Laser-assisted water jet rock breaking experimental device and experimental method thereof

Abstract

The application discloses a kind of laser-assisted water jet rock breaking experimental device and experimental method thereof, including test bin, the top side of test bin has installation platform, the other side is provided with window, the bottom wall of window is installed with clamp, the side wall of test bin is provided with drainage notch, displacement mechanism is installed on installation platform, displacement mechanism is installed on support seat, support seat is installed on rock breaking device;Rock breaking device includes laser emitter and high-pressure water jet nozzle, laser emitter is installed on support seat, high-pressure water jet nozzle is installed on support seat by angle adjusting mechanism.The application is aimed at the problems of low rock breaking efficiency, high energy consumption, tool wear and difficulty in breaking high-hardness rock in traditional water jet rock breaking technology, a kind of laser-assisted water jet rock breaking experimental device is proposed, which can provide reliable experimental platform support for revealing the rock breaking mechanism of laser and water jet and optimizing processing parameters.

Description

Technical Field

[0001] This invention relates to the field of high-pressure water jet rock breaking experimental technology, and in particular to a laser-assisted water jet rock breaking experimental device and its experimental method. Background Technology

[0002] Rock breaking is a core component in tunnel boring, mining, oil drilling, and infrastructure construction. High-pressure water jet rock breaking technology, with its advantages of no heat-affected zone, no sparks, good dust suppression, and continuous force, is considered an important supplement and alternative to traditional mechanical cutting tools. However, as engineering projects extend into deeper strata and extremely hard rock areas, traditional pure high-pressure water jet rock breaking technology is facing severe challenges. Existing pure water jet rock breaking methods rely on the impact kinetic energy of high-pressure water and the wedging and tensioning effect of the water. Significant technical limitations exist when dealing with high-hardness, high-density rocks such as granite and basalt. To overcome the extremely high compressive strength and dense structure of hard rock, enormous pumping power is required to generate ultra-high-pressure jets, leading to a sharp increase in energy consumption per unit volume of rock breaking. Prolonged operation under ultra-high pressure conditions exacerbates wear on high-pressure pump valve assemblies, seals, and pipelines, severely impacting the system's reliability and lifespan. In the absence of effective pre-damage or weakening methods, the impact dynamic pressure of water jets alone is insufficient to create sufficiently deep fracture pits and propagating cracks within hard rock, resulting in a slow rock-breaking speed.

[0003] To address these issues, the industry has explored the introduction of thermo-coupling auxiliary methods. Studies have shown that preheating or irradiating rock surfaces with lasers can induce thermally induced microcracks, phase transformations, or thermal stress damage in the surface and subsurface layers of the rock, significantly reducing its local strength and fracture toughness. The synergistic mechanism of laser-assisted high-pressure water jet processing holds promise for significantly reducing the rock-breaking pressure threshold of the water jet and increasing the fragmentation volume. However, current research on the rock-breaking mechanism under the coupling effect of laser and water jet parameters is insufficient, and a controllable experimental setup for laboratory research on the coupling technology between laser-assisted processing and high-pressure water jets is lacking. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a laser-assisted water jet rock-breaking experimental device, which can be used to study the rock-breaking effect of laser-assisted processing coupled with high-pressure water jet by changing the water jet pump pressure, incident angle and laser power.

[0005] Another technical problem to be solved by the present invention is to provide an experimental method that enables laser-assisted water jet rock breaking experiments to be conducted in the laboratory, and to calculate the rock breaking specific energy consumption and energy conversion efficiency during the processing.

[0006] To achieve the above objectives, this application provides a laser-assisted water jet rock-breaking experimental device, including a test chamber. The test chamber has an installation platform on one side of its top and a window on the other side. A clamp for holding a rock sample is installed on the bottom wall of the window. A drainage groove is provided on the side wall of the test chamber. A displacement mechanism is installed on the installation platform. A support base is installed on the displacement mechanism. A rock-breaking device is installed on the support base. The displacement mechanism is used to drive the support base to move in the X-axis and Y-axis directions and to move the rock-breaking device above the window.

