High-energy light-electricity-force combined fracturing anti-reflection test device and method

Abstract

The invention discloses a high-energy light-electricity-force combined fracturing anti-reflection test device and method, and the test device comprises a cuboid test piece which is a coal rock sample; the loading pressing plates are arranged in the left direction, the upper direction and the front direction of the cuboid test piece respectively, a fracturing groove and a sensor groove are formed in the ends, making contact with the cuboid test piece, of the loading pressing plates, and a sliding rail is installed at the top of the fracturing groove and used for being connected with the fracturing module; the fracturing module comprises a drill rod, a cable chamber and a high-pressure water chamber are arranged in the drill rod, and the cable chamber is used for laying a laser cable and an electric pulse cable; the laser cable is respectively connected with a laser probe on the outer wall of the drill rod and an external laser generator; the electric pulse cable is respectively connected with an electric pulse probe on the outer wall of the drill rod and an external discharge capacitor, and the electric pulse probe is respectively provided with a positive electrode and a negative electrode. The device can be carried out under indoor conditions, is simple, reliable and safe to operate, and can be used for carrying out fracturing tests of different positions and different parameters on a test piece.

Description

Technical Field

[0001] The invention belongs to the technical field of coal safety, and in particular relates to a high-energy light-electricity-force combined fracturing and permeability enhancement test device and a use method thereof. Background Art

[0002] Coal and gas outburst is a complex mine gas dynamic phenomenon in coal mining production, which manifests itself as a large amount of coal suddenly thrown into the tunnel or mining area by the coal body within a certain period of time, and a large amount of gas is released. This phenomenon can cause the coal body to spray a large amount of gas and coal rock into the tunnel or mining area in a short period of time, forming holes of special shapes, accompanied by dynamic effects such as overturning mine cars and destroying supports. The coal powder-gas flow sometimes has the nature of a storm, and the gas runs against the wind flow and can fill tunnels thousands of meters long. In order to solve coal mine gas disasters such as coal and gas outburst, gas extraction has become a key measure. An effective way to improve the effect of gas extraction is to fractur e and increase the permeability of coal seams. Scholars have proposed a variety of technologies, including hydraulic fracturing, carbon dioxide phase change fracturing, microwave permeability enhancement, etc.

[0003] Although there are many coal seam fracturing and permeability enhancement technologies, the permeability of coal seams in my country's coal mines is extremely low and varies significantly between different mining areas, resulting in the lack of universality of traditional single fracturing methods and limited permeability enhancement effects. These methods often cannot adapt to the specific conditions of different mining areas and have unsatisfactory effects in practical applications. Summary of the invention

[0004] In order to solve the above technical problems, the present invention proposes a high-energy light-electricity-force combined fracturing and permeability enhancement test device and a method of using the same to solve the above problems existing in the prior art.

[0005] To achieve the above objectives, in a first aspect, the present invention provides a high-energy light-electricity-force combined fracturing and permeability enhancement test device, comprising:

[0006] The rectangular specimen is a coal rock sample;

[0007] A plurality of loading plates are respectively arranged at the left, top and front directions of the rectangular specimen, and a fracturing groove and a sensor groove are arranged at the end in contact with the rectangular specimen, and a slide rail is installed on the top of the fracturing groove for connecting the fracturing module;

[0008] The fracturing module includes a drill pipe, and a cable chamber and a high-pressure water chamber are provided inside the drill pipe, and the cable chamber is used to lay laser cables and electric pulse cables;

[0009] The laser cables are respectively connected to the laser probe on the outer wall of the drill pipe and the external laser generator;

[0010] The electric pulse cables are respectively connected to the electric pulse probe on the outer wall of the drill pipe and the external discharge capacitor, and the electric pulse probe is respectively provided with a positive electrode and a negative electrode.

[0011] Preferably, the multiple loading platens are all connected to dynamic and static loading cylinders.

[0012] Preferably, an acoustic emission sensor is installed in the sensor slot, and the acoustic emission sensor is connected to an acoustic emission collector.

[0013] Preferably, the fracturing module translates left and right and rotates on the slide rail.

[0014] Preferably, the high-pressure water chamber is connected to a water pressure valve and a high-pressure plunger pump.

[0015] In a second aspect, the present invention also provides a method for using a high-energy light-electricity-force combined fracturing and permeability enhancement test device, comprising the following steps:

[0016] The coal and rock samples are cut and polished into rectangular specimens;

[0017] Applying predetermined dynamic and static triaxial stresses to the rectangular parallelepiped specimen, and using a fracturing module to perform laser irradiation on the surface of the rectangular parallelepiped specimen to form perforations;

[0018] According to the perforation, water is injected through the high-pressure water chamber, and electric pulse discharge is performed using an electric pulse probe to obtain electric pulse fracturing results;

[0019] According to the electric pulse fracturing result, hydraulic fracturing is performed on the perforation to obtain a hydraulic fracturing result;

[0020] According to the hydraulic fracturing results, the parameter combination of laser, electric pulse and water pressure is comprehensively optimized by analyzing crack propagation, temperature field evolution, acoustic emission signal positioning and crushed particle size distribution.

