A recyclable pressure relief type hydrogeological test device and method

Abstract

The application provides a recyclable pressure relief type hydrogeological test device and method, and relates to the technical field of hydrogeology. The device comprises a sealing mechanism, a negative pressure main body, a negative pressure execution mechanism, a valve mechanism and a detection mechanism. The sealing mechanism is used for separating and forming a to-be-measured section in a borehole. The negative pressure main body is located between the sealing mechanisms, is internally provided with a working cavity and is in communication with the to-be-measured section through the valve mechanism. The negative pressure execution mechanism is used for adjusting the volume of the working cavity to form negative pressure or drainage reset. The detection mechanism is used for collecting water pressure data in the to-be-measured section. Through hydraulic control, continuous operation of downhole vacuumizing, instantaneous pressure relief, reset and recycling is realized, the device does not need to be taken out of the ground, the test efficiency and data accuracy of deep holes and multilayer aquifers are significantly improved, and the device has compact structure and simple operation.

Description

Technical Field

[0001] This invention relates to the field of hydrogeology, and more specifically, to a recyclable pressure-relief hydrogeological testing device and method. Background Technology

[0002] In existing technologies, rock formation permeability coefficients are mainly determined through casing-based oscillation tests or mobile downhole plug tests, which to some extent meet the needs of rock formation permeability measurement. However, these technologies have many limitations in practical applications, especially in deep or ultra-deep hole operating environments. Frequent tripping of drilling tools is not only time-consuming and inefficient, but also significantly increases equipment wear and construction costs. At the same time, the compressed air scheme in casing-based oscillation tests can affect the accuracy of the water level recovery curve due to unnatural disturbances introduced by external pressurization, leading to data analysis bias. Furthermore, the sealing reliability problem at the casing interface is particularly prominent under high pressure or complex formation conditions, which can easily cause crossflow or leakage, affecting the validity of the test. In addition, mobile downhole plug test devices are limited by their non-recyclable energy storage and drainage mechanisms, making it difficult to support continuous multi-stage rapid testing, which seriously restricts the overall exploration progress. Summary of the Invention

[0003] In view of this, the purpose of the present invention is to provide a recyclable pressure relief hydrogeological testing device and method to improve testing efficiency and the accuracy and reliability of test data.

[0004] In a first aspect, this application provides a recyclable pressure-relief hydrogeological testing device, comprising:

[0005] The sealing mechanism includes a first sealing member and a second sealing member, which are used to separate and form a section to be measured within the borehole;

[0006] The negative pressure body is located between the first and second sealing components. The negative pressure body has a first inner cavity and a first inlet and outlet. The first inlet and outlet connect the first inner cavity and the space outside the negative pressure body where the section to be measured is located.

[0007] A negative pressure actuator is connected to a negative pressure body. The negative pressure actuator is used to divide and form a working chamber in the first inner cavity and to adjust the volume of the working chamber.

[0008] The valve mechanism is connected to the negative pressure body and is used to open or close the connection passage between the working chamber and the first inlet / outlet.

[0009] The testing agency is used to collect water pressure values ​​within the section to be measured.

[0010] In an optional implementation, the negative pressure actuator includes:

[0011] A piston assembly includes a first piston body slidably disposed in a first inner cavity, and a working chamber is formed on one side of the first piston body.

[0012] A drive assembly is used to drive the first piston body to slide along the first inner cavity to adjust the volume of the working cavity.

[0013] In an optional implementation, the piston assembly further includes:

[0014] The first piston rod is slidably inserted through the first partition plate inside the negative pressure body, and one end of the first piston rod is fixedly connected to the first piston body.

[0015] The second piston body is located on the side of the first partition away from the first piston body and is fixedly connected to the end of the first piston rod away from the first piston body. One side of the second piston body, together with the first piston rod and the first partition, forms a first sealing cavity, and the other side of the second piston body, together with the inner wall of the negative pressure body, forms a second sealing cavity.

[0016] The drive assembly is used to pressurize the first sealing cavity or the second sealing cavity.

[0017] In an optional implementation, the driving component includes:

[0018] The first driving component is located outside the borehole and is connected to the first sealing cavity through the first pipeline. The first driving component is used to supply pressurized fluid to the first sealing cavity.

[0019] The second drive unit is located outside the borehole and is connected to the second sealing cavity through the second pipeline. The second drive unit is used to supply pressurized fluid to the second sealing cavity.

[0020] In an optional embodiment, the second driving member is also used to drive the valve mechanism to open or close the connection passage between the working chamber and the first inlet / outlet.

[0021] In an optional implementation, the valve mechanism includes:

[0022] The third piston body is slidably disposed in the first inner cavity;

[0023] The second piston rod is provided inside the negative pressure body with a second partition plate. The second piston rod is slidably inserted through the second partition plate. One end of the second piston rod is fixedly connected to the third piston body. The second piston rod, the second partition plate, the third piston body and the inner wall of the negative pressure body form a third sealing cavity. The third sealing cavity is connected to the second driving component through a second pipeline.

[0024] The valve plate is located on the side of the second partition away from the third piston body and between the inlet / outlet and the working chamber. The valve plate is fixedly connected to the inner wall of the negative pressure body. The valve plate has a valve port that connects the working chamber and the first inlet / outlet.

[0025] The valve body, located on the side of the valve plate near the second partition, and fixedly connected to the end of the second piston rod opposite to the third piston body, is used to open and close the valve port; and

[0026] The elastic element connects to the valve body and provides a spring force to the valve body that tends to move closer to the valve plate.

[0027] In an optional embodiment, the first driving member is also used to drive the first and second sealing members to open or close the section to be measured.

[0028] In an optional implementation, the testing organization includes:

[0029] The piezometer has a negative pressure body with a second inner cavity and a second inlet / outlet. The second inner cavity is separated from the first inner cavity. The second inlet / outlet connects the second inner cavity to the space outside the negative pressure body where the section to be measured is located. The piezometer is located outside the negative pressure body and is used to collect the water pressure value within the section to be measured.

[0030] The ground terminal, located outside the borehole and connected to the piezometer signal, is used to display and store water pressure values ​​or liquid level information.