[0007] The rock-breaking device includes a laser emitter and a high-pressure water jet nozzle. The laser emitter is mounted on a support base, and the high-pressure water jet nozzle is mounted on the support base via an angle adjustment mechanism.

[0008] The test chamber has a high-speed camera installed on one side of the window for observing and recording the test process.

[0009] The angle adjustment mechanism includes a fixed plate and a rotating plate. One end of the fixed plate is fixedly connected to the support base, and the other end is provided with a transverse hinge hole. Hinges with through holes are respectively installed on both ends of the fixed plate at the hinge hole. The threaded end of the adjusting bolt passes through the through hole of the hinge plate and the hinge hole of the fixed plate and is screwed on with a nut. A rotating plate is fixedly connected to the two hinge plates on the side away from the fixed plate, and a high-pressure water jet nozzle is installed on the rotating plate.

[0010] The rotating plate has a mounting base on the side away from the fixed plate, and the mounting base has a longitudinal mounting hole; the high-pressure water jet nozzle is equipped with an adjusting rod, which passes through the mounting hole of the mounting base; a limit screw is threadedly installed on one side of the mounting base, and the limit screw fixes the adjusting rod when it abuts against the adjusting rod.

[0011] The mounting base is rotatably mounted on the rotating plate so that the high-pressure water jet nozzle can swing along the rotation axis of the mounting base to adjust its angle.

[0012] The support base includes a transverse plate, which is mounted on a displacement mechanism. A longitudinal plate is fixed to one end of the transverse plate, and a transverse extension plate is fixed to the lower end of the transverse plate. A laser emitter is mounted on the longitudinal plate, and an angle adjustment mechanism is mounted on the end of the extension plate away from the longitudinal plate. The extension plate is provided with a clearance hole for the laser to pass through.

[0013] The bottom of the extension plate is equipped with a convex lens bracket via multiple adjusting screws. A convex lens is mounted on the convex lens bracket and is coaxial with the clearance hole. The height of the convex lens is adjusted by adjusting the screws to focus the laser emitted by the laser emitter.

[0014] The displacement mechanism includes a Y-axis adjustment module, an intermediate platform, and an X-axis adjustment module. The Y-axis adjustment module is mounted on the mounting platform along the Y-axis direction. The intermediate platform is mounted on the movable end of the Y-axis adjustment module. The X-axis adjustment module is mounted on the intermediate platform along the X-axis direction. The support base is mounted on the movable end of the X-axis adjustment module. The Y-axis adjustment module and the X-axis adjustment module have the same structure. The Y-axis adjustment module includes a linear guide rail, a ball screw, and a drive motor. The two linear guide rails are arranged in parallel, and a matching slider is slidably installed on the linear guide rails. The ball screw is located between the two linear guide rails. One end of the ball screw is equipped with a bearing seat, and the other end is connected to the output shaft of the drive motor for transmission. A screw nut is installed on the ball screw. The slider and the screw nut form a movable end.

[0015] An experimental method for laser-assisted water jet rock breaking, employing the aforementioned laser-assisted water jet rock breaking experimental device, includes the following steps: S1. Clamp and fix the rock sample to be tested onto the fixture, and pre-adjust the displacement mechanism so that the rock breaking device is located above the edge of the rock sample; S2. Adjust the angle of the rock-breaking device by means of the angle adjustment mechanism to adjust the incident angle of the water jet; S3. Set the processing route, first start the laser emitter, and control the laser emitter to pre-process the rock sample according to the predetermined trajectory; after the pre-processing is completed, adjust the high-pressure water jet nozzle to the initial position of laser emission to start water jet processing, with the processing path coinciding with the laser path; S4. After processing, measure the depth and width of the cut, observe the shape of the cut, compare the effect of traditional high-pressure water jet processing, observe the distribution of internal cracks and micro-damage characteristics of the rock sample using industrial CT, and calculate the rock breaking energy consumption and energy conversion efficiency during the processing.

