Pumping device and permeability coefficient calculation method

Abstract

This invention provides a pumping device and a method for calculating the permeability coefficient. The pumping device includes a packing system, a pumping control system, a sealing system, and an observation system. The packing system includes an upper packer, a lower packer, and a packer pressurization device. The pumping control system includes terminal equipment and a variable frequency pump. The outlet of the variable frequency pump is connected to the ground via an outlet pipe. The sealing system includes a lower conversion chamber, an upper conversion chamber, a connecting pipe, and a sealing device. The observation system is used to collect first pressure data of the test layer, second pressure data of the upper part of the test layer, and flow rate data of the outlet pipe. The test layer is located between the upper and lower packers. The terminal equipment is connected to the observation system and the variable frequency pump, respectively, and is used to control the variable frequency pump to pump water based on the first pressure data and to calculate the permeability coefficient based on the relevant data. This invention is applicable to multi-layer aquifer testing and improves the accuracy of permeability coefficient calculation.

Description

Technical Field

[0001] This invention relates to the field of pumping test calculation technology, and in particular to a pumping device and a method for calculating the permeability coefficient. Background Technology

[0002] In existing technologies, conventional pumping tests mostly employ the full-bore pumping method, which involves directly installing pumping equipment in the borehole to pump water, and calculating the aquifer's permeability coefficient by observing water level changes and pumping rates. Common theoretical calculation formulas include the Theis formula and the Jacob formula, etc. These formulas are based on the assumption of homogeneous aquifers and do not fully consider the effects of cross-layer seepage between multiple aquifers.

[0003] In traditional pumping tests, the pumping equipment is placed in the target aquifer. During pumping, due to hydraulic connection, the water level of the upper aquifer also drops, resulting in the observation data including cross-flow effects. However, existing calculation formulas do not effectively separate this effect, leading to significant deviations in the calculated permeability coefficient. This causes the following problems: 1) Existing formulas do not fully consider cross-flow, resulting in inaccurate permeability coefficient calculations, affecting engineering design and safety assessments; 2) The drop in the water level of the upper aquifer during pumping may cause large-scale ground subsidence, degradation of surface vegetation, and other environmental problems; 3) Full-hole pumping cannot achieve large drawdown pumping for a specific aquifer, making it difficult to simulate actual engineering conditions (such as deep dewatering after foundation pit excavation). Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a pumping device and a method for calculating the permeability coefficient, so as to alleviate the above-mentioned problems existing in the related art.

[0005] In a first aspect, embodiments of the present invention provide a pumping device, comprising: a packing system, a pumping control system, a sealing system, and an observation system; the packing system includes an upper packer, a lower packer, and a packer pressurization device; the upper packer, the lower packer, and the sealing system are all vertically arranged within a pumping hole; the upper packer and the lower packer are both located underground and are spaced apart vertically; the upper packer is connected to the packer pressurization device and the lower packer respectively via packer control pipelines; the pumping control system includes terminal equipment and a variable frequency pump; the variable frequency pump is fixedly installed on the upper part of the lower packer; the outlet end of the variable frequency pump is connected to the ground via an outlet pipeline; the sealing system includes a lower conversion chamber, an upper conversion chamber, a connecting pipe, and a sealing device; both the lower conversion chamber and the upper conversion chamber adopt... The structure is hollow; the upper part of the lower conversion chamber is fixedly connected to the lower part of the upper packer, and the lower part of the upper conversion chamber is fixedly connected to the upper part of the upper packer through the sealing device; the first part of the outlet pipe passes through the lower conversion chamber, the upper packer, the sealing device, and the upper packer; the lower part of the lower conversion chamber is sleeved on the outer periphery of the second part of the outlet pipe, and the upper part of the upper conversion chamber is sleeved on the outer periphery of the third part of the outlet pipe; the observation system is used to collect the first pressure data of the test layer, the second pressure data of the upper part of the test layer, and the flow data of the outlet pipe; the test layer is located between the upper packer and the lower packer; the terminal equipment is connected to the observation system and the variable frequency water pump respectively, and is used to control the variable frequency water pump to pump water based on the first pressure data.

[0006] As one possible implementation, the outlet pipeline includes a first pipe section, a second pipe section, a third pipe section, a fourth pipe section, and a fifth pipe section arranged sequentially from bottom to top; the pumping control system also includes a one-way valve; the lower end of the first pipe section is connected to the outlet end of the variable frequency water pump through the one-way valve, the upper end of the first pipe section is fixedly connected to the lower end of the second pipe section, the upper end of the second pipe section is fixedly connected to the lower end of the connecting pipe, the upper end of the third pipe section is fixedly connected to the lower end of the fourth pipe section, the upper end of the fourth pipe section is fixedly connected to the lower end of the fifth pipe section, and the fifth pipe section extends from its lower end to the ground; the lower part of the lower conversion chamber is fitted around the outer periphery of the second pipe section; the third pipe section passes through the upper packer and the sealing device; the third pipe section uses the connecting pipe; the upper part of the upper conversion chamber is fitted around the outer periphery of the fourth pipe section.

[0007] As one possible implementation, the second pipe section uses a lower threaded rod, the connecting pipe uses an aluminum-plastic pipe, and the fourth pipe section uses an upper threaded rod; the sealing device further includes a lower inner connector, the lower threaded rod, a lower core connector, a lower adapter, an upper adapter, the upper threaded rod, the upper core connector, and an upper inner connector; the upper end of the first pipe section is fixedly connected to the lower end of the lower threaded rod through the lower inner connector, and the upper end of the lower threaded rod is fixedly connected to the lower end of the aluminum-plastic pipe through the lower adapter; the upper end of the aluminum-plastic pipe is fixedly connected to the lower end of the upper threaded rod through the upper adapter, and the upper end of the upper threaded rod is fixedly connected to the lower end of the fifth pipe section through the upper inner connector; the lower core connector is fixedly installed in the lower part of the lower conversion chamber, and the lower core connector is movably sleeved on the outer periphery of the lower threaded rod; the upper core connector is fixedly installed in the upper part of the upper conversion chamber, and the upper core connector is movably sleeved on the outer periphery of the upper threaded rod.