[0031] Secondly, this application provides a recyclable pressure relief hydrogeological testing method, which utilizes the aforementioned recyclable pressure relief hydrogeological testing device, including:

[0032] S1: Open the connection passage between the working chamber and the first inlet / outlet through the valve mechanism;

[0033] S2: Reduce the volume of the working chamber through a negative pressure actuator;

[0034] S3: The valve mechanism closes the connection between the working chamber and the first inlet / outlet, and the negative pressure actuator pressurizes the first and second packers, so that the inner wall of the borehole, the first and second packers form the section to be measured, and the volume of the working chamber is increased; at the same time, the detection mechanism collects the initial water pressure value in the section to be measured.

[0035] S4: Open the connection passage between the working chamber and the first inlet / outlet through the valve mechanism to allow water in the section to be measured to enter the working chamber; at the same time, collect the actual water pressure value in the section to be measured and the actual time corresponding to the actual water pressure value through the detection mechanism.

[0036] S5: Until the actual water pressure value in the section to be measured is equal to the initial water pressure value;

[0037] S6: Repeat steps S2 to S5 until all target locations have been measured.

[0038] In an optional embodiment, the cyclic depressurization hydrogeological testing method provided in this application further includes:

[0039] Based on the actual water pressure value, the initial water pressure value, water density, and gravitational acceleration, determine the drawdown corresponding to the actual water pressure value;

[0040] The measured curve was determined based on the drawdown and actual time.

[0041] Based on the calibrated theoretical and measured curves between theoretical drawdown and theoretical time, the derivative coefficient and storage coefficient of the section to be measured are determined.

[0042] The permeability coefficient of the section to be measured is determined based on the derivative coefficient and the thickness of the aquifer in the section to be measured.

[0043] This application provides a recyclable pressure-relief hydrogeological testing device and method. The device includes a sealing mechanism, a negative pressure body, a negative pressure actuator, a valve mechanism, and a detection mechanism. The sealing mechanism is used to divide the borehole into sections to be measured. The negative pressure body is located between the sealing mechanisms and has a working chamber inside, which is connected to the section to be measured through the valve mechanism. The negative pressure actuator is used to adjust the volume of the working chamber to create negative pressure or drain and reset. The detection mechanism is used to collect water pressure data in the section to be measured. Continuous operation of downhole vacuuming, instantaneous pressure relief, reset, and recirculation is achieved through hydraulic control, without the need to remove the equipment from the surface. This significantly improves the testing efficiency and data accuracy of deep boreholes and multi-layer aquifers. The device has a compact structure and is easy to operate.

[0044] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0045] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0046] Figure 1 This diagram illustrates the structure of a recyclable pressure-relief hydrogeological testing device provided in an embodiment of the present invention.

[0047] Figure 2 A schematic flowchart of a recyclable depressurization hydrogeological testing method provided by an embodiment of the present invention is shown;

[0048] Figure 3 A schematic diagram of the structure of an electronic device provided in an embodiment of the present invention is shown.

[0049] Key component symbols: 110-First packer; 120-Second packer; 130-Measurement section; 200-Negative pressure body; 210-First inner cavity; 211-First inlet / outlet; 212-Second partition; 213-Third sealing cavity; 220-Working cavity; 221-First partition; 222-First sealing cavity; 223-Second sealing cavity; 310-Third piston body; 320-Second piston rod; 330-Elastic element; 340-Valve body; 350-Valve plate; 360-Valve port; 410-First piston body; 420-First piston rod; 430-Second piston body; 510-Second inner cavity; 520-Second inlet / outlet; 530-Pyrometer; 610-First driving element; 620-Second driving element; 630-Ground terminal; 710-First pipeline; 720-Second pipeline; 800-Drill hole. Detailed Implementation

[0050] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0051] This application provides a recyclable pressure-relief hydrogeological testing device, see reference. Figure 1 As shown in the embodiment of this application, the recyclable pressure relief hydrogeological testing device includes: a sealing mechanism, a negative pressure body 200, a negative pressure actuator, a valve mechanism, and a testing mechanism.

[0052] The sealing mechanism includes a first sealing member 110 and a second sealing member 120, which are used to separate and form a section 130 to be measured within the borehole 800. A negative pressure body 200 is located between the first sealing member 110 and the second sealing member 120. The negative pressure body 200 has a first inner cavity 210 and a first inlet / outlet 211, which connects the first inner cavity 210 and the space outside the negative pressure body 200 where the section 130 to be measured is located. A negative pressure actuator is connected to the negative pressure body 200 and is used to separate and form a working chamber 220 within the first inner cavity 210 and to adjust the volume of the working chamber 220. A valve mechanism is connected to the negative pressure body 200 and is used to open or close the connection passage between the working chamber 220 and the first inlet / outlet 211. A detection mechanism is used to collect the water pressure value within the section 130 to be measured.

[0053] In this embodiment, the first sealing member 110 and the second sealing member 120 of the sealing mechanism are arranged axially spaced along the borehole 800 and are radially expandable to tightly fit the inner wall of the borehole 800, thereby separating and forming the measurement segment 130 located between the two within the borehole 800; the negative pressure body 200 is located between the first sealing member 110 and the second sealing member 120, and is fixedly connected to the first sealing member 110 and the second sealing member 120 by a sealing connector or integrally formed, ensuring hydraulic isolation between the measurement segment 130 and other borehole segments; the negative pressure body 200 has a first inner cavity 2 inside. 10. The first inner cavity 210 is connected to the space outside the negative pressure body 200 of the section to be measured 130 through the first inlet / outlet 211 opened on the side wall of the negative pressure body 200; the negative pressure actuator is connected to the negative pressure body 200 and divides the first inner cavity 210 into two sub-cavities, one of which serves as the working cavity 220 and the other as a balancing cavity for adjusting the volume of the working cavity 220; the valve mechanism is installed on the negative pressure body 200 and is located in the communication path between the working cavity 220 and the first inlet / outlet 211; the detection mechanism collects and transmits the water pressure value in the section to be measured 130.