[0016] The calculation methods for the rock-breaking energy consumption and energy conversion efficiency are as follows: Rock breaking energy consumption The calculation formula is: ; In the formula, The total energy consumption of the test apparatus. To measure the volume of rock broken; Energy consumption of water jet Laser energy consumption sum; Water jet energy consumption ; In the formula, P Indicates the water jet pump pressure. Indicates the flow rate of the water jet. The time for the water jet to break through the rock; Laser energy consumption ; In the formula, For laser power, For laser-assisted time; Measured rock breaking volume ; Taking the logarithm of both sides, transforming it into a linear equation, and fitting it, we get: Solve by substituting different experimental data; In the formula, C represents a constant; a is the pressure index, which reflects the relationship between water jet pressure and rock-breaking effect; b is the laser index, which reflects the contribution of laser power to rock-breaking effect; c is the angle index, which reflects the reduction effect of angle on impact force; and d is the time index. Using relative energy efficiency To compare the effects of a single water jet versus a combined rock-breaking method: ,if A value greater than 1 indicates that laser assistance can effectively improve energy utilization.

[0017] Compared with the prior art, the above-conceptual technical solution conceived in this application has the following beneficial effects: 1. The test chamber of this invention provides a mounting base for the displacement mechanism. One side of the top of the test chamber has a mounting platform for installing the displacement mechanism. The other side of the top of the test chamber has a window, and the bottom wall of the window is fitted with a clamp for holding the rock sample. A support base is mounted on the displacement mechanism, and a rock-breaking device is mounted on the support base. The displacement mechanism can drive the rock-breaking device to move in the X and Y axes, thus enabling it to move and process along a preset path. A laser emitter is used to emit a laser beam to preheat the rock sample fixed on the clamp. In use, a high-pressure water jet nozzle is connected to a high-pressure water system through a high-pressure pipe, and the high-pressure water jet nozzle is used to spray a high-pressure water jet. An angle adjustment mechanism can adjust the incident angle of the water jet. During the experiment, by changing the water jet pump pressure, incident angle, and laser power, the rock-breaking effect of laser-assisted processing coupled with high-pressure water jet technology can be studied.

[0018] 2. In view of the problems of low rock breaking efficiency, high energy consumption, tool wear and difficulty in breaking high hardness rocks in traditional water jet rock breaking technology, this invention proposes a laser-assisted water jet rock breaking experimental device, which can provide a reliable experimental platform to reveal the synergistic rock breaking mechanism of laser and water jet and optimize processing parameters.

[0019] 3. This invention constructs a quantitative analysis system based on energy conservation and multi-parameter coupling to calculate the functional relationship between laser power, water jet pump pressure, incident angle, and rock-breaking effect. This system uses rock-breaking specific energy consumption and energy conversion efficiency as core evaluation indicators. It not only scientifically characterizes the energy efficiency characteristics of rock breaking under laser-thermal coupling, but also reveals the influence weight of each process parameter on the rock-breaking volume through a multivariate nonlinear regression model, thereby determining the optimal parameter matching scheme. This calculation method provides a standardized theoretical basis for the energy efficiency evaluation of laser-assisted water jet rock-breaking technology, significantly improving the controllability and economy of the rock-breaking process, and has theoretical value for widespread application in deep-earth drilling and hard rock tunneling engineering. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in this 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 for this invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0022] Figure 2 This is a schematic diagram of the structure of the displacement mechanism with the support base and rock-breaking device installed on it in this invention.

[0023] Figure 3 This is a schematic diagram of the displacement mechanism in this invention.

[0024] Figure 4 This is a schematic diagram of the displacement mechanism from the bottom view in this invention.

[0025] Figure 5 This is a schematic diagram of the rock-breaking device in this invention.

[0026] Figure 6 for Figure 5 Enlarged structural diagram at point A in the middle.