[0008] As one possible implementation, the observation system includes a first piezometer, a second piezometer, and a flow meter connected to the terminal device; the first piezometer is used to collect the first pressure data and transmit it to the terminal device; the second piezometer is used to collect the second pressure data and transmit it to the terminal device; and the flow meter is used to collect the flow data and transmit it to the terminal device.

[0009] As one possible implementation, both the upper packer and the lower packer are cylindrical and coaxially arranged within the pumping hole; the terminal device is also used to: determine the first drawdown of the test layer based on the first pressure data, and adjust the power of the variable frequency pump based on the first drawdown and the first pressure data.

[0010] As one possible implementation, the terminal device is also used to: determine the second drawdown of the upper part of the test layer based on the second pressure data; and calculate the permeability coefficient based on the midpoint depth of the upper packer, the lowering depth of the second piezometer, the second pressure data, the first drawdown, the radius of the pumping hole, the flow rate data of the outlet pipeline, the second drawdown, and the installation position information of the upper packer and the lower packer.

[0011] As one possible implementation, the installation position information of the upper packer and the lower packer includes the midpoint depth of the upper packer and the distance between the midpoints of the upper packer and the lower packer; the terminal device is further configured to: determine the original water level height based on the midpoint depth of the upper packer, the lowering depth of the second piezometer, and the second pressure data; and calculate the permeability coefficient based on the original water level height, the first drawdown, the radius of the pumping hole, the flow rate data of the outlet pipeline, the second drawdown, and the distance between the midpoints of the upper packer and the lower packer.

[0012] Secondly, embodiments of the present invention also provide a method for calculating the permeability coefficient, applied to the terminal equipment of the pumping device described in the first aspect above, comprising: determining a second drawdown at the upper part of the test layer based on the second pressure data; and calculating the permeability coefficient based on the midpoint depth of the upper packer, the lowering depth of the second piezometer, the second pressure data, the first drawdown, the radius of the pumping hole, the flow rate data of the outlet pipeline, the second drawdown, and the installation position information of the upper packer and the lower packer, respectively.

[0013] As one possible implementation, the installation location information includes the midpoint depth of the upper packer and the distance between the midpoints of the upper and lower packers; based on the midpoint depth of the upper packer, the lowering depth of the second piezometer, the second pressure data, the first drawdown, the radius of the pumping hole, the flow rate data of the outlet pipeline, the second drawdown, and the respective installation location information of the upper and lower packers, a permeability coefficient is calculated, including: determining the initial water level height based on the midpoint depth of the upper packer, the lowering depth of the second piezometer, and the second pressure data; and calculating the permeability coefficient based on the initial water level height, the first drawdown, the radius of the pumping hole, the flow rate data of the outlet pipeline, the second drawdown, and the distance between the midpoints of the upper and lower packers.

[0014] As one possible implementation, based on the original water level, the first drawdown, the radius of the pumping hole, the flow rate data of the outlet pipe, the second drawdown, and the distance between the midpoint of the upper packer and the midpoint of the lower packer, the permeability coefficient is calculated, including: when the upper packer is located at the interface between the unconfined aquifer and the confined aquifer, if the first permeability coefficient of the unconfined aquifer is known, then based on the original water level, the first drawdown, the radius of the pumping hole, the flow rate data of the outlet pipe, the second drawdown, and the distance between the midpoint of the upper packer and the midpoint of the lower packer, the second permeability coefficient of the confined aquifer is iteratively calculated; when the upper packer is located within the aquifer, based on the original water level, the first drawdown, the radius of the pumping hole, the flow rate data of the outlet pipe, the second drawdown, and the distance between the midpoint of the upper packer and the midpoint of the lower packer, the third permeability coefficient of the aquifer is iteratively calculated.

[0015] The present invention provides a pumping device and a method for calculating the permeability coefficient. It adopts an innovative isolation system and sealing system to achieve reliable hydraulic isolation. Combined with a pumping control system and a monitoring system, it can conduct pumping tests and greatly reduce the disturbance to the surrounding groundwater while achieving deep drawdown pumping. It is suitable for testing multi-layer aquifers. At the same time, it improves the permeability coefficient calculation method, making the permeability coefficient calculation results more accurate.

[0016] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention are realized and obtained in accordance with the structures particularly pointed out in the description, claims and drawings.

[0017] 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

[0018] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the structure of a water pumping device according to an embodiment of the present invention;

[0020] Figure 2 This is a cross-sectional schematic diagram of the pumping device in an embodiment of the present invention;

[0021] Figure 3 This is a schematic diagram of the seepage model in an embodiment of the present invention;

[0022] Figure 4 This is a flowchart illustrating a method for calculating the permeability coefficient in an embodiment of the present invention.

[0023] Icons: 100-Packing system; 200-Pumping control system; 300-Sealing system; 400-Observation system; 1-Upper packer; 2-Lower packer; 3-Packer control line; 4-Packer pressurization device; 5-Terminal equipment; 6-Variable frequency pump; 7-Check valve; 8-Outlet line; 9-Power output line; 10-Power input line; 11-Lower internal connector; 12-Lower lead screw; 13-Lower core connector; 1 4-Lower conversion chamber; 15-Lower adapter; 16-Aluminum-plastic pipe; 17-Sealing device; 18-Upper adapter; 19-Upper conversion chamber; 20-Upper core connector; 21-Upper threaded rod; 22-Upper inner connector; 23-First piezometer; 24-First piezometer data cable; 25-Second piezometer; 26-Second piezometer data cable; 27-Flow meter; 28-Flow meter data cable; 81-First pipe section; 82-Fifth pipe section. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] Currently, conventional pumping tests in existing technologies mostly employ the full-bore pumping method. Common theoretical calculation formulas (such as the Theis formula and the Jacob formula) do not fully consider the effects of cross-layer seepage between multiple aquifers. The main problems with this technology are as follows: 1) Existing formulas do not adequately consider cross-layer seepage, leading to inaccurate permeability coefficient calculations and affecting engineering design and safety assessments; 2) The drop in water level in the upper aquifer during pumping may cause large-scale ground subsidence, degradation of surface vegetation, and other environmental problems; 3) Full-bore pumping cannot achieve large drawdown depths for a specific aquifer, making it difficult to simulate actual engineering conditions (such as deep dewatering after foundation pit excavation).

