in the same experimental process without disassembling the specimen; (3) The seepage test performed in the embodiments of the present invention can be performed on cubic cores of different sizes; (4) The seepage test performed in the embodiments of the present invention can set different fluid seepage paths (surface-to-surface, layer-to-layer, point-to-point), which can fully consider the development characteristics of the microstructure inside the core.

[0080] Figure 6 This is a schematic diagram of a computer device in an embodiment of the present invention, such as... Figure 6 As shown, this embodiment of the invention also provides a computer device 600, including a processor 601, a memory 602, and a computer program 603 stored in the memory 602 and executable on the processor 601. When the processor 601 executes the computer program 603, it implements the above-mentioned multi-scale core anisotropic seepage test method.

[0081] This invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described multi-scale core anisotropic flow testing method.

[0082] This invention also provides a computer program product, which includes a computer program that, when executed by a processor, implements the above-described multi-scale core anisotropic seepage testing method.

[0083] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0084] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0085] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0086] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0087] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A multi-scale core anisotropic seepage testing experimental apparatus, characterized in that, include: Core clamping module, permeability testing module; The core clamping module is a hollow, integrated hardware structure used to clamp the core, and the size of the center matches the size of the core. The core clamping module has fluid transport channels in different vertical layers and directions. One end of the fluid transport channel is opened at the internal center of the core clamping module, and the other end of the fluid transport channel is opened on the external surface of the core clamping module. The permeability testing module includes multiple inlet pipes, multiple outlet pipes, and a permeation fluid metering system; The multiple seepage inlet pipes: one end is connected to the seepage fluid metering system, and the other end delivers fluid to the core through the fluid transport channel; The multiple seepage pipes: one end is connected to the core via a fluid transport channel, and the other end is connected to the seepage fluid metering system; The seepage fluid metering system is used to: deliver fluid to multiple seepage inlet pipes and provide pressure to multiple seepage inlet pipes and multiple seepage outlet pipes; detect the pressure difference data between the seepage inlet pipes and the seepage outlet pipes in real time; and calculate the permeability of the core based on the pressure difference data.

2. The multi-scale core anisotropic seepage testing experimental apparatus as described in claim 1, characterized in that, The core clamping module is manufactured using 3D printing.

3. The multi-scale core anisotropic seepage testing experimental apparatus as described in claim 2, characterized in that, The 3D printing material for the core clamping module is photosensitive resin.

4. The multi-scale core anisotropic seepage testing experimental apparatus as described in claim 1, characterized in that, It also includes permeable pads; The core clamping module has an inwardly recessed groove on its contact surface with the core, which is used to install a permeable gasket. The permeation pad is in direct contact with the rock core and has multiple permeation holes and surface seepage paths arranged inside. The permeation holes penetrate the permeation pad from front to back and are connected to the fluid transport channels inside the rock core clamping module.

5. The multi-scale core anisotropic seepage testing experimental apparatus as described in claim 1, characterized in that, The pressure difference data between the seepage inlet pipe and the seepage outlet pipe includes the pressure difference between the upstream gas cylinder and the downstream gas cylinder; The seepage fluid metering system includes a fluid injection pump, an upstream gas cylinder, a downstream gas cylinder, and a differential pressure gauge; Each seepage inlet pipe: one end is connected to the fluid injection pump via an upstream gas cylinder, and the other end delivers fluid to the core via a fluid transport channel; Each seepage pipe: one end is connected to the core via a fluid transport channel, and the other end is connected to the seepage fluid metering system via a downstream gas cylinder; The upstream gas cylinder and the downstream gas cylinder are connected by a differential pressure gauge, which is used to detect the pressure difference between the upstream gas cylinder and the downstream gas cylinder in real time. The fluid injection pump: provides pressure to the upstream gas cylinder through the seepage inlet pipe and to the downstream gas cylinder through the seepage outlet pipe.

6. The multi-scale core anisotropic seepage testing experimental apparatus as described in claim 5, characterized in that, Each inlet and outlet pipe is equipped with a valve that can be controlled individually.

7. The multi-scale core anisotropic seepage testing experimental apparatus as described in claim 5, characterized in that, All seepage inlet and outlet pipes at the same stratum are connected to the same pipeline at the bottom of the core clamping module.

8. A multi-scale core anisotropic flow testing method, characterized in that, The method, using the multi-scale core anisotropic seepage testing apparatus according to any one of claims 1 to 7, comprises: Receive seepage test path parameters; the seepage test path parameters are used to start a specified seepage inlet pipe and a specified seepage inlet pipe to realize the permeability measurement in different directions inside the core. Obtain pressure difference data between the inlet and outlet pipes at multiple time points; The core permeability was determined based on the pressure difference data between the inlet and outlet pipes at multiple time points.

9. The multi-scale core anisotropic flow testing method as described in claim 8, characterized in that, The seepage test path parameters are used to determine the permeability of one of the following: surface-to-surface seepage path, layer-to-layer seepage path, and point-to-point seepage path. The surface-to-surface seepage path means that: in the horizontal direction, each seepage inlet pipe and each seepage outlet pipe of all layers are started simultaneously, and the seepage experiment is started in the vertical direction; The layer-to-layer seepage path means that all seepage inlet pipes and all seepage outlet pipes on a single layer are activated simultaneously in the horizontal direction. The point-to-point seepage path means that any one or more seepage inlet pipes and seepage outlet pipes are started at any layer.

10. The multi-scale core anisotropic flow testing method as described in claim 8, characterized in that, Based on the pressure difference data between the inlet and outlet pipes at multiple time points, the core permeability was determined, including: The permeability of the core sample under a specified seepage path is obtained by fitting the following formula: Among them, P u -P d P represents the pressure difference between upstream and downstream gas cylinders at multiple time points during the test. u,0 -P d,0 To test the initial pressure difference between the upstream and downstream gas cylinders, P u P d These represent the upstream and downstream cylinder pressures at multiple time points during the test, P. u,0 P d,0 These represent the upstream and downstream gas cylinder pressures at the initial moment of the test, respectively; μ is the viscosity of the test fluid; t is time; k is permeability; L is the sample length; A is the cross-sectional area of ​​the core sample; and V is the cross-sectional area of ​​the core sample. μ and V d These represent the volumes of the upstream and downstream gas cylinders, respectively.

11. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the method of any one of claims 8 to 10.

12. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the method of any one of claims 8 to 10.

13. A computer program product, characterized in that, The computer program product includes a computer program that, when executed by a processor, implements the method of any one of claims 8 to 10.

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