[0027] Figure label: Test chamber 10, installation platform 11, window 12, drainage outlet 13, Displacement mechanism 20, Y-axis adjustment module 21, linear guide 211, slider 212, bearing housing 213, ball screw 214, drive motor 215, screw nut 216, intermediate platform 22, X-axis adjustment module 23. Support base 30, horizontal plate 31, vertical plate 32, extension plate 33, clearance hole 331.

[0028] Rock breaking device 40, laser emitter 41, adjusting screw 42, convex lens bracket 43, angle adjustment mechanism 44, fixing plate 441, rotating plate 442, hinge plate 443, adjusting bolt 444, nut 445, mounting base 446, limit screw 447, high-pressure water jet nozzle 45, adjusting rod 451; Fixture 50; High-speed camera 60. Detailed Implementation

[0029] To more clearly illustrate the purpose, technical solution, and beneficial effects of this application, a further detailed description of this application is provided below in conjunction with illustrations and specific embodiments. It should be specifically noted that the specific embodiments described below are only for illustrating the technical content of this application and do not constitute a limitation on the scope of protection of this application.

[0030] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "inner," and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present application. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0031] In the description of this invention, unless otherwise explicitly specified and limited, the term "connection" or similar designation indicating a connection between components should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral part; it can be a direct connection or an indirect connection via an intermediate medium; it can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0032] Example 1: See Figure 1-6 This invention provides a laser-assisted water jet rock-breaking experimental device, including a test chamber 10. The test chamber 10 has an installation platform 11 on one side of its top and a window 12 on the other side. A clamp 50 for holding a rock sample is installed on the bottom wall of the window 12. A drainage groove 13 is provided on the side wall of the test chamber 10. A displacement mechanism 20 is installed on the installation platform 11. A support base 30 is installed on the displacement mechanism 20. A rock-breaking device 40 is installed on the support base 30. The displacement mechanism 20 is used to drive the support base 30 to move in the X-axis and Y-axis directions and can move the rock-breaking device 40 above the window 12.

[0033] The rock-breaking device 40 includes a laser emitter 41 and a high-pressure water jet nozzle 45. The laser emitter 41 is mounted on the support base 30, and the high-pressure water jet nozzle 45 is mounted on the support base 30 through an angle adjustment mechanism 44.

[0034] See Figure 1 The test chamber 10 provides a mounting base for the displacement mechanism 20. The test chamber 10 is a box structure welded from steel plates. One side of the top of the test chamber 10 has a mounting platform 11 for mounting the displacement mechanism 20. The other side of the top of the test chamber 10 has a window 12, and the bottom wall of the window 12 is fitted with a clamp 50 for holding the rock sample. A support base 30 is mounted on the displacement mechanism 20, and a rock-breaking device 40 is mounted on the support base 30. The displacement mechanism 20 can drive the rock-breaking device 40 to move in the X and Y axes, thus enabling it to move and process along a preset path. A laser emitter 41 is used to emit a laser beam to preheat the rock sample fixed on the clamp 50. In use, a high-pressure water jet nozzle 45 is connected to a high-pressure water system via a high-pressure pipe. The nozzle diameter of the high-pressure water jet nozzle 45 is 1 mm, used to spray a high-pressure water jet. The laser emitter 41 is a YAG laser emitter, which emits 1064nm near-infrared light that is effectively absorbed by the rock, penetrating to a depth of at least 4 mm to preheat the rock. The angle adjustment mechanism 44 can adjust the incident angle of the water jet. During the experiment, by changing the water jet pump pressure, incident angle, and laser power, it can be used to study the rock-breaking effect of laser-assisted processing coupled with high-pressure water jet technology.

[0035] See Figure 1 The test chamber 10 is equipped with a high-speed camera 60 for observing and recording the test process on one side of the window 12. The lens of the high-speed camera 60 is facing the processing area on the upper side of the rock sample, and it can record the test process during the experiment.