[0026] Based on this, the present invention provides a pumping device and a method for calculating the permeability coefficient, which can alleviate the above-mentioned problems existing in related technologies.

[0027] To facilitate understanding of this embodiment, a water pumping device disclosed in this invention will first be described in detail, see [link to relevant documentation]. Figure 1 and Figure 2 As shown, the pumping device may include: a sealing system 100, a pumping control system 200, a sealing system 300, and an observation system 400;

[0028] The packer system 100 includes an upper packer 1, a lower packer 2, and a packer pressurization device 4; the upper packer 1, the lower packer 2, and the sealing system 300 are all vertically installed inside the pumping hole; the upper packer 1 and the lower packer 2 are both located underground and are spaced apart vertically; the upper packer 1 is connected to the packer pressurization device 4 and the lower packer 2 respectively through the packer control pipeline 3; the upper packer 1 and the lower packer 2 can be made of natural rubber or synthetic rubber; the packer control pipeline 3 can withstand a pressure greater than 3 MPa; the packer pressurization device 4 has a switching device that can apply and release the pressure of the packers (i.e., the upper packer 1 and the lower packer 2).

[0029] The pumping control system 200 includes terminal equipment 5 and variable frequency pump 6; the variable frequency pump 6 is fixedly installed on the upper part of the lower packer 2; the outlet end of the variable frequency pump 6 is connected to the ground through the outlet pipe 8; wherein, the variable frequency pump 6 can use a 380V three-phase power input.

[0030] The sealing system 300 includes a lower conversion chamber 14, an upper conversion chamber 19, a connecting pipe, and a sealing device 17. Both the lower conversion chamber 14 and the upper conversion chamber 19 are hollow structures. The upper part of the lower conversion chamber 14 is fixedly connected to the lower part of the upper packer 1, and the lower part of the upper conversion chamber 19 is fixedly connected to the upper part of the upper packer 1 through the sealing device 17. The first part of the outlet pipe 8 passes through the lower conversion chamber 14, the upper packer 1, the sealing device 17, and the upper packer 1. The lower part of the lower conversion chamber 14 is fitted around the outer periphery of the second part of the outlet pipe 8, and the upper part of the upper conversion chamber 19 is fitted around the outer periphery of the third part of the outlet pipe 8. The sealing device 17 can be made of stainless steel and is used to connect the upper packer 1 and the upper conversion chamber 19. The middle part can be filled with resin. Specifically, the sealing device 17 can be connected to the upper part of the upper packer 1 through a screw thread to achieve a fixed connection between the sealing device 17 and the upper part of the upper packer 1.

[0031] The observation system 400 is used to collect the first pressure data of the test layer, the second pressure data of the upper part of the test layer, and the flow data of the outlet pipe 8, respectively; the test layer is located between the upper packer 1 and the lower packer 2; the terminal equipment 5 is connected to the observation system 400 and the variable frequency water pump 6, respectively, and is used to control the variable frequency water pump 6 to pump water based on the first pressure data.

[0032] The pumping device provided in this embodiment of the invention adopts an innovative isolation and sealing system to achieve reliable hydraulic isolation. It works in conjunction with a pumping control system and a monitoring system to conduct pumping tests. It greatly reduces the disturbance to the surrounding groundwater while achieving deep drawdown pumping and is suitable for testing multi-layer aquifers.

[0033] As one possible implementation method, see Figure 1 and Figure 2As shown, the observation system 400 may include a first piezometer 23, a second piezometer 25, and a flow meter 27 connected to the terminal device 5; the first piezometer 23 is used to collect first pressure data and transmit it to the terminal device 5; the second piezometer 25 is used to collect second pressure data and transmit it to the terminal device 5; and the flow meter 27 is used to collect flow data and transmit it to the terminal device 5.

[0034] by Figure 2 and Figure 3 For example, terminal device 5 can adopt PID control and data storage terminal; first piezometer 23 (lowering depth is...) The first piezometer data cable 24 connects to the terminal device 5, allowing for continuous measurement of the pressure data of the test layer (the measured pressure is...). The pressure data measured by the first piezometer 23 is transmitted to the terminal device 5 via the first piezometer data line 24; wherein, the lowering depth of the first piezometer 23 is... The depth of the upper packer 1 can be determined by the length of the lowering of the first piezometer data line 24, or by the relative position of the first piezometer 23 and the upper packer 1; the lowering depth of the upper packer 1 can be determined by the length of the outlet pipe 8.

[0035] Following the previous example, with Figure 2 and Figure 3 For example, the second piezometer 25 (lowered to a depth of...) () Connected to terminal device 5 via second piezometer data cable 26, it can be used to: continuously measure pressure data of the upper part of the test layer (the measured pressure is...) The pressure data measured by the second piezometer 25 is transmitted to the terminal device 5 via the second piezometer data line 26; wherein, the lowering depth of the second piezometer 25 is... The length of the second piezometer data line 26 can be determined.

[0036] Following the previous example, with Figure 2 For example, the flow meter 27 is connected to the terminal device 5 via the flow meter data line 28, and can be used to: record the flow rate of the water outlet pipe 8 (the flow rate is denoted as Q), and transmit the flow rate data recorded by the flow meter 27 to the terminal device 5 via the flow meter data line 28.