[0054] When the test apparatus is in operation, it is first lowered to the target depth within borehole 800. The first and second sealing members 110 and 120 are expanded by the sealing mechanism to form the measurement section 130 with the inner wall of borehole 800. Next, the negative pressure actuator increases the volume of the working chamber 220, creating negative pressure. At this time, the valve mechanism is closed, isolating the working chamber 220 from the measurement section 130. After the negative pressure is established, the valve mechanism is instantly opened, allowing high-pressure groundwater in the measurement section 130 to rapidly flow into the working chamber 220 under pressure differential, achieving instantaneous pressure relief within the measurement section 130. After pressure relief, the valve mechanism closes, and the detection mechanism monitors the pressure recovery process within the measurement section 130, recording pressure changes over time. After one test, the groundwater drawn into the working chamber 220 can be discharged through the negative pressure actuator, restoring it and creating negative pressure again. This allows for the next test to be conducted directly within the same borehole 800 without removing the apparatus.

[0055] This embodiment integrates negative pressure formation, pressure relief triggering, pressure monitoring, and reset drainage functions into one unit, and directly completes the negative pressure reconstruction of the working chamber 220 downhole. This enables continuous multiple tests of the test section 130 during a single downhole run, significantly improving operational efficiency in deep or ultra-deep borehole environments. Because the negative pressure actuator buffers the impact of its movement on the fluid within the borehole 800 during the volume change of the working chamber 220 through a balance chamber, disturbance to the water body in the test section 130 during the test preparation stage is avoided, thus ensuring the initial authenticity of the pressure recovery data and improving test accuracy. The rapid opening and closing characteristics of the valve mechanism achieve near-instantaneous pressure relief boundary conditions, which better match the instantaneous point sink model in groundwater seepage theory, making subsequent parameter calculations more accurate. The overall structure has high integration, a simplified number of control pipelines, reduces system complexity and sealing difficulty, and improves the reliability of the device in harsh downhole environments.

[0056] In an optional embodiment, the negative pressure actuator includes a piston assembly and a drive assembly, wherein the piston assembly includes a first piston body 410, the first piston body 410 is slidably disposed in a first inner cavity 210, and a working cavity 220 is formed on one side of the first piston body 410; the drive assembly is used to drive the first piston body 410 to slide along the first inner cavity 210 to adjust the volume of the working cavity 220.

[0057] Furthermore, the piston assembly also includes: a first piston rod 420 and a second piston body 430, wherein a first partition 221 is provided inside the negative pressure body 200, the first piston rod 420 is slidably inserted through the first partition 221, and one end of the first piston rod 420 is fixedly connected to the first piston body 410; the second piston body 430 is located on the side of the first partition 221 away from the first piston body 410, and is fixedly connected to the end of the first piston rod 420 away from the first piston body 410, one side of the second piston body 430, the first piston rod 420, and the first partition 221 form a first sealing cavity 222, and the other side of the second piston body forms a second sealing cavity 223 with the inner wall of the negative pressure body 200; wherein, the driving assembly is used to pressurize the first sealing cavity 222 or the second sealing cavity 223;

[0058] The drive assembly includes: a first drive member 610 and a second drive member 620, wherein the first drive member 610 is located outside the borehole 800 and is connected to the first sealing cavity 222 through the first pipe 710, and the first drive member 610 is used to supply pressurized fluid to the first sealing cavity 222; the second drive member 620 is located outside the borehole 800 and is connected to the second sealing cavity 223 through the second pipe 720, and the second drive member 620 is used to supply pressurized fluid to the second sealing cavity 223; and the first drive member 610 is also used to drive the first sealing member 110 and the second sealing member 120 to open or close the section to be measured 130; the second drive member 620 is also used to drive the valve mechanism to open or close the connection passage between the working cavity 220 and the first inlet and outlet 211.

[0059] In this embodiment, the negative pressure actuator includes a piston assembly and a drive assembly. The piston assembly includes a first piston body 410, a first piston rod 420, and a second piston body 430. A first partition 221 is provided inside the negative pressure body 200. The first partition 221 is fixed to the inner wall of the negative pressure body 200 and divides its interior into two adjacent cavities. The first piston rod 420 is slidably axially through a through hole in the center of the first partition 221. A sealing structure is provided at the through hole to ensure sealing during sliding. One end of the first piston rod 420 is fixedly connected to the first piston body 410. The first piston body 410 is located on one side of the first partition 221 and slides in the first inner cavity 210 on that side. The first piston body 410 divides the first inner cavity 210 into two sub-cavities, one facing the first piston rod 420. A sub-cavity on one side of an inlet / outlet 211 constitutes a working chamber 220, and another sub-cavity is a balancing chamber used to adjust the volume of the working chamber 220; the second piston body 430 is located on the other side of the first partition 221 away from the first piston body 410, and is fixedly connected to the other end of the first piston rod 420 away from the first piston body 410; the outer edge of the second piston body 430 is also provided with a sealing element, so that it can slide in the cavity on this side of the first partition 221; the second piston body 430, the first piston rod 420 and the first partition 221 together form a closed first sealing cavity 222, the first sealing cavity 222 is located on the side of the second piston body 430 facing the first partition 221, and the other side of the second piston body 430 and the inner wall of the negative pressure body 200 in this area form a second sealing cavity 223;

[0060] The drive assembly is used to pressurize the first sealing cavity 222 or the second sealing cavity 223 to drive the piston assembly to move. The drive assembly includes a first drive member 610 and a second drive member 620. Both the first drive member 610 and the second drive member 620 are located at the ground control end outside the borehole 800. The first drive member 610 is connected to the first sealing cavity 222 through the first pipeline 710 and is used to supply pressurized fluid to the first sealing cavity 222. When the pressure in the first sealing cavity 222 increases, it pushes the second piston body 430 to move away from the first partition 221, thereby causing the first piston body 410 to move away from the first inlet and outlet 211 in the middle of the first inner cavity 210, thereby increasing the volume of the working cavity 220 to form a negative pressure. Furthermore, the first drive unit 610 is also connected to the first sealing member 110 and the second sealing member 120 through a branch of the first pipeline 710 or another independent pipeline, for supplying pressurized fluid to the sealing member to drive its expansion or contraction, thereby opening or closing the section to be measured 130; the second drive unit 620 is connected to the second sealing cavity 223 through the second pipeline 720, for supplying pressurized fluid to the second sealing cavity 223. When the pressure in the second sealing cavity 223 increases, it pushes the second piston body 430 and the entire piston assembly to move towards the first partition 221, thereby driving the first piston body 410 to reduce the volume of the working cavity 220 to discharge the liquid therein; at the same time, the second drive unit 620 is also connected to the valve mechanism through a branch of the second pipeline 720 or another independent pipeline, for supplying pressurized fluid to the drive part of the valve mechanism, thereby controlling the valve mechanism to open or close the connection passage between the working cavity 220 and the first inlet and outlet 211.