[0036] See Figure 5 , 6 The angle adjustment mechanism 44 includes a fixed plate 441 and a rotating plate 442. One end of the fixed plate 441 is fixedly connected to the support base 30, and the other end is provided with a transverse hinge hole. Hinges 443 with through holes are respectively installed at both ends of the hinge hole on the fixed plate 441. The threaded end of the adjusting bolt 444 passes through the through hole of the hinge plate 443 and the hinge hole of the fixed plate 441 and is screwed with a nut 445. The rotating plate 442 is fixedly connected to the two hinge plates 443 on the side away from the fixed plate 441, and the high-pressure water jet nozzle 45 is installed on the rotating plate 442. With the above structure, the front and rear spray angle of the high-pressure water jet nozzle 45 can be adjusted. When the angle needs to be adjusted, the nut 445 is loosened, and after adjusting to the preset angle, the nut 445 is tightened.

[0037] Further, see Figure 6 A mounting base 446 is installed on the side of the rotating plate 442 away from the fixed plate 441. The mounting base 446 has a longitudinal mounting hole. An adjusting rod 451 is installed on the high-pressure water jet nozzle 45, and the adjusting rod 451 passes through the mounting hole of the mounting base 446. A limit screw 447 is threadedly installed on one side of the mounting base 446. When the limit screw 447 abuts against the adjusting rod 451, it fixes the adjusting rod 451. With the above structure, the distance between the high-pressure water jet nozzle 45 and the rock sample can be adjusted. When the distance needs to be adjusted, loosen the limit screw 447, move the adjusting rod 451 up and down, adjust it to the preset position, and then tighten the limit screw 447.

[0038] See Figure 6 The mounting base 446 is rotatably mounted on the rotating plate 442, allowing the high-pressure water jet nozzle 45 to swing left and right along the rotation axis of the mounting base 446 to adjust its angle. Specifically, a through hole can be provided on the rotating plate 442, and the threaded end of the connecting screw passes through the through hole of the rotating plate 442 before being screwed onto the mounting base 446. When the angle needs to be adjusted, the connecting screw is turned, and after the high-pressure water jet nozzle 45 swings left and right to the preset position, the connecting screw is tightened.

[0039] See Figure 3 The support base 30 includes a transverse plate 31, which is mounted on the displacement mechanism 20. A longitudinal plate 32 is fixedly connected to one end of the transverse plate 31, and a transverse extension plate 33 is fixedly connected to the lower end of the transverse plate 31. The laser emitter 41 is mounted on the longitudinal plate 32, and an angle adjustment mechanism 44 is mounted on the end of the extension plate 33 away from the longitudinal plate 32. The extension plate 33 is provided with a clearance hole 331 for the laser to pass through. Through the above structure, the laser emitter 41 and the high-pressure water jet nozzle 45 can be installed.

[0040] See Figure 5 The bottom of the extension plate 33 is equipped with a convex lens bracket 43 via three or four adjusting screws 42. A convex lens is mounted on the convex lens bracket 43, and the convex lens is coaxial with the clearance hole 331. The height position of the convex lens is adjusted by adjusting the adjusting screws 42 to focus the laser emitted by the laser emitter 41.

[0041] Specifically, the convex lens bracket 43 is provided with through holes of the same number and corresponding positions as the adjusting screws 42. The convex lens bracket 43 is inserted through the through holes onto the adjusting screws 42. Each adjusting screw 42 has a nut screwed onto its lower side or both sides of the convex lens bracket 43. By rotating the nut, the height position of the convex lens bracket 43 is adjusted. The convex lens on the convex lens bracket 43 is aligned with the clearance hole 331.

[0042] See Figure 3 , 4The displacement mechanism 20 includes a Y-axis adjustment module 21, an intermediate platform 22, and an X-axis adjustment module 23. The Y-axis adjustment module 21 is mounted on the mounting platform 11 along the Y-axis direction. The intermediate platform 22 is mounted on the movable end of the Y-axis adjustment module 21. The X-axis adjustment module 23 is mounted on the intermediate platform 22 along the X-axis direction. A support base 30 is mounted on the movable end of the X-axis adjustment module 23. Figure 1 The Y-axis adjustment module 21 is used to drive the rock-breaking device 40 to move along the Y-axis direction, and the X-axis adjustment module 23 is used to drive the rock-breaking device 40 to move along the X-axis direction.