[0021] Preferably, the method of use further comprises: installing a plurality of acoustic emission sensors at different positions of the sensor groove close to the surface of the rectangular specimen, and installing a high-speed camera and an infrared camera on the front and rear sides of the rectangular specimen respectively.

[0022] In a third aspect, the present invention further discloses a computer-readable storage medium having a computer program stored thereon, which implements the steps of the method described in the second aspect when executed by a processor.

[0023] In a fourth aspect, the present invention further discloses a computer program product, comprising a computer program, which implements the steps of the method described in the second aspect when executed by a processor.

[0024] Compared with the prior art, the present invention has the following advantages and technical effects:

[0025] The present invention provides a high-energy light-electricity-force combined fracturing and permeability enhancement test device, comprising: a rectangular specimen, which is a coal rock sample; a loading plate, which is respectively arranged in the left, upper and front directions of the rectangular specimen, and a fracturing groove and a sensor groove are provided at one end in contact with the rectangular specimen, and a slide rail is installed on the top of the fracturing groove for connecting a fracturing module; the fracturing module comprises a drill rod, and a cable chamber and a high-pressure water chamber are provided inside the drill rod, and the cable chamber is used for laying laser cables and electric pulse cables; the laser cable is respectively connected to a laser probe on the outer wall of the drill rod and an external laser generator; the electric pulse cable is respectively connected to the electric pulse probe on the outer wall of the drill rod and an external discharge capacitor, and the electric pulse probe is respectively provided with a positive electrode and a negative electrode.

[0026] The present invention gives full play to the advantages of high laser energy density, good positioning effect, small electric pulse energy attenuation, good local crushing effect, wide application range of hydraulic fracturing, and large fracturing range, and can be carried out under indoor conditions, with simple, reliable and safe operation. At the same time, a fracturing module integrating laser, electric pulse and water pressure is designed, which can be pushed forward and backward and rotated in different directions with the slide rail, so that fracturing tests of different positions and parameters can be carried out on the specimen, and the whole test process can be visualized, the fracturing permeability enhancement effect can be evaluated, and the fracturing parameters can be optimized. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0028] Figure 1 Schematic diagram of a fracturing permeability enhancement test device according to an embodiment of the present invention, (a) is a front view, and (b) is a right view;

[0029] Figure 2 A schematic diagram of a fracturing module and its supporting equipment according to an embodiment of the present invention;

[0030] Among them, 1. rectangular specimen; 2. first loading platen; 3a. second loading platen; 3b. third loading platen; 3c. fourth loading platen; 4. dynamic and static loading cylinder; 5. fracturing groove; 6a. first sensor groove; 6b. second sensor groove; 7. slide rail; 8. fracturing module; 9. acoustic emission sensor; 10. acoustic emission collector; 11. drill pipe; 12. cable chamber; 13. high-pressure water chamber; 14. laser cable; 15. electric pulse cable; 16. laser probe; 17. laser generator; 18. electric pulse probe; 19. discharge capacitor; 20. water pressure valve; 21. high-pressure plunger pump; 22a. positive pole of electric pulse probe; 22b. negative pole of electric pulse probe; 23a. first laser perforation; 23b. second laser perforation; 23c. third laser perforation; 24a. fifth loading platen; 24b. sixth loading platen; 24c. seventh loading platen. DETAILED DESCRIPTION

[0031] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0032] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0033] Embodiment 1

[0034] like Figure 1 As shown, in this embodiment, a high-energy light-electricity-force combined fracturing and permeability enhancement test device is provided, comprising:

[0035] A rectangular parallelepiped specimen 1, wherein the first loading platen 2, the second loading platen 3a, the third loading platen 3b, the fourth loading platen 3c, the fifth loading platen 24a, the sixth loading platen 24b, and the seventh loading platen 24c are respectively provided in the left, upper, and front directions of the rectangular parallelepiped specimen 1, and a total of 7 loading platens are provided;

[0036] Specifically, coal and rock samples were collected on-site at the coal mine and transported back to the laboratory, where they were cut and polished into rectangular specimens 1.

[0037] The seven loading platens can be controlled independently or in groups, and can realize true three-axis zoned dynamic and static combined loading. The loading platens are all made of visual materials, and the test pieces can be photographed and observed by high-speed cameras and infrared cameras.