[0061] Through the coordinated control of the first drive unit 610 and the second drive unit 620, not only can the volume of the working chamber 220 be precisely adjusted to complete the establishment of negative pressure and reset drainage, but also the sealing and release of the packer and the opening and closing of the valve mechanism can be controlled simultaneously, thereby integrating the management of the entire test process. The first drive unit 610 is responsible for both negative pressure formation and packer sealing, which simplifies the control relationship between the packer mechanism and the negative pressure actuator, reduces the number of independent pipelines, and reduces the complexity of the device and the risk of downhole sealing. The second drive unit 620 is responsible for both reset drainage and valve control, which ensures the coordination and consistency of the timing of pressure relief triggering and piston reset, avoids vacuum loss or pressure disturbance caused by asynchronous control, and improves the convenience and reliability of operation.

[0062] In an optional embodiment, the valve mechanism includes: a third piston body 310, a second piston rod 320, a valve plate 350, a valve body 340, and an elastic element 330. The third piston body 310 is slidably disposed within the first inner cavity 210. A second partition 212 is disposed within the negative pressure body 200. The second piston rod 320 slidably passes through the second partition 212, and one end of the second piston rod 320 is fixedly connected to the third piston body 310. The second piston rod 320, the second partition 212, the third piston body 310, and the inner wall of the negative pressure body 200 form a third sealing cavity 213. The third sealing cavity 213 is connected to the second drive via a second pipe 720. The valve plate 350 is located on the side of the second partition 212 away from the third piston body 310 and between the inlet / outlet and the working chamber 220. The valve plate 350 is fixedly connected to the inner wall of the negative pressure body 200. The valve plate 350 has a valve port 360, which connects the working chamber 220 and the first inlet / outlet 211. The valve body 340 is located on the side of the valve plate 350 near the second partition 212 and is fixedly connected to the end of the second piston rod 320 away from the third piston body 310. The valve body is used to open and close the valve port 360. The elastic element 330 is connected to the valve body 340 and is used to provide the valve body 340 with an elastic force that tends to move closer to the valve plate 350.

[0063] In this embodiment, the valve mechanism includes a third piston body 310, a second piston rod 320, a valve plate 350, a valve body 340, and an elastic element 330. The third piston body 310 is slidably disposed in the first inner cavity 210 of the negative pressure body 200, specifically located in a designated area adjacent to the working cavity 220 within the first inner cavity 210. A second partition 212 is also disposed within the negative pressure body 200, and the second partition 212 is fixed in the first inner cavity 210 and further divides the cavity area where the third piston body 310 is located. The second piston rod 320 is slidably inserted axially. A through hole is provided in the center of the second partition 212, and a sealing structure is provided at the through hole to ensure the sealing during the sliding process; one end of the second piston rod 320 is fixedly connected to the third piston body 310. The second piston rod 320, the second partition 212, the third piston body 310 and the inner wall of the negative pressure body 200 in this area together form a closed third sealing cavity 213. The third sealing cavity 213 is connected to the second driving member 620 located outside the borehole 800 through the second pipe 720, so that the second driving member 620 can supply or release pressure fluid to the third sealing cavity 213.

[0064] The valve plate 350 is located on the side of the second partition 212 away from the third piston body 310, and is fixedly installed on the inner wall of the negative pressure body 200, and its installation position is on the communication path between the first inlet / outlet 211 and the working chamber 220; the valve plate 350 has a valve port 360, which directly connects the working chamber 220 and the first inlet / outlet 211; the valve body 340 is located on the side of the valve plate 350 close to the second partition 212, and is fixedly connected to the end of the second piston rod 320 away from the third piston body 310. The shape and size of the valve body 340 are configured to form a sealing fit with the valve port 360 on the valve plate 350. When the valve body 340 abuts against the valve port 360, it can block the communication between the working chamber 220 and the first inlet / outlet 211; when the valve body 340 moves away from the valve port 360, it opens the communication passage.

[0065] The elastic element 330 is connected between the valve body 340 and the inner wall of the second partition 212 or the negative pressure body 200. It is pre-compressed or pre-stretched, thereby providing the valve body 340 with an elastic force that always tends to move towards the valve plate 350, that is, causing the valve body 340 to move towards the closed valve port 360.

[0066] The valve mechanism works as follows: When it is necessary to open the connection between the working chamber 220 and the first inlet / outlet 211, the second driving member 620 supplies pressurized fluid to the third sealing chamber 213, increasing the pressure inside the third sealing chamber 213. The pressure pushes the third piston body 310, causing the second piston rod 320 to move away from the second partition 212, which in turn causes the valve body 340 to overcome the elastic force of the elastic member 330 and move away from the valve plate 350, thereby opening the valve port 360. When it is necessary to close the passage, the second driving member 620 releases the pressurized fluid in the third sealing chamber 213, reducing the pressure in the third sealing chamber 213. At this time, the elastic force of the elastic member 330 pushes the valve body 340 back to its original position, causing it to press against the valve port 360 again, thus achieving a sealed closure. Due to the presence of the elastic element 330, the valve mechanism is in the closed state by default when there is no external force driving it. This improves the safety and reliability of the system and prevents accidental opening. At the same time, through the transmission between the third piston body 310 and the second piston rod 320, the hydraulic drive of the second driving element 620 is smoothly converted into the linear motion of the valve body 340, realizing the rapid and controllable opening and closing of the valve. This meets the requirements of instantaneous pressure relief for valve action speed and reduces the complexity of the device and potential failure points.