[0043] Specifically, the Y-axis adjustment module 21 and the X-axis adjustment module 23 have the same structure. The Y-axis adjustment module 21 includes a linear guide rail 211, a ball screw 214, and a drive motor 215. The two linear guide rails 211 are arranged in parallel, and a matching slider 212 is slidably installed on the linear guide rails 211. The ball screw 214 is located between the two linear guide rails 211. One end of the ball screw 214 is equipped with a bearing seat 213, and the other end is connected to the output shaft of the drive motor 215 for transmission. A screw nut 216 is installed on the ball screw 214. The slider 212 and the screw nut 216 form a movable end.

[0044] The linear guide rail 211, bearing seat 213, and drive motor 215 of the Y-axis adjustment module 21 are mounted on the mounting platform 11; the intermediate platform 22 is mounted on the movable end formed by the slider 212 and the lead screw nut 216 on the Y-axis adjustment module 21.

[0045] The linear guide rail 211, bearing seat 213 and drive motor 215 of the X-axis adjustment module 23 are mounted on the intermediate platform 22; the support seat 30 is mounted on the movable end formed by the slider 212 and the lead screw nut 216 on the X-axis adjustment module 23.

[0046] Example 2: An experimental method for laser-assisted water jet rock breaking, using a laser-assisted water jet rock breaking experimental device as described in Example 1, includes the following steps: S1. The rock sample to be tested is clamped and fixed onto the clamp 50, and the displacement mechanism 20 is pre-adjusted so that the rock breaking device 40 is located above the edge of the rock sample. S2. Adjust the angle of the rock-breaking device 40 by adjusting the angle adjustment mechanism 44 to adjust the incident angle of the water jet; S3. Set the processing route, first start the laser emitter 41, and control the laser emitter 41 to pre-process the rock sample according to the predetermined trajectory; after the pre-processing is completed, adjust the high-pressure water jet nozzle 45 to the initial position of laser emission to start water jet processing, and the processing path coincides with the laser path; S4. After processing, measure the depth and width of the cut, observe the shape of the cut, compare the effect of traditional high-pressure water jet processing, observe the distribution of internal cracks and micro-damage characteristics of the rock sample using industrial CT, and calculate the rock breaking energy consumption and energy conversion efficiency during the processing.

[0047] Furthermore, The calculation methods for rock breaking energy consumption and energy conversion efficiency are as follows: Rock breaking energy consumption The calculation formula is: ; In the formula, The total energy consumption of the test apparatus. This represents the measured volume of broken rock.

[0048] Energy consumption of water jet Laser energy consumption sum.

[0049] Among them, water jet energy consumption ; In the formula, P Indicates the water jet pump pressure. Indicates the flow rate of the water jet. This refers to the time it takes for the water jet to break through the rock.

[0050] Water jet flow rate , The diameter of the high-pressure water jet nozzle is 45.

[0051] Water jet velocity Calculations can be made using pump pressure: ; In the formula, This is the flow coefficient, typically taken as 0.94-0.98. For pump pressure, This is the density of water.

[0052] Laser energy consumption ; In the formula, For laser power, For laser-assisted time.

[0053] Measured rock breaking volume ; Taking the logarithm of both sides, transforming it into a linear equation, and fitting it, we get: Different experimental data can be input into Matlab software to solve for the coefficients; In the formula, C represents a constant; a is the pressure index, which reflects the relationship between water jet pressure and rock-breaking effect; b is the laser index, which reflects the contribution of laser power to rock-breaking effect; c is the angle index, which reflects the reduction effect of angle on impact force; and d is the time index.

[0054] The energy conversion efficiency of this device can be achieved through limited rock-breaking energy. Total energy consumption Calculation of the ratio: .

[0055] because Due to the difficulty in calculating precisely, relative energy efficiency is used here. To compare the effects of a single water jet versus a combined rock-breaking method: ,if A value greater than 1 indicates that laser assistance can effectively improve energy utilization.