[0038] There are three loading plates on the top, which are connected to dynamic and static loading cylinders 4; one end of the three upper loading plates in contact with the test piece is provided with a fracturing groove 5 and a first sensor groove 6a and a second sensor groove 6b, and a slide rail 7 is installed on the top of the fracturing groove 5 for connecting a fracturing module 8; two rows of acoustic emission sensors 9 are installed in the first sensor groove 6a and the second sensor groove 6b, and the acoustic emission sensors 9 are connected to an acoustic emission collector 10.

[0039] The fracturing module 8 includes a columnar drill pipe 11, and a cable chamber 12 and a high-pressure water chamber 13 are arranged inside the drill pipe 11; the cable chamber 12 is used to lay a laser cable 14 and an electric pulse cable 15, the laser cable 14 is respectively connected to a laser probe 16 on the outer wall of the drill pipe 11 and an external laser generator 17, and the electric pulse cable 15 is respectively connected to an electric pulse probe 18 on the outer wall of the drill pipe 11 and an external discharge capacitor 19; the high-pressure water chamber 13 is respectively connected to a water pressure valve 20 on the outer wall of the drill pipe and an external high-pressure plunger pump 21; a schematic diagram of the fracturing module and its supporting equipment, as shown in FIG. Figure 2 shown.

[0040] The fracturing module 8 can translate left and right and rotate clockwise and counterclockwise on the slide rail 7; the electric pulse probe 18 has an electric pulse probe positive electrode 22a and an electric pulse probe negative electrode 22b;

[0041] In this embodiment, by providing a fracturing groove 5 and a first sensor groove 6a and a second sensor groove 6b on the loading plate 2, and cooperating with a movable slide rail 7 and a rotatable fracturing module 7, it is possible to realize optical-electrical-mechanical combined fracturing, sensor installation and signal monitoring at different positions of the rectangular specimen 1 while ensuring that the loading plate 2 is not disturbed.

[0042] Embodiment 2

[0043] This embodiment provides a method for using a high-energy light-electricity-force combined fracturing and permeability enhancement test device, including test preparation, laser perforation, electric pulse fracturing, hydraulic fracturing, and test analysis. The specific steps are as follows:

[0044] S1. Experimental preparation;

[0045] 1a) Collect coal and rock samples at the coal mine site and transport them back to the laboratory, test the basic parameters of the coal and rock samples and formulate a test plan, cut and grind them into rectangular parallelepiped specimens 1 and install them;

[0046] 1b) multiple acoustic emission sensors 9 are installed at different positions on the surface of the rectangular specimen 1 in the first sensor slot 6a and the second sensor slot 6b, and a high-speed camera and an infrared camera are installed on the front and rear sides of the specimen respectively;

[0047] 1c) respectively connecting the laser generator 17, the discharge capacitor 19, and the high-pressure plunger pump 21 to the fracturing module 8, and then installing the fracturing module 8 on the right side of the slide rail 7;

[0048] S2, laser perforation;

[0049] 2a) starting the dynamic and static loading cylinder 4 to apply predetermined dynamic and static triaxial stresses to the rectangular specimen 1;

[0050] 2b) Rotate the fracturing module 8 until the laser probe 16 is perpendicular to the surface of the rectangular specimen 1, push the fracturing module 8 from right to left along the slide rail 7, and stop pushing at the predetermined perforation position;

[0051] 2c) turning on the laser generator 17, irradiating the surface of the rectangular specimen 1 at a set frequency and time, and turning off the laser generator 17 after perforations are formed;

[0052] 2d) Repeat step 2c to sequentially complete a plurality of predetermined perforations, and withdraw the fracturing module to the right along the slide rail; the plurality of perforations include: a first laser perforation 23a, a second laser perforation 23b, and a third laser perforation 23c.

[0053] S3, electric pulse fission;

[0054] 3a) Rotate the fracturing module 8 until the hydraulic valve 20 is perpendicular to the surface of the rectangular specimen 1, push the fracturing module 8 from right to left along the slide rail 7, and stop pushing at the first perforation position;

[0055] 3b) Open the hydraulic valve 20, fill the first perforation with water, and then close the hydraulic valve 20; push it to the left in sequence to fill all perforations with water, and then withdraw the fracturing module 8 to the right along the slide rail 7;

[0056] 3c) Rotate the fracturing module 8 until the electric pulse probe 18 is perpendicular to the surface of the rectangular specimen 1, push the fracturing module 8 from right to left along the slide rail 7, stop pushing at the first perforation position, and place the positive and negative electrodes on the electric pulse probe 18 in the drilling water, turn on the discharge capacitor 19, and perform electric pulse discharge according to the predetermined discharge voltage, frequency, and discharge times, and then turn off the discharge capacitor 19;

[0057] 3d) Repeat step 3c to sequentially complete the electric pulse fracturing in multiple perforations, and withdraw the fracturing module to the right along the slide rail;