[0067] In an optional embodiment, the detection mechanism includes a piezometer 530 and a ground terminal 630. The negative pressure body 200 has a second inner cavity 510 and a second inlet / outlet 520. The second inner cavity 510 is separated from the first inner cavity 210. The second inlet / outlet 520 connects the second inner cavity 510 and the space outside the negative pressure body 200 where the section to be measured 130 is located. The piezometer 530 is located outside the negative pressure body 200 and is used to collect the water pressure value in the section to be measured 130. The ground terminal 630 is located outside the borehole 800 and is signal-connected to the piezometer 530. The ground terminal 630 is used to display and store the water pressure value or liquid level information.

[0068] In this embodiment, the detection mechanism includes a piezometer 530 and a ground terminal 630. The negative pressure body 200 has an independent second inner cavity 510, which is structurally separated from the first inner cavity 210 to ensure that its internal environment does not interfere with the working chamber 220. A second inlet / outlet 520 is provided on the side wall of the negative pressure body 200, connecting the second inner cavity 510 to the measured section 130 outside the negative pressure body 200, allowing groundwater in the measured section 130 to freely enter the second inner cavity 510 and contact the sensing end of the piezometer 530. The piezometer 530 is located within the negative pressure body 200. On the outside, the sensing part of the piezometer 530 extends into the second inner cavity 510 through the second inlet and outlet 520 or is directly exposed to the water in the section to be measured 130 to collect the water pressure value in the section to be measured 130; the main body of the piezometer 530 can be installed on the outer wall of the negative pressure body 200 or integrated into its interior through a waterproof sealing structure to protect it from the harsh downhole environment; the ground terminal 630 is set in the ground control area outside the borehole 800 and is connected to the piezometer 530 through a waterproof and tensile-resistant signal transmission line. The ground terminal 630 receives the water pressure data collected by the piezometer 530 and displays, stores and analyzes it in real time.

[0069] By setting up a separate second inner cavity 510 as the pressure sensing cavity of the piezometer 530, the sensing part of the piezometer 530 is protected from direct hydraulic impact or air bubble interference caused by the operation of the working cavity 220, while ensuring that it can accurately reflect the hydrostatic pressure changes of the section 130 to be measured. The signal connection between the piezometer 530 and the ground terminal 630 allows the operator to monitor the pressure recovery curve during the test in real time on the ground, facilitating timely judgment of the test status and data validity. The storage function of the ground terminal 630 completely records the pressure change data over time, providing an accurate data foundation for subsequent parameter calculations based on instantaneous point sink theory.

[0070] The test apparatus provided in this application embodiment also includes a processing mechanism, which is used to determine the drawdown corresponding to the actual water pressure value based on the actual water pressure value, the initial water pressure value, the water density, and the gravitational acceleration; to determine the measured curve based on the drawdown and the actual time; to determine the derivative coefficient and the storage coefficient of the section to be measured 130 based on the calibrated theoretical curve and the measured curve between the theoretical drawdown and the theoretical time; and to determine the permeability coefficient of the section to be measured 130 based on the derivative coefficient and the aquifer thickness of the section to be measured 130.

[0071] In this embodiment, the drawdown corresponding to the actual water pressure value is determined based on the actual water pressure value, the initial water pressure value, the water density, and the gravitational acceleration, using the following formula:

[0072]

[0073] In the formula, The water level drawdown over time is expressed in meters (m). This is the initial water pressure value, in Pa. The water pressure value varies over time. For the density of water, It is the acceleration due to gravity;

[0074] Based on the measured curve and the theoretical curve, determine the overlap position of the measured curve and the theoretical curve, and record the coordinates of the matching point at the overlap position. For example, the coordinates of the matching point at the overlap position on the measured curve are... The coordinates of the matching point at the coincidence position on the theoretical curve are: ;

[0075] Based on the coordinates of the matching points at the overlapping locations, the derivative coefficients and water storage coefficients of the section to be measured can be determined using the following formula:

[0076]

[0077]

[0078] In the formula, These are the derivative coefficients, in units of . , The instantaneous volume of water pumped out, in units of That is, the volume of the working chamber. This represents the initial maximum drawdown, in meters (m). For theoretical depth reduction, the unit is meters. This refers to the actual drawdown depth, in meters (m). The water storage coefficient is dimensionless. This is the actual time, expressed in seconds. The borehole radius is in meters. The theoretical time is expressed in seconds (s).

[0079] Based on the derivative coefficient and the aquifer thickness of the section to be measured, the permeability coefficient of the section to be measured can be determined using the following formula:

[0080]

[0081] In the formula, Permeability coefficient, unit: , These are the derivative coefficients, in units of . , The thickness of the aquifer is expressed in meters (m) and can be determined using geological data.

[0082] In this application, the theoretical curve can be obtained in the following way:

[0083] First, based on the basic data, determine the radial flow diffusion equation:

[0084]

[0085] In the formula, The second derivative of the depth of descent with respect to radial distance is used to describe the curvature of the depth of descent curve. Since the water flow is radially symmetrical, the characteristics of the cylindrical coordinate system need to be considered. For terms that change over time, The water storage coefficient is dimensionless. The radial distance from the center of the well, in meters. These are the derivative coefficients, in units of . , Permeability coefficient, unit: ;

[0086] Then, before the experiment begins (t=0), the entire experimental setup is in hydrostatic pressure equilibrium, and the drawdown of the entire aquifer system is 0. At t=0, a volume of water V is instantaneously removed from the well. The volume of water V instantaneously extracted from the aquifer can be mathematically described using the instantaneous point sink:

[0087]

[0088] In the formula, Dirac function : ;in, This indicates that the effect is instantaneous, occurring only at t=0. The unit is... ;

[0089] Dirac function : ,in, This indicates that the point of effect is the only point that has an impact, and the unit is r=0 (the location of the borehole). ;

[0090] Finally, solving the diffusion equation with the instantaneous point sink term yields the analytical solution for the wellbore drawdown (r→0) over time. After dimensionless processing of the analytical solution, the theoretical standard curve of the instantaneous point sink solution is obtained, i.e., the theoretical curve: In the formula, For dimensionless depth reduction, Time is dimensionless; where, , .