[0056] This invention constructs a quantitative analysis system based on energy conservation and multi-parameter coupling to calculate the functional relationship between laser power, water jet pump pressure, incident angle, and rock-breaking effect. This system uses rock-breaking specific energy consumption and energy conversion efficiency as core evaluation indicators. It not only scientifically characterizes the energy efficiency of rock breaking under laser-thermal coupling, but also reveals the influence weight of each process parameter on the rock-breaking volume through a multivariate nonlinear regression model, thereby determining the optimal parameter matching scheme. This calculation method provides a standardized theoretical basis for the energy efficiency evaluation of laser-assisted water jet rock-breaking technology, significantly improving the controllability and economy of the rock-breaking process, and possesses theoretical value for widespread application in deep-earth drilling and hard rock tunneling engineering.

[0057] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention, and no reference numerals in the claims should be construed as limiting the scope of the claims.

[0058] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A laser-assisted water jet rock-breaking experimental device, characterized in that: The test chamber (10) has an installation platform (11) on one side of its top and a window (12) on the other side. The bottom wall of the window (12) is equipped with a clamp (50) for holding rock samples. The side wall of the test chamber (10) is provided with a drainage slot (13). The installation platform (11) is equipped with a displacement mechanism (20). The displacement mechanism (20) is equipped with a support seat (30). The support seat (30) is equipped with a rock breaking device (40). The displacement mechanism (20) is used to drive the support seat (30) to move in the X-axis and Y-axis directions and can move the rock breaking device (40) above the window (12). The rock-breaking device (40) includes a laser emitter (41) and a high-pressure water jet nozzle (45). The laser emitter (41) is mounted on a support base (30), and the high-pressure water jet nozzle (45) is mounted on the support base (30) through an angle adjustment mechanism (44).

2. The laser-assisted water jet rock-breaking experimental device according to claim 1, characterized in that, The test chamber (10) is equipped with a high-speed camera (60) for observing and recording the test process on one side of the window (12).

3. The laser-assisted water jet rock-breaking experimental device according to claim 1, characterized in that, The angle adjustment mechanism (44) includes a fixed plate (441) and a rotating plate (442). One end of the fixed plate (441) is fixedly connected to the support base (30), and the other end is provided with a transverse hinge hole. The fixed plate (441) is equipped with hinge plates (443) with through holes at both ends of the hinge hole. The threaded end of the adjusting bolt (444) passes through the through hole of the hinge plate (443) and the hinge hole of the fixed plate (441) and is screwed with a nut (445). The two hinge plates (443) are fixedly connected to the rotating plate (442) on the side away from the fixed plate (441). The high-pressure water jet nozzle (45) is installed on the rotating plate (442).

4. The laser-assisted water jet rock-breaking experimental device according to claim 3, characterized in that, The rotating plate (442) has a mounting base (446) on the side away from the fixed plate (441), and the mounting base (446) has a longitudinal mounting hole; the high-pressure water jet nozzle (45) has an adjusting rod (451) installed on it, and the adjusting rod (451) passes through the mounting hole of the mounting base (446); a limit screw (447) is threadedly installed on one side of the mounting base (446), and the limit screw (447) fixes the adjusting rod (451) when it abuts against the adjusting rod (451).

5. The laser-assisted water jet rock-breaking experimental device according to claim 4, characterized in that, The mounting base (446) is rotatably mounted on the rotating plate (442) so that the high-pressure water jet nozzle (45) can swing along the rotation axis of the mounting base (446) to adjust the angle.

6. A laser-assisted water jet rock-breaking experimental device according to any one of claims 1 to 5, characterized in that, The support base (30) includes a transverse plate (31), which is mounted on the displacement mechanism (20). A longitudinal plate (32) is fixed to one end of the transverse plate (31), and a transverse extension plate (33) is fixed to the lower end of the transverse plate (31). A laser emitter (41) is mounted on the longitudinal plate (32), and an angle adjustment mechanism (44) is mounted on the end of the extension plate (33) away from the longitudinal plate (32). The extension plate (33) is provided with a clearance hole (331) for the laser to pass through.

