1. The utility model provides an indoor seepage flow analogue test device of horizontal well which characterized in that: the seepage sand tank is divided into a controllable boundary box body and a sand tank box body by a rigid partition plate along the length direction of the seepage sand tank, seepage supply small holes are uniformly arranged on the rigid partition plate, a simulated formation material is filled in the sand tank box body, a micro hole pressure sensor of the measuring device is embedded in the simulated formation material along the radial and tangential directions of the horizontal well model, simulated liquid fluid is filled in the controllable boundary box body, a liquid inlet, a plurality of overflow ports with different heights and a scale are arranged on the side wall of the controllable boundary box body, a valve is independently arranged at each overflow port, the water circulation device comprises a constant-current constant-pressure pump and a flow regulating valve, and the constant-current constant-pressure pump is communicated with the simulated formation supply liquid fluid through a pipeline and the liquid inlet of the controllable boundary box body, the horizontal well micro model comprises a test horizontal screen pipe and a hose, wherein the inlet end of the horizontal screen pipe is connected with the outlet end of the hose through a flange, a nylon pipe capable of moving freely is inserted into the horizontal screen pipe and the hose and used for simulating the position of a pump in horizontal well exploitation, the outlet end of the nylon pipe extends out of the inlet end of the hose and is connected with a diaphragm pump, a flow sensor of the measuring device is installed on the nylon pipe close to the diaphragm pump, the horizontal screen pipe is buried in a simulated formation material, the measuring device further comprises a multi-channel data acquisition terminal, and the micro hole pressure sensor and the flow sensor are in signal connection with the multi-channel data acquisition terminal.

2. The indoor seepage simulation test device of the horizontal well according to claim 1, characterized in that: the inside wall of sand groove box is from the bottom plate to the superscript scale mark.

3. The indoor seepage simulation test device of the horizontal well according to claim 1, characterized in that: and covering two layers of gauze on the side of the partition plate of the sand tank box, wherein the aperture of the gauze is about 1/2-2/3 of the median of the particle size of the simulated formation material particles.

4. The indoor seepage simulation test device of the horizontal well according to claim 1, characterized in that: the distance between the mounting hole and the bottom plate of the sand tank box body is 30-40 cm.

5. A simulation test method using the horizontal well indoor seepage simulation test device according to any one of claims 1 to 4, comprising the steps of:

A. selecting a simulated discrete particle material which is consistent with rock-soil physical and mechanical parameters such as actual horizontal well mining stratum particle size distribution curve, porosity, shale content, permeability and the like, washing and screening the simulated stratum material to remove impurities in the simulated stratum material as much as possible, fully and uniformly stirring the simulated stratum material according to a ratio for later use, filling the mixture into a sand tank box body and compacting the mixture;

B. selecting a simulated liquid fluid which is consistent with the viscosity and viscosity coefficient fluid physical property parameters of the actual horizontal well mining formation fluid for later use;

C. simulating layered filling of stratum materials: before material loading, coating silica gel on four side walls in the seepage sand tank body, then covering a simulation material for test on the silica gel, and forming a thin sand layer on the side walls so as to eliminate the influence of the side wall effect of the sand tank body on the simulation test; then, according to the scale marks arranged on the inner side of the sand tank box body, the simulated stratum materials are filled and tamped in a layered mode, so that the thickness of the simulated materials filled each time is ensured, and the simulated stratum is made as uniform as possible by adopting a layered tamping and volume weight control method in the process of filling the simulated stratum materials so as to meet the test requirements of homogeneity and isotropy; simultaneously burying micro-hole pressure sensors at different positions in the simulated material stratum along the radial and tangential directions of the horizontal well model; when the simulated stratum reaches the position of the installation round hole, the horizontal well micro model is installed, and after the installation is finished, the layered simulated stratum materials are continuously filled and tamped;

D. when the simulated formation material is filled to the position of the installation round hole, the horizontal well micro model is installed: placing a horizontal screen pipe of the horizontal well micro model into a sand tank box body simulation stratum for simulating a horizontal well exploitation section, connecting a hose and the horizontal screen pipe in a sealing manner through a flange plate through a mounting round hole in the side wall of the sand tank box body, and placing a transparent hose outside the sand tank box body for simulating a horizontal well process section; a nylon pipe with a small caliber is arranged in the transparent hose, the outlet section of the nylon pipe is connected with the diaphragm pump with an adjustable range, the pressure reduction amplitude of horizontal well exploitation is simulated through the flow of the adjusting pump, the nylon pipe can freely move in the horizontal sieve pipe and the transparent hose and is used for simulating the position of the pump in the horizontal well exploitation, and the high-precision flow sensor is installed on the nylon pipe close to the diaphragm pump and is used for measuring and acquiring the fluid extraction flow in the experiment.