[0091] The test device provided in this application embodiment, through the cooperation of the downhole integrated negative pressure actuator and valve mechanism, can complete the entire operation cycle of "forming negative pressure - instantaneous pressure relief - data acquisition - reset and drainage" in a single downhole operation. This eliminates the need to lift the device to the surface for drainage and reset after each test, thereby reducing the time spent on frequent drilling and unloading in deep or ultra-deep borehole environments. It makes it possible to conduct rapid and continuous permeability tests on multiple aquifers at different depths within the same borehole, significantly improving the overall efficiency of field exploration operations. Furthermore, the balanced design of the first baffle, first sealing chamber, and second sealing chamber during the adjustment of the working chamber volume to form negative pressure by the negative pressure actuator avoids direct disturbance of the water in the borehole by the piston movement, ensuring the original water level at the initial moment of the test. The valve mechanism, utilizing a combination of elastic elements and hydraulic drive, enables rapid opening and reliable sealing of the connection pathway. This simulates near-ideal "instantaneous pressure relief" boundary conditions, making the water level recovery curve obtained from the experiment more consistent with the "instantaneous point sink" mathematical model in groundwater seepage theory. This provides a more accurate data foundation for subsequent calculations of rock permeability coefficients based on this model, improving the reliability of parameter solutions. By integrating functions such as negative pressure formation, valve control, and packer drive into a hydraulic system controlled by a few surface drive components, the number of independent control pipelines in the downhole device is significantly reduced. This not only lowers the system's structural complexity and manufacturing cost but also reduces potential leakage points passing through the packer mechanism, improving the reliability of downhole sealing in high-pressure, complex formations. Simultaneously, the centralized surface control simplifies on-site operation procedures, reduces the technical requirements for operators and the risk of human error, making the equipment easier to deploy and maintain.

[0092] This application provides a cyclic pressure relief hydrogeological testing method, which utilizes the aforementioned cyclic pressure relief hydrogeological testing device. (See attached document.) Figure 2 As shown in the embodiments of this application, the cyclic depressurization hydrogeological testing method includes:

[0093] S1: Open the connection passage between the working chamber and the first inlet / outlet through the valve mechanism;

[0094] S2: Reduce the volume of the working chamber through a negative pressure actuator;

[0095] S3: The valve mechanism closes the connection between the working chamber and the first inlet / outlet, and the negative pressure actuator pressurizes the first and second packers, so that the inner wall of the borehole, the first and second packers form the section to be measured, and the volume of the working chamber is increased; at the same time, the detection mechanism collects the initial water pressure value in the section to be measured.

[0096] S4: Open the connection passage between the working chamber and the first inlet / outlet through the valve mechanism to allow water in the section to be measured to enter the working chamber; at the same time, collect the actual water pressure value in the section to be measured and the actual time corresponding to the actual water pressure value through the detection mechanism.

[0097] S5: Until the actual water pressure value in the section to be measured is equal to the initial water pressure value;

[0098] S6: Repeat steps S2 to S5 until all target locations have been measured.

[0099] In this embodiment of the application, the process of conducting the test using a recyclable pressure-relief hydrogeological testing device is as follows:

[0100] First, the connection passage between the working chamber and the first inlet / outlet is opened by operating the valve mechanism, so that the working chamber is initially connected to the borehole environment;

[0101] Next, the piston assembly is driven to move by the negative pressure actuator, reducing the volume of the working chamber, thereby discharging any residual liquid or gas that may be present in the working chamber.

[0102] Subsequently, the connection between the working chamber and the first inlet / outlet is closed via a valve mechanism to ensure isolation of the working chamber from the outside. Simultaneously, a negative pressure actuator supplies pressurized fluid to the first and second packers, causing them to expand radially and fit tightly against the borehole wall, thus creating a closed measurement section within the borehole. While the sealing is complete, the negative pressure actuator increases the volume of the working chamber, creating a negative pressure environment. During this stage, the detection mechanism begins to collect and record the initial water pressure value within the measurement section.

[0103] Subsequently, the connection between the working chamber and the first inlet / outlet is quickly opened via the valve mechanism. Because the working chamber is under negative pressure, the groundwater in the section to be measured rushes into the working chamber instantly under the pressure difference, achieving rapid depressurization of the water pressure in the section to be measured. During this process, the detection mechanism continuously collects the actual water pressure values ​​in the section to be measured and simultaneously records the actual time corresponding to each actual water pressure value, thereby obtaining the pressure-time curve during the water level recovery process.

[0104] Continuous monitoring continues until the actual water pressure in the measured section returns to the initial water pressure value, indicating that the depressurization-recovery test is complete. If testing is required at other locations within the same borehole, the above steps—from draining the liquid from the working chamber, re-establishing negative pressure, to completing water level recovery monitoring—are repeated until all target locations are measured.

[0105] In practice, by cyclically performing negative pressure establishment, instantaneous depressurization, pressure monitoring, and reset drainage downhole, continuous and rapid hydrogeological tests were conducted on multiple borehole sections during a single downhole operation. Specifically, the removal of residual media from the working chamber and the formation of a stable negative pressure before the formal test ensured the instantaneity and consistency of the depressurization action, improving the repeatability of the test. The simultaneous sealing and negative pressure establishment shortened the test preparation time and improved operational efficiency. Furthermore, the continuous monitoring of the pressure recovery process by the testing agency provided a complete and accurate data foundation for calculating the rock permeability coefficient based on the instantaneous point sink theory.

[0106] In an optional embodiment, the cyclic depressurization hydrogeological testing method provided in this application further includes:

[0107] Based on the actual water pressure value, the initial water pressure value, water density, and gravitational acceleration, determine the drawdown corresponding to the actual water pressure value;

[0108] The measured curve was determined based on the drawdown and actual time.

[0109] Based on the calibrated theoretical and measured curves between theoretical drawdown and theoretical time, the derivative coefficient and storage coefficient of the section to be measured are determined.