7. The laser-assisted water jet rock-breaking experimental device according to claim 6, characterized in that, The bottom of the extension plate (33) is equipped with a convex lens bracket (43) by multiple adjusting screws (42), and a convex lens is installed on the convex lens bracket (43). The convex lens is coaxial with the clearance hole (331). The height position of the convex lens is adjusted by adjusting screws (42) to focus the laser emitted by the laser emitter (41).

8. The laser-assisted water jet rock-breaking experimental device according to claim 1, characterized in that, The displacement mechanism (20) includes a Y-axis adjustment module (21), an intermediate platform (22), and an X-axis adjustment module (23). The Y-axis adjustment module (21) is mounted on the mounting platform (11) along the Y-axis direction. The intermediate platform (22) is mounted on the movable end of the Y-axis adjustment module (21). The X-axis adjustment module (23) is mounted on the intermediate platform (22) along the X-axis direction. The support base (30) is mounted on the movable end of the X-axis adjustment module (23). The Y-axis adjustment module (21) and the X-axis adjustment module (23) have the same structure. The Y-axis adjustment module (21) includes a linear guide rail (211), a ball screw (214) and a drive motor (215). The two linear guide rails (211) are arranged in parallel, and a matching slider (212) is slidably installed on the linear guide rails (211). The ball screw (214) is located between the two linear guide rails (211). One end of the ball screw (214) is equipped with a bearing seat (213), and the other end is connected to the output shaft of the drive motor (215) for transmission. A screw nut (216) is installed on the ball screw (214). The slider (212) and the screw nut (216) form a movable end.

9. An experimental method for laser-assisted water jet rock breaking, characterized in that, The experimental device for laser-assisted water jet rock breaking according to any one of claims 1-8 is used, and the experimental method includes the following steps: S1. The rock sample to be tested is clamped and fixed on the clamp (50), and the displacement mechanism (20) is pre-adjusted so that the rock breaking device (40) is located above the edge of the rock sample; S2. Adjust the angle of the rock-breaking device (40) by means of the angle adjustment mechanism (44) to adjust the incident angle of the water jet; S3. Set the processing route, first start the laser emitter (41), control the laser emitter (41) to pre-process the rock sample according to the predetermined trajectory; after the pre-processing is completed, adjust the high-pressure water jet nozzle (45) to the initial position of laser emission to start water jet processing, and the processing path coincides with the laser path; S4. After processing, measure the depth and width of the cut, observe the shape of the cut, compare the effect of traditional high-pressure water jet processing, observe the distribution of internal cracks and micro-damage characteristics of the rock sample using industrial CT, and calculate the rock breaking energy consumption and energy conversion efficiency during the processing.

10. The experimental method according to claim 9, characterized in that, The calculation methods for the rock-breaking energy consumption and energy conversion efficiency are as follows: Rock breaking energy consumption The calculation formula is: ; In the formula, The total energy consumption of the test apparatus. To measure the volume of rock broken; Energy consumption of water jet Laser energy consumption sum; Water jet energy consumption ; In the formula, P Indicates the water jet pump pressure. Indicates the flow rate of the water jet. The time for the water jet to break through the rock; Laser energy consumption ; In the formula, For laser power, For laser-assisted time; Measured rock breaking volume ; Taking the logarithm of both sides, transforming it into a linear equation, and fitting it, we get: Solve by substituting different experimental data; In the formula, C represents a constant; a is the pressure index, which reflects the relationship between water jet pressure and rock-breaking effect; b is the laser index, which reflects the contribution of laser power to rock-breaking effect; c is the angle index, which reflects the reduction effect of angle on impact force; and d is the time index. Using relative energy efficiency To compare the effects of a single water jet versus a combined rock-breaking method: ,if A value greater than 1 indicates that laser assistance can effectively improve energy utilization.

Images