[0037] As one possible implementation method, see Figure 1 and Figure 2As shown, the outlet pipe 8 may include a first pipe section 81, a second pipe section, a third pipe section, a fourth pipe section, and a fifth pipe section 82 arranged sequentially from bottom to top; the pumping control system 200 also includes a one-way valve 7; the lower end of the first pipe section 81 is connected to the outlet end of the variable frequency water pump 6 through the one-way valve 7, the upper end of the first pipe section 81 is fixedly connected to the lower end of the second pipe section, the upper end of the second pipe section is fixedly connected to the lower end of the connecting pipe, the upper end of the third pipe section is fixedly connected to the lower end of the fourth pipe section, the upper end of the fourth pipe section is fixedly connected to the lower end of the fifth pipe section 82, and the fifth pipe section 82 extends from its lower end to the ground; the lower part of the lower conversion chamber 14 is fitted around the outer periphery of the second pipe section; the third pipe section passes through the upper packer 1 and the sealing device 17; the third pipe section uses a connecting pipe; the upper part of the upper conversion chamber 19 is fitted around the outer periphery of the fourth pipe section.

[0038] Following the previous example, with Figure 2 For example, the outlet pipe 8 may have a section located underground (i.e., the first pipe section 81) and another section connected to the ground (i.e., the fifth pipe section 82). The flow meter 27 may be installed on the part of the fifth pipe section 82 that is located above ground. The first pipe section 81 is used to connect the one-way valve 7 to the outlet end of the variable frequency water pump 6, and the fifth pipe section 82 is used to extend from its lower end to the ground and connect to the flow meter 27. The one-way valve 7 is installed between the variable frequency water pump 6 and the first pipe section 81, and only allows the water to flow upward in one direction.

[0039] As one possible implementation method, see Figure 1 and Figure 2 As shown, the second pipe section can use a lower threaded rod 12, the connecting pipe can use an aluminum-plastic pipe 16, and the fourth pipe section can use an upper threaded rod 21. Based on this, the sealing device 17 can also include a lower inner connector 11, a lower threaded rod 12, a lower core connector 13, a lower adapter 15, an upper adapter 18, an upper threaded rod 21, an upper core connector 20, and an upper inner connector 22. The upper end of the first pipe section is fixedly connected to the lower end of the lower threaded rod 12 through the lower inner connector 11, and the upper end of the lower threaded rod 12 is connected to the lower adapter 18 through the lower adapter 19. 5 is fixedly connected to the lower end of the aluminum-plastic pipe 16; the upper end of the aluminum-plastic pipe 16 is fixedly connected to the lower end of the upper threaded rod 21 through the upper adapter 18, and the upper end of the upper threaded rod 21 is fixedly connected to the lower end of the fifth pipe section through the upper inner connector 22; the lower core connector 13 is fixedly installed in the lower part of the lower conversion chamber 14, and the lower core connector 13 is movably sleeved on the outer circumference of the lower threaded rod 12; the upper core connector 20 is fixedly installed in the upper part of the upper conversion chamber 19, and the upper core connector 20 is movably sleeved on the outer circumference of the upper threaded rod 21.

[0040] Following the previous example, with Figure 2For example, the lower inner connector 11 can be used to connect the first pipe section 81 and the lower threaded rod 12; the lower threaded rod 12 can be used to connect the first pipe section 81 and the aluminum-plastic pipe 16, and is used to install and fix the lower core connector 13 (so that the lower core connector 13 can be screwed into the predetermined position); the lower core connector 13 can be used to fix the relative position of the lower threaded rod 12 and the lower conversion chamber 14. After the lower adapter 15 is installed, the lower core connector 13 is screwed into the lower part of the lower threaded rod 12, and finally screwed into the lower part of the lower conversion chamber 14.

[0041] Following the previous example, with Figure 2 For example, the lower conversion chamber 14 is installed at the lower part of the lower packer 2 and can be used to connect and fix the upper packer 1 and the lower screw 12. The lower conversion chamber 14 can be hollow and open on one side to facilitate the installation of the lower adapter 15 and the passage of related lines (such as the second piezometer data line 26 and the power output line 9 for connecting the terminal equipment 5 and the variable frequency water pump 6).

[0042] Following the previous example, with Figure 2 For example, the lower adapter 15 can be used to connect the aluminum-plastic pipe 16 and the lower screw 12; the aluminum-plastic pipe 16, as part of the water outlet pipe 8, is installed from the lower conversion chamber 14 to the upper conversion chamber 19 and is fixed by the sealing device 17; since the aluminum-plastic pipe 16 has a certain strength and can be appropriately deformed, it is very suitable for use in pumping devices; the main function of the aluminum-plastic pipe 16 is to pass water, and it needs to be tightly bonded to the surrounding sealant when passing through the sealing device 17. After exiting the sealing device 17, it also needs to have a certain deformation and bending function to ensure that the upper screw 21 and the lower screw 12 can be centered.

[0043] Following the previous example, with Figure 2 For example, the upper adapter 18 can be used to connect the aluminum-plastic pipe 16 and the upper screw 21; the upper conversion chamber 19 is installed on the upper part of the sealing device 17 and can be used to connect the fixed sealing device 17 and the upper screw 21; the upper conversion chamber 19 can adopt a hollow structure and have an opening on one side to facilitate the installation of the upper adapter 18 and the passage of related lines (such as the second piezometer data line 26 and the power output line 9 for connecting the terminal equipment 5 and the variable frequency water pump 6).

[0044] Following the previous example, with Figure 2 For example, the upper core connector 20 can be used to fix the relative position of the upper lead screw 21 and the upper conversion chamber 19. After the upper adapter 18 is installed, the upper core connector 20 is screwed into the upper part of the upper lead screw 21 and finally screwed into the upper part of the upper conversion chamber 19.

[0045] Following the previous example, with Figure 2For example, the upper screw 21 can be used to connect the fifth pipe section 82 and the aluminum-plastic pipe 16, and to install and fix the upper core connector 20 (so that the upper core connector 20 can be screwed into the predetermined position); the upper inner connector 22 can be used to connect the fifth pipe section 82 and the upper screw 21.