[0110] The permeability coefficient of the section to be measured is determined based on the derivative coefficient and the thickness of the aquifer in the section to be measured.

[0111] In this embodiment, the drawdown corresponding to the actual water pressure value is determined based on the actual water pressure value, the initial water pressure value, the water density, and the gravitational acceleration, using the following formula:

[0112]

[0113] In the formula, The water level drawdown over time is expressed in meters (m). This is the initial water pressure value, in Pa. The water pressure value varies over time. For the density of water, It is the acceleration due to gravity;

[0114] Based on the measured curve and the theoretical curve, determine the overlap position of the measured curve and the theoretical curve, and record the coordinates of the matching point at the overlap position. For example, the coordinates of the matching point at the overlap position on the measured curve are... The coordinates of the matching point at the coincidence position on the theoretical curve are: ;

[0115] Based on the coordinates of the matching points at the overlapping locations, the derivative coefficients and water storage coefficients of the section to be measured can be determined using the following formula:

[0116]

[0117]

[0118] In the formula, These are the derivative coefficients, in units of . , The instantaneous volume of water pumped out, in units of That is, the volume of the working chamber. This represents the initial maximum drawdown, in meters (m). For theoretical depth reduction, the unit is meters. This refers to the actual drawdown depth, in meters (m). The water storage coefficient is dimensionless. This is the actual time, expressed in seconds. The borehole radius is in meters. The theoretical time is expressed in seconds (s).

[0119] Based on the derivative coefficient and the thickness of the aquifer in the section to be measured, the permeability coefficient of the section to be measured can be determined using the following formula:

[0120]

[0121] In the formula, Permeability coefficient, unit: , These are the derivative coefficients, in units of . , The thickness of the aquifer is expressed in meters (m) and can be determined using geological data.

[0122] It should be noted that the principle of the recirculating pressure relief hydrogeological test method provided in this application embodiment to solve the technical problem is similar to that of the recirculating pressure relief hydrogeological test device provided in this application embodiment. Therefore, the implementation of the recirculating pressure relief hydrogeological test method provided in this application embodiment can refer to the implementation of the recirculating pressure relief hydrogeological test device provided in this application embodiment, and the repeated parts will not be described again.

[0123] After introducing the recyclable pressure relief hydrogeological testing method and apparatus provided in the embodiments of this application, the electronic equipment provided in the embodiments of this application will be briefly introduced next.

[0124] See Figure 3 As shown, the electronic device 500 provided in this application embodiment includes at least a processor 501, a memory 502, and a computer program stored in the memory 502 and capable of running on the processor 501. When the processor 501 executes the computer program, it implements the cyclic decompression hydrogeological test method provided in this application embodiment.

[0125] The electronic device 500 provided in this application embodiment may further include a bus 503 connecting different components (including processor 501 and memory 502). The bus 503 represents one or more types of bus structures, including memory bus, peripheral bus, local area bus, etc.

[0126] Memory 502 may include readable storage media in the form of volatile memory, such as random access memory (RAM) 5021 and / or cache memory 5022, and may further include read-only memory (ROM) 5023. Memory 502 may also include a program tool 5025 having a set (at least one) of program modules 5024, including but not limited to an operating subsystem, one or more application programs, other program modules, and program data, each or some combination of these examples may include an implementation of a network environment.

[0127] Processor 501 can be a single processing element or a collective term for multiple processing elements. For example, processor 501 can be a central processing unit (CPU) or one or more integrated circuits configured to implement the cyclic decompression hydrogeological testing method provided in the embodiments of this application. Specifically, processor 501 can be a general-purpose processor, including but not limited to CPUs, application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc.

[0128] Electronic device 500 can communicate with one or more external devices 504 (e.g., keyboard, remote control, etc.), and also with one or more devices that enable a user to interact with electronic device 500 (e.g., mobile phone, computer, etc.), and / or with devices that enable electronic device 500 to communicate with one or more other electronic devices 500 (e.g., router, modem, etc.). This communication can be performed through input / output (I / O) interface 505. Furthermore, electronic device 500 can also communicate with one or more networks (e.g., local area network (LAN), wide area network (WAN), and / or public networks, such as the Internet) through network adapter 506. Figure 3 As shown, network adapter 506 communicates with other modules of electronic device 500 via bus 503. It should be understood that, although... Figure 3 As not shown, other hardware and / or software modules may be used in conjunction with the electronic device 500, including but not limited to microcode, device drivers, redundant processors, external disk drive arrays, Redundant Arrays of Independent Disks (RAID) subsystems, tape drives, and data backup storage subsystems.

[0129] It should be noted that, Figure 3 The electronic device 500 shown is merely an example and should not impose any limitations on the functionality and scope of use of the embodiments of this application.

[0130] The following describes the computer-readable storage medium provided in the embodiments of this application. The computer-readable storage medium provided in the embodiments of this application stores computer instructions, which, when executed by a processor, implement the cyclic depressurization hydrogeological testing method provided in the embodiments of this application. Specifically, the computer instructions can be built into or installed in the processor, so that the processor can implement the cyclic depressurization hydrogeological testing method provided in the embodiments of this application by executing the built-in or installed computer instructions.

[0131] In addition, the cyclic depressurization hydrogeological test method provided in this application embodiment can also be implemented as a computer program product. The computer program product includes program code, which implements the cyclic depressurization hydrogeological test method provided in this application embodiment when running on a processor.

[0132] The computer program product provided in this application embodiment may employ one or more computer-readable storage media, which may be, but is not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination thereof. Specifically, more specific examples (a non-exhaustive list) of computer-readable storage media include electrical connections with one or more wires, portable disks, hard disks, RAM, ROM, erasable programmable read-only memory (EPROM), optical fibers, portable compact disc read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0133] The computer program product provided in this application embodiment can be a CD-ROM and include program code, and can also run on electronic devices such as computers. However, the computer program product provided in this application embodiment is not limited thereto. In this application embodiment, the computer-readable storage medium can be any tangible medium that contains or stores program code, which can be used by or in conjunction with an instruction execution system, device, or apparatus.