E. After the horizontal well micro model is installed, the filling and tamping of stratum materials are continuously simulated, after the simulated stratum where the horizontal sieve tube is located is filled and tamped in a layered mode, a constant-pressure constant-speed constant-flow pump is used for slowly pumping a simulation fluid into the controlled boundary box body, the fluid is enabled to slowly enter the controlled boundary box body, the pumping height of the fluid is about 2-3cm lower than that of the compacted simulation material, the fluid is continuously supplied to the compacted simulation material through the rigid partition plate slowly to be saturated, meanwhile, the diaphragm pump is opened to ensure that bubbles in pores of the simulation material are discharged, so that the test effect is prevented from being influenced, meanwhile, a data acquisition instrument connected with the micro pore pressure sensor is opened to be in a working state, the stable value of the fluid head pressure in the controlled boundary box body is always kept, and the fluctuation conditions of the pressure heads of the pore pressure sensors at different positions in the micro seepage sand tank body reflected by the data acquisition instrument are continuously observed, when the stable state of the test requirement is achieved, the data acquisition instrument can display a series of different straight lines, all the pressure water head values of the micro-pore pressure sensors positioned on the same horizontal plane are equal, namely the connecting line of the pressure water head values of the micro-pore pressure sensors on the same horizontal plane is a horizontal straight line, the simulated stratum is considered to reach a saturated state at the moment, the horizontal well micro model is already positioned in an ideal and homogeneous stratum, after the simulation material is subjected to fluid saturation operation, all the bristles on the surface of the compacted simulation material are scraped, and then the compacted simulation material is continuously and uniformly poured into a lower simulation material, so that the simulation material is completely fitted before and after two times of filling, and the layering phenomenon is avoided;

F. and (4) continuously simulating the filling and weighing of the material, continuously compacting, verifying the fluid saturation, and designing the simulated stratum thickness according to the test scheme by the method.

6. The simulation test method of claim 5, wherein: the layout positions and the number of the micro pore pressure sensors are in accordance with the measurement precision required by the test design.

7. The simulation test method of claim 5, wherein: the volume weight control method of the simulation material is characterized in that the density of the test simulation material measured in a laboratory is used for controlling, the mass M of the simulation material required by filling each layer in the sand tank according to the density is calculated, the simulation material is weighed for multiple times by a platform scale, the filling of the simulation material is stopped after the weight of the simulation material poured into the sand tank reaches the calculated value, and the simulation material is tamped until the thickness reaches the requirement of a scale mark.

8. The simulation test method of claim 5, wherein: the simulated formation material can comprise one or more of river sand, quartz sand and ceramsite with different particle size specifications.

9. The simulation test method of claim 5, wherein: sludge or clay may be added to the simulation material to simulate the shale content and low permeability characteristics of the actual producing formation.

10. The simulation test method of claim 5, wherein: the simulated liquid fluid can be used for simulating horizontal well exploitation of underground water resources by using tap water and distilled water, and is used for simulating underground exploitation of saline-alkali soil strata and high-salinity salt water by adding table salt.

Background

Because the fluids such as underground oil gas, water and the like produced by the horizontal well show completely different characteristics from the vertical well in terms of seepage rules and three-dimensional pore pressure characteristics, the analytic method can only solve the relatively simple seepage problem, and the slightly complex seepage problem can only be simulated by physics or numerical values. Numerical simulation is abstracted from physical phenomena and has no intuition, so that the physical simulation is more reliable and easier to master than the numerical simulation.

In recent years, the numerical method is widely applied to the horizontal well seepage and exploitation theory and solves the problems which are difficult to solve by a plurality of analytical methods, but the physical simulation test still has the unique characteristic of solving the problems, and the seepage dynamics and the response process of underground oil gas and water in the horizontal well exploitation process are reproduced through a similar model according to a similar theory. The physical model test has the dual functions of analysis and test by using similar variables and parameters to simulate the seepage rule, and has the biggest characteristic that the seepage phenomenon and rule can be directly observed from the test; secondly, the evolution speed of seepage can be accelerated, the seepage process of several days or even dozens of years can be simulated on the model only within the time of several seconds or several minutes, and a large amount of time can be saved.

Disclosure of Invention

The invention aims to provide a horizontal well indoor seepage simulation test device and a simulation test method which are simple in structure, stable and reliable in work and capable of accurately simulating a horizontal well to exploit underground reservoir fluid.

In order to achieve the purpose, the invention adopts the following technical scheme:

a horizontal well indoor seepage simulation test device comprises a seepage sand tank, a horizontal well micro model, a measuring device and a water circulation device, wherein the seepage sand tank is a hollow cuboid without a cover in a spatial structure, the seepage sand tank is divided into a controlled boundary box body and a sand tank box body by a rigid partition plate along the length direction of the seepage sand tank, seepage supply small holes are uniformly formed in the rigid partition plate, a simulated stratum material is filled in the sand tank box body, a micro hole pressure sensor of the measuring device is embedded in the simulated stratum material along the radial direction and the tangential direction of the horizontal well model, simulated liquid fluid is filled in the controlled boundary box body, a liquid inlet, a plurality of overflow ports with different heights and a scale are formed in the side wall of the controlled boundary box body, a valve is independently installed on each overflow port, the water circulation device comprises a constant-flow constant-pressure pump and a flow regulating valve, the constant-current and constant-pressure pump is communicated with a simulated stratum to supply liquid fluid through a pipeline and a liquid inlet of the controllable boundary box body, a flow regulating valve is arranged on the pipeline, a mounting hole is arranged on the side wall of the sand tank body opposite to the rigid clapboard, the mounting hole is provided with a flange plate, the horizontal well micro