[0046] As one possible implementation method, see Figure 1 and Figure 2 As shown, both the upper packer 1 and the lower packer 2 can be cylindrical and coaxially arranged inside the pumping hole; based on this, the terminal device 5 can also be used to: determine the first drawdown of the test layer (denoted as ) based on the first pressure data. The power of the variable frequency pump 6 is adjusted based on the first water level drawdown and the first pressure data.

[0047] Following the previous example, with Figure 2 For example, the diameters of the upper packer 1 and the lower packer 2 can be selected according to the diameter of the borehole to be tested (i.e., the pumping hole); the terminal device 5 is connected to an external power source via the power input line 10 and to the variable frequency water pump 6 via the power output line 9; the terminal device 5 can adopt PID control and data storage terminal, specifically used to receive and store the first pressure data, second pressure data and flow data collected by the observation system 400, and to set the drawdown of the test layer (denoted as ) according to the first pressure data. This is used as a drawdown parameter, and then based on the set drawdown parameter... The power output frequency is continuously adjusted based on the power input frequency and the first pressure data fed back by the first piezometer 23, so as to adjust the power of the variable frequency water pump 6.

[0048] As one possible implementation method, see Figures 1 to 3 As shown, terminal device 5 can also be used to: determine the second drawdown (denoted as) above the test layer based on the second pressure data. ); based on the depth of the midpoint of the upper packer 1 (denoted as ); The lowering depth of the second piezometer 25 (denoted as...) ), second pressure data, first water level drawdown (denoted as ), ), radius of the pumping hole (denoted as The flow rate data of the outlet pipe 8, the second water level drawdown, and the installation position information of the upper packer 1 and the lower packer 2 are used to calculate the permeability coefficient.

[0049] For example, the installation position information of the upper packer 1 and the lower packer 2 may include the midpoint depth of the upper packer 1 and the distance between the midpoint of the upper packer 1 and the midpoint of the lower packer 2; based on this, the terminal device 5 can determine the first water level drawdown of the known test layer. and the second drawdown above the test layer In this case, the depth can be based on the midpoint depth of the upper packer 1. The lowering depth of the second piezometer 25 And the second pressure data, to determine the original water level height (denoted as ). Based on the original water level height First water level drawdown Radius of the water pump hole Flow data of outlet pipe 8 and second water level drawdown And the distance between the midpoint of the upper packer 1 and the midpoint of the lower packer 2 (denoted as...). ), and perform permeability coefficient calculation.

[0050] The calculation of permeability coefficient can be divided into the following two cases:

[0051] (1) When the upper packer 1 is located at the interface between the unconfined layer and the confined aquifer, if the first permeability coefficient of the unconfined layer is known, the second permeability coefficient of the confined aquifer is iteratively calculated based on the original water level height, the first drawdown, the radius of the pumping hole, the flow rate data of the outlet pipe 8, the second drawdown, and the distance between the midpoint of the upper packer 1 and the midpoint of the lower packer 2.

[0052] (2) When the upper packer 1 is located in the aquifer, the third permeability coefficient of the aquifer is calculated iteratively based on the original water level height, the first drawdown, the radius of the pumping hole, the flow rate data of the outlet pipe 8, the second drawdown, and the distance between the midpoint of the upper packer 1 and the midpoint of the lower packer 2.

[0053] For ease of understanding, the pumping device and permeability coefficient calculation method provided in the embodiments of the present invention are described exemplarily below with specific applications.

[0054] The design of the pumping device takes into account the cross-layer seepage of the upper water body, which can make the calculation method of the pumping test more scientific.

[0055] The principle of using a pumping device for pumping tests and permeability coefficient calculation is as follows: drilling; installing the pumping equipment and packer; pressurizing the packer to isolate the hydraulic connection between the upper and lower layers; starting the pumping equipment based on PID control, performing the pumping test according to the set drawdown, and simultaneously recording the pumping flow rate, the drawdown of the test layer, and the drawdown of the upper layer; and using the theoretical formula considering stratified seepage to calculate the permeability coefficient of the target soil and rock layer.

[0056] Following the previous example, with Figure 1 and Figure 2 For example, a stratified pumping device can mainly include a containment system 100, a pumping control system 200, a sealing system 300, and an observation system 400.

[0057] 1) The packer system 100 mainly includes: upper packer 1, lower packer 2, packer control pipeline 3 and packer pressurization device 4.

[0058] 2) The pumping control system 200 mainly includes: terminal equipment 5 (using PID control and data storage terminal), variable frequency water pump 6, water outlet pipeline 8, one-way valve 7, power output line 9, and power input line 10.

[0059] Among them, terminal device 5 can be used to: determine the water level drawdown parameters according to the set parameters. The power output frequency is continuously adjusted based on the data fed back from the first piezometer 23 to adjust the power of the variable frequency water pump 6, and the data collected by the first piezometer 23, the second piezometer 25, and the flow meter 27 during the test are recorded at the set recording time intervals.

[0060] 3) The sealing system 300 mainly includes: lower inner connector 11, lower screw 12, lower core connector 13, lower conversion chamber 14, lower adapter 15, aluminum-plastic pipe 16, sealing device 17, upper adapter 18, upper conversion chamber 19, upper core connector 20, upper screw 21, and upper inner connector 22.

[0061] 4) The observation system 400 mainly includes: a first piezometer 23, a first piezometer data line 24, a second piezometer 25, a second piezometer data line 26, a flow meter 27, and a flow meter data line 28.

[0062] The steps for conducting a pumping test using the above-mentioned pumping device are as follows:

[0063] Step S1: After drilling to the target layer, the packer system 100 is lowered and pressurized to expand the upper packer 1 and the lower packer 2 to isolate the target aquifer from the hydraulic connection with other aquifers.