[0134] It should be noted that although several units or sub-units of the device have been mentioned in the detailed description above, this division is merely exemplary and not mandatory. In fact, according to embodiments of this application, the features and functions of two or more units described above can be embodied in one unit. Conversely, the features and functions of one unit described above can be further divided and embodied by multiple units.

[0135] Furthermore, although the operations of the method of this application are described in a specific order in the accompanying drawings, this does not require or imply that these operations must be performed in that specific order, or that all the operations shown must be performed to achieve the desired result. Additionally or alternatively, certain steps may be omitted, multiple steps may be combined into one step, and / or one step may be broken down into multiple steps.

[0136] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0137] Obviously, those skilled in the art can make various modifications and variations to the embodiments of this application without departing from the spirit and scope of the embodiments of this application. Therefore, if these modifications and variations to the embodiments of this application fall within the scope of the claims of this application and their equivalents, this application also intends to include these modifications and variations.

Claims

1. A recyclable pressure-relief hydrogeological testing device, characterized in that, include: The sealing mechanism includes a first sealing member and a second sealing member, which are used to separate and form a section to be measured within the borehole; A negative pressure body is located between the first sealing member and the second sealing member. The negative pressure body has a first inner cavity and a first inlet and outlet. The first inlet and outlet connect the first inner cavity and the space outside the negative pressure body where the section to be measured is located. A negative pressure actuator, connected to the negative pressure body, is used to divide and form a working chamber in the first inner cavity and to adjust the volume of the working chamber. The negative pressure actuator includes: a piston assembly, which includes a first piston body slidably disposed in the first inner cavity, with one side of the first piston body forming the working chamber; a drive assembly, used to drive the first piston body to slide along the first inner cavity to adjust the volume of the working chamber; the piston assembly further includes: a first piston rod, in which a first partition is disposed within the negative pressure body, the first piston rod slidably passing through the first partition, and one end of the first piston rod being fixedly connected to the first piston body; and a second piston body located behind the first partition. A first piston body is fixedly connected to one side of the first piston body and the end of the first piston rod opposite to the first piston body. One side of the second piston body, together with the first piston rod and the first partition, forms a first sealing cavity. The other side of the second piston body, together with the inner wall of the negative pressure body, forms a second sealing cavity. The driving assembly is used to pressurize either the first or second sealing cavity. The driving assembly includes: a first driving member located outside the borehole and connected to the first sealing cavity via a first pipe, the first driving member being used to supply pressurized fluid to the first sealing cavity; and a second driving member located outside the borehole and connected to the second sealing cavity via a second pipe, the second driving member being used to supply pressurized fluid to the second sealing cavity. A valve mechanism, connected to the negative pressure body, is used to open or close the connection passage between the working chamber and the first inlet / outlet. The valve mechanism includes: a third piston body slidably disposed in the first inner cavity; a second piston rod, through which a second partition is disposed within the negative pressure body, one end of which is fixedly connected to the third piston body; the second piston rod, the second partition, the third piston body, and the inner wall of the negative pressure body form a third sealing cavity, which is connected to the working chamber via a second pipeline. The system includes: a second driving component; a valve plate located on the side of the second partition away from the third piston body and between the inlet / outlet and the working chamber; the valve plate being fixedly connected to the inner wall of the negative pressure body; the valve plate having a valve port communicating with the working chamber and the first inlet / outlet; a valve body located on the side of the valve plate near the second partition and fixedly connected to the end of the second piston rod away from the third piston body; the valve body being used to open and close the valve port; and an elastic element connected to the valve body, the elastic element being used to provide a spring force to the valve body that tends to move closer to the valve plate. The testing agency is used to collect the water pressure value within the section to be measured.

2. The recirculating pressure-relief hydrogeological testing device according to claim 1, characterized in that, The second driving component is also used to drive the valve mechanism to open or close the connection passage between the working chamber and the first inlet / outlet.

3. The recirculating pressure-relief hydrogeological testing device according to claim 1, characterized in that, The first driving member is also used to drive the first sealing member and the second sealing member to open or close the segment to be measured.

4. The recirculating pressure-relief hydrogeological testing device according to claim 1, characterized in that, The testing institutions include: A piezometer, wherein the negative pressure body has a second inner cavity and a second inlet / outlet, the second inner cavity being separated from the first inner cavity, the second inlet / outlet connecting the second inner cavity and the space outside the negative pressure body where the section to be measured is located, the piezometer being located outside the negative pressure body, and the piezometer being used to collect the water pressure value within the section to be measured; and A ground terminal, located outside the borehole and connected to the piezometer, is used to display and store water pressure values ​​or liquid level information.

5. A recyclable pressure-relief hydrogeological testing method, using the recyclable pressure-relief hydrogeological testing device as described in any one of claims 1 to 4, characterized in that, include: S1: The valve mechanism opens the connection passage between the working chamber and the first inlet / outlet; S2: The volume of the working chamber is reduced by the negative pressure actuator; S3: The valve mechanism closes the connection between the working chamber and the first inlet / outlet, and the negative pressure actuator pressurizes the first and second packers, so that the inner wall of the borehole, the first and second packers form the section to be measured, and the volume of the working chamber is increased; at the same time, the detection mechanism collects the initial water pressure value in the section to be measured. S4: The valve mechanism opens the connection passage between the working chamber and the first inlet / outlet, so that water in the section to be measured can enter the working chamber; at the same time, the detection mechanism collects the actual water pressure value in the section to be measured and the actual time corresponding to the actual water pressure value. S5: Until the actual water pressure value in the section to be measured returns to the initial water pressure value; S6: Repeat steps S2 to S5 until all target locations have been measured.

6. The cyclic depressurization hydrogeological testing method according to claim 5, characterized in that, Also includes: Based on the actual water pressure value, the initial water pressure value, water density, and gravitational acceleration, determine the drawdown corresponding to the actual water pressure value; Based on the drawdown and the actual time, the measured curve is determined; Based on the calibrated theoretical curve between theoretical drawdown and theoretical time and the measured curve, the derivative coefficient and storage coefficient of the section to be measured are determined. The permeability coefficient of the section to be measured is determined based on the derivative coefficient and the thickness of the aquifer in the section to be measured.

Images