[0058] S4, hydraulic fracturing;

[0059] 4a) Rotate the fracturing module 8 until the hydraulic valve 20 is perpendicular to the surface of the rectangular specimen 1, push the fracturing module 8 along the slide rail 7 from right to left, and stop pushing at the first perforation position;

[0060] 4b) opening the hydraulic valve 20, hydraulically fracturing the first perforation according to the predetermined fracturing water pressure and loading rate, and closing the hydraulic valve 20 after completion;

[0061] 4c) Repeat step 4b to complete hydraulic fracturing in multiple perforations in sequence, and withdraw the fracturing module to the right along the slide rail;

[0062] S5. Experimental analysis:

[0063] 5a) After the test, the dynamic expansion law of the fracturing crack of the rectangular specimen 1 is analyzed by a high-speed camera, and the evolution law of the surface temperature field of the specimen during the fracturing process is analyzed by an infrared camera;

[0064] 5b) Locate the fracturing position through acoustic emission signals and analyze the evolution of acoustic emission signals at different stages of fracturing;

[0065] 5c) Collecting and sieving the crushed specimens after fracturing to analyze the particle size distribution of the crushed specimens;

[0066] 5d) The fracturing and permeability enhancement effects of the specimens under different test conditions were comprehensively compared, and the optimal parameter combination of laser, electric pulse and water pressure was obtained through analysis.

[0067] Embodiment 3

[0068] This embodiment further discloses a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps of the method described in the second embodiment are implemented.

[0069] Embodiment 4

[0070] This embodiment also discloses a computer program product, including a computer program, which implements the steps of the method described in the second embodiment when executed by a processor.

[0071] The above are only preferred specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A high-energy light-electricity-force combined fracturing and permeability test device, characterized in that: include: The rectangular specimen (1) is a coal rock sample; A plurality of loading plates are respectively arranged in the left, upper and front directions of the rectangular specimen (1); a fracturing groove (5) and a first sensor groove (6a) and a second sensor groove (6b) are provided at one end in contact with the rectangular specimen (1); a slide rail (7) is installed at the top of the fracturing groove (5) for connecting a fracturing module (8); The fracturing module (8) comprises a drill rod (11), a cable chamber (12) and a high-pressure water chamber (13) are arranged inside the drill rod (11), and the cable chamber (12) is used for laying a laser cable (14) and an electric pulse cable (15); The laser cable (14) is respectively connected to a laser probe (16) on the outer wall of the drill rod (11) and an external laser generator (17); The electric pulse cable (15) is respectively connected to an electric pulse probe (18) on the outer wall of the drill pipe and an external discharge capacitor (19), and the electric pulse probe (18) is respectively provided with a positive electrode (22a) and a negative electrode (22b).

2. The device according to claim 1, characterized in that The multiple loading pressure plates are all connected to dynamic and static loading cylinders (4).

3. The device according to claim 1, characterized in that Acoustic emission sensors (9) are installed in the first sensor slot (6a) and the second sensor slot (6b), and the acoustic emission sensors (9) are connected to an acoustic emission collector (10).

4. The device according to claim 1, characterized in that The fracturing module (8) moves horizontally and rotates on the slide rail (7).

5. The device according to claim 1, characterized in that The high-pressure water chamber (13) is connected to a water pressure valve (20) and a high-pressure plunger pump (21).

6. A method for using a high-energy light-electricity-force combined fracturing and permeability enhancement test device according to any one of claims 1 to 5, characterized in that: The following steps are involved: Cutting and grinding the coal and rock samples into rectangular specimens (1); Applying predetermined dynamic and static triaxial stresses to the rectangular parallelepiped specimen (1), and using a fracturing module (8) to perform laser irradiation on the surface of the rectangular parallelepiped specimen (1) to form perforations; According to the perforation, water is injected through the high-pressure water chamber (13), and electric pulse discharge is performed using an electric pulse probe (18) to obtain an electric pulse fracturing result; According to the electric pulse fracturing result, hydraulic fracturing is performed on the perforation to obtain a hydraulic fracturing result; According to the hydraulic fracturing results, the parameter combination of laser, electric pulse and water pressure is comprehensively optimized by analyzing crack propagation, temperature field evolution, acoustic emission signal positioning and crushed particle size distribution.

7. The method of use according to claim 6, characterized in that: It also includes: installing a plurality of acoustic emission sensors (9) at different positions of the first sensor slot (6a) and the second sensor slot (6b) close to the surface of the rectangular parallelepiped specimen (1), and installing a high-speed camera and an infrared camera on the front and rear sides of the rectangular parallelepiped specimen (1), respectively.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to claim 6 are implemented.

9. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to claim 6 are implemented.

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