[0064] Step S2: Observe and record the initial pressure data of the second piezometer 25 and the first piezometer 23.

[0065]

[0066] In the formula: Represents the original water level height, which is the distance from the midpoint of the upper packer 1 to the original water level surface, in meters; The depth of the midpoint of the upper packer 1 is represented by the length of the lowering of the upper structure of the upper packer 1, which can be obtained by adding the lengths of the corresponding components on site, and the unit is m; The lowering depth of the second piezometer 25 is represented in meters (m). This represents the initial pressure measured by the second piezometer 25, in MPa.

[0067] Start the pumping equipment and draw down to the set depth. During pumping, the following data is recorded synchronously at set time intervals:

[0068] 1) The pressure measured by the first piezometer ( ):

[0069]

[0070] In the formula: The water level drawdown of the test layer (confined water) is expressed in meters (m). This represents the initial pressure measured by the first piezometer 23, in MPa; This represents the pressure measured by the first piezometer 23 after pumping, in MPa;

[0071] 2) Drawdown of the upper water level ( ):

[0072] but

[0073] In the formula: Represents the drawdown of the upper (groundwater) level, in meters (m). This represents the initial pressure measured by the second piezometer 25, in MPa. This represents the pressure measured by the second piezometer 25 after pumping, in MPa.

[0074] 3) Pumping flow rate ( The flow rate was directly measured by flow meter 27, and the unit is... ).

[0075] Step S3: Data processing.

[0076] (a) Establishment Figure 3 The seepage model shown has a two-layer structure:

[0077] Using packer 1 as the boundary, the seepage model is divided into upper and lower layers. The upper layer is the part above packer 1 (which can be considered as a shallow water layer), and the lower layer is the test layer between packer 1 and packer 2 (which can be considered as a confined water layer, i.e.) Figure 2 (The confined aquifer in the middle).

[0078] Therefore, the total pumping volume Seepage from the two layers mentioned above, including the pumping volume of the unconfined layer. Pumping volume of confined aquifer , .

[0079] (II) Calculation of permeability coefficient:

[0080] Permeability coefficient of upper groundwater The calculation is performed using the Djubuyi formula as follows:

[0081]

[0082]

[0083] Derivation:

[0084]

[0085] Permeability coefficient of the lower confined aquifer The calculation is performed using the Djubuyi formula as follows:

[0086]

[0087]

[0088] In the above formula: Let be a known variable, representing the steady-state pumping flow rate; This indicates the drawdown of the upper (groundwater) level, in meters (m). This indicates the drawdown of the test layer (confined water), in meters (m). The thickness of the pressure layer is represented by the distance from the midpoint of the upper packer 1 to the midpoint of the lower packer 2, in meters; H represents the original water level. Indicates the radius of influence of the diving, in meters; Indicates the radius of influence of confined water, in meters; Let be a known variable, representing the radius of the pumping hole (i.e., the radius of the borehole), in meters.

[0089] 1) When the upper packer 1 is located at the interface between the upper and lower aquifers (the midpoint of the upper packer 1 must be placed on the boundary line between the upper and lower aquifers), ,and Given:

[0090] The calculation formula is:

[0091] (1)

[0092] make:

[0093]

[0094]

[0095] All quantities in the formula are known quantities;

[0096] Formula (1) simplifies to:

[0097]

[0098] in, , These are known constants;

[0099] Iterative solution:

[0100] a) Selecting initial values Recommended value: ;

[0101] b) Establish an iterative formula:

[0102]

[0103] c) Set convergence conditions:

[0104]

[0105] To allow for error, it is recommended to take... ;

[0106] d) Iterate using the established iterative formula until the convergence condition is met, and finally obtain... This is the permeability coefficient we are looking for.

[0107] Result verification: Substitute the obtained permeability coefficient into the original formula to verify whether the calculation error meets the engineering accuracy requirements.

[0108] 2) When the upper and lower layers are located in the same soil layer (the placement of the upper packer 1 is not specified), :

[0109] Formula (1) , use The substitution yields:

[0110] (2)

[0111] Define the core function f(K):

[0112] The original formula (2) is rearranged as follows: :

[0113]

[0114] beg derivative :

[0115] because It is a composite function, and its derivative needs to be calculated by decomposing it into the following sub-terms:

[0116] a) Record ,but ;

[0117] b) Record ,but ;

[0118] c) Record ,but ;

[0119] d) Record ,but ;

[0120] final derivative for:

[0121]

[0122] Using Newton's iterative calculation:

[0123] a) Select initial value The value is taken according to the actual physical meaning of the variable: ;

[0124] b) Establish an iterative formula:

[0125]

[0126] c) Set convergence conditions:

[0127]

[0128] To allow for error, it is recommended to take... ;

[0129] d) Iterate using the established iterative formula until the convergence condition is met, and finally obtain... This is the permeability coefficient we are looking for.

[0130] Result verification: Substitute the obtained permeability coefficient into the original formula to verify whether the calculation error meets the engineering accuracy requirements.

[0131] After the test is completed, the pressure of the upper packer 1 and the lower packer 2 is released by the packer pressurization device 4. If the next test is to be carried out, the test and permeability coefficient calculation are repeated according to the above steps S1 to S3.

[0132] The core improvements of the above-mentioned pumping device and permeability coefficient calculation method are mainly as follows: 1) Proposing a cross-layer seepage theoretical calculation model suitable for stratified pumping to achieve accurate permeability coefficient calculation; 2) The sealing system 100 adopts a high-pressure rubber packer and its pressurization device to achieve reliable hydraulic isolation; 3) Integrating a PID controller and data storage terminal, a variable frequency pump 6 and a multi-point piezometer to achieve automatic control of the pumping process and synchronous data recording; 4) Providing a complete process method for drilling, sealing, pumping, recording and calculation, which is suitable for multi-layer aquifer testing.

[0133] Compared with existing technologies, the above-mentioned pumping device and permeability coefficient calculation method have the following significant advantages:

[0134] (1) By isolating different aquifers through the sealing system 100 and combining the layered seepage theory model, the hydraulic influence of each layer is effectively separated, making the calculation of the permeability coefficient more scientific and accurate.

[0135] (2) Layered pumping only affects the target aquifer, avoiding a significant drop in the water level of the upper aquifer, thereby reducing environmental risks such as land subsidence.

[0136] (3) For highly permeable strata, deep dewatering can be achieved in the target layer to better simulate actual engineering conditions (such as foundation pit dewatering).

[0137] (4) By using PID control and automatic data recording, manual intervention is reduced, and experimental efficiency and data reliability are improved.

[0138] (5) In response to the pain point that traditional packers have difficulty in achieving both sealing and adaptability, new materials and structural design have been adopted to enable various pipelines to pass through smoothly and ensure that the overall sealing effect of the packer meets the standards. At the same time, the detachable structural design can be flexibly adapted to packers of different diameters, greatly improving the versatility and reusability of the pumping device.

[0139] This invention also provides a method for calculating the permeability coefficient, see [link to relevant documentation]. Figure 1 and Figure 4 As shown, this method can be applied to the terminal device 5 of the above-mentioned pumping device, and the method may include the following steps:

[0140] Step S402: Determine the second drawdown of the upper part of the test layer based on the second pressure data.

[0141] Step S404: Based on the midpoint depth of the upper packer 1, the lowering depth of the second piezometer 25, the second pressure data, the first drawdown, the radius of the pumping hole, the flow rate data of the outlet pipe 8, the second drawdown, and the installation position information of the upper packer 1 and the lower packer 2, the permeability coefficient is calculated.

[0142] The above-mentioned method for calculating the permeability coefficient improves the calculation method and makes the calculation results more accurate.

[0143] As one possible implementation, the aforementioned installation location information may include the midpoint depth of the upper packer 1 and the distance between the midpoint of the upper packer 1 and the midpoint of the lower packer 2. Based on this, step S404 (i.e., calculating the permeability coefficient based on the midpoint depth of the upper packer 1, the lowering depth of the second piezometer 25, the second pressure data, the first drawdown, the radius of the pumping hole, the flow rate data of the outlet pipe 8, the second drawdown, and the respective installation location information of the upper packer 1 and the lower packer 2) may include: determining the original water level height based on the midpoint depth of the upper packer 1, the lowering depth of the second piezometer 25, and the second pressure data; and calculating the permeability coefficient based on the original water level height, the first drawdown, the radius of the pumping hole, the flow rate data of the outlet pipe 8, the second drawdown, and the distance between the midpoint of the upper packer 1 and the midpoint of the lower packer 2.

[0144] As one possible implementation, the above-mentioned step of calculating the permeability coefficient based on the original water level height, the first drawdown, the radius of the pumping hole, the flow rate data of the outlet pipe 8, the second drawdown, and the distance between the midpoint of the upper packer 1 and the midpoint of the lower packer 2 may include: (1) when the upper packer 1 is located at the interface between the unconfined aquifer and the confined aquifer, if the first permeability coefficient of the unconfined aquifer is known, then the second permeability coefficient of the confined aquifer is iteratively calculated based on the original water level height, the first drawdown, the radius of the pumping hole, the flow rate data of the outlet pipe 8, the second drawdown, and the distance between the midpoint of the upper packer 1 and the midpoint of the lower packer 2; (2) when the upper packer 1 is located within the aquifer, the third permeability coefficient of the aquifer is iteratively calculated based on the original water level height, the first drawdown, the radius of the pumping hole, the flow rate data of the outlet pipe 8, the second drawdown, and the distance between the midpoint of the upper packer 1 and the midpoint of the lower packer 2.

[0145] The permeability coefficient calculation method provided in this embodiment of the invention has the same implementation principle and technical effect as the aforementioned pumping device embodiment. For the sake of brevity, any parts not mentioned in the method embodiment can be referred to the corresponding content in the aforementioned device embodiment.

[0146] Unless otherwise specifically stated, the relative steps, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of the invention.

[0147] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a processor-executable, non-volatile, computer-readable storage medium. Based on this understanding, the technical solution of this invention, essentially, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0148] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for 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, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0149] Finally, it should be noted that the above-described embodiments are merely specific implementations of the present invention, used to illustrate the technical solutions of the present invention, and not to limit it. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments within the technical scope disclosed in the present invention, or make equivalent substitutions for some of the technical features; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A water pumping device, characterized in that, include: Containment system, pumping control system, sealing system, and monitoring system; The packing system includes an upper packer, a lower packer, and a packer pressurization device; the upper packer, the lower packer, and the sealing system are all vertically installed inside the pumping hole; the upper packer and the lower packer are both located underground and are spaced apart vertically; the upper packer is connected to the packer pressurization device and the lower packer respectively through a packer control pipeline; The pumping control system includes terminal equipment and a variable frequency water pump; the variable frequency water pump is fixedly installed on the upper part of the lower packer; the outlet end of the variable frequency water pump is connected to the ground through an outlet pipeline; The sealing system includes a lower conversion chamber, an upper conversion chamber, a connecting pipe, and a sealing device; both the lower and upper conversion chambers are hollow structures; the upper part of the lower conversion chamber is fixedly connected to the lower part of the upper packer, and the lower part of the upper conversion chamber is fixedly connected to the upper part of the upper packer through the sealing device; the first part of the outlet pipe passes through the lower conversion chamber, the upper packer, the sealing device, and the upper packer; the lower part of the lower conversion chamber is fitted around the outer periphery of the second part of the outlet pipe, and the upper part of the upper conversion chamber is fitted around the outer periphery of the third part of the outlet pipe; The observation system is used to collect the first pressure data of the test layer, the second pressure data of the upper part of the test layer, and the flow rate data of the outlet pipeline, respectively; the test layer is located between the upper packer and the lower packer; the terminal equipment is connected to the observation system and the variable frequency water pump, respectively, and is used to control the variable frequency water pump to pump water based on the first pressure data; The water outlet pipeline includes a first pipe section, a second pipe section, a third pipe section, a fourth pipe section, and a fifth pipe section arranged sequentially from bottom to top; the pumping control system also includes a one-way valve; the lower end of the first pipe section is connected to the outlet end of the variable frequency water pump through the one-way valve; the upper end of the first pipe section is fixedly connected to the lower end of the second pipe section; the upper end of the second pipe section is fixedly connected to the lower end of the connecting pipe; the upper end of the third pipe section is fixedly connected to the lower end of the fourth pipe section; the upper end of the fourth pipe section is fixedly connected to the lower end of the fifth pipe section; the fifth pipe section extends from its lower end to the ground; the lower part of the lower conversion chamber is sleeved around the outer periphery of the second pipe section; the third pipe section passes through the upper packer and the sealing device; the third pipe section uses the connecting pipe; the upper part of the upper conversion chamber is sleeved around the outer periphery of the fourth pipe section; The second pipe section uses a lower threaded rod, the connecting pipe uses an aluminum-plastic pipe, and the fourth pipe section uses an upper threaded rod; the sealing device further includes a lower inner connector, the lower threaded rod, a lower core connector, a lower adapter, an upper adapter, the upper threaded rod, the upper core connector, and an upper inner connector; the upper end of the first pipe section is fixedly connected to the lower end of the lower threaded rod through the lower inner connector, and the upper end of the lower threaded rod is fixedly connected to the lower end of the aluminum-plastic pipe through the lower adapter; the upper end of the aluminum-plastic pipe is fixedly connected to the lower end of the upper threaded rod through the upper adapter, and the upper end of the upper threaded rod is fixedly connected to the lower end of the fifth pipe section through the upper inner connector; The lower core connector is fixedly installed at the lower part of the lower conversion chamber, and the lower core connector is movably sleeved on the outer periphery of the lower lead screw; the upper core connector is fixedly installed at the upper part of the upper conversion chamber, and the upper core connector is movably sleeved on the outer periphery of the upper lead screw.

2. The pumping device according to claim 1, characterized in that, The observation system includes a first piezometer, a second piezometer, and a flow meter connected to the terminal device; the first piezometer is used to collect the first pressure data and transmit it to the terminal device; the second piezometer is used to collect the second pressure data and transmit it to the terminal device; and the flow meter is used to collect the flow data and transmit it to the terminal device.

3. The pumping device according to claim 2, characterized in that, Both the upper packer and the lower packer are cylindrical and coaxially arranged inside the pumping hole; the terminal device is also used to: determine the first drawdown of the test layer based on the first pressure data, and adjust the power of the variable frequency pump based on the first drawdown and the first pressure data.

4. The pumping device according to claim 3, characterized in that, The terminal device is also used to: determine the second drawdown of the upper part of the test layer based on the second pressure data; and to calculate the permeability coefficient based on the midpoint depth of the upper packer, the lowering depth of the second piezometer, the second pressure data, the first drawdown, the radius of the pumping hole, the flow rate data of the outlet pipeline, the second drawdown, and the installation position information of the upper packer and the lower packer.

5. The pumping device according to claim 4, characterized in that, The installation position information of the upper packer and the lower packer includes the midpoint depth of the upper packer and the distance between the midpoints of the upper packer and the lower packer; the terminal device is also used to: determine the original water level height based on the midpoint depth of the upper packer, the lowering depth of the second piezometer, and the second pressure data; and calculate the permeability coefficient based on the original water level height, the first drawdown, the radius of the pumping hole, the flow rate data of the outlet pipeline, the second drawdown, and the distance between the midpoints of the upper packer and the lower packer.

6. A method for calculating the permeability coefficient, characterized in that, Terminal equipment applied to the pumping device according to any one of claims 3-5, comprising: The second drawdown of the upper part of the test layer is determined based on the second pressure data; The permeability coefficient is calculated based on the midpoint depth of the upper packer, the lowering depth of the second piezometer, the second pressure data, the first drawdown, the radius of the pumping hole, the flow rate data of the outlet pipeline, the second drawdown, and the installation position information of the upper and lower packers.

7. The method for calculating the permeability coefficient according to claim 6, characterized in that, The installation location information includes the midpoint depth of the upper packer and the distance between the midpoints of the upper and lower packers. Based on the midpoint depth of the upper packer, the lowering depth of the second piezometer, the second pressure data, the first drawdown, the radius of the pumping hole, the flow rate data of the outlet pipeline, the second drawdown, and the installation location information of the upper and lower packers, a permeability coefficient is calculated, including: determining the initial water level based on the midpoint depth of the upper packer, the lowering depth of the second piezometer, and the second pressure data; and calculating the permeability coefficient based on the initial water level, the first drawdown, the radius of the pumping hole, the flow rate data of the outlet pipeline, the second drawdown, and the distance between the midpoints of the upper and lower packers.

8. The method for calculating the permeability coefficient according to claim 7, characterized in that, Based on the original water level, the first drawdown, the radius of the pumping hole, the flow rate data of the outlet pipeline, the second drawdown, and the distance between the midpoint of the upper packer and the midpoint of the lower packer, the permeability coefficient is calculated, including: When the upper packer is located at the interface between the unconfined aquifer and the confined aquifer, if the first permeability coefficient of the unconfined aquifer is known, the second permeability coefficient of the confined aquifer is iteratively calculated based on the original water level, the first drawdown, the radius of the pumping hole, the flow rate data of the outlet pipe, the second drawdown, and the distance between the midpoint of the upper packer and the midpoint of the lower packer. When the upper packer is located within the aquifer, the third permeability coefficient of the aquifer is iteratively calculated based on the original water level, the first drawdown, the radius of the pumping hole, the flow rate data of the outlet pipeline, the second drawdown, and the distance between the midpoint of the upper packer and the midpoint of the lower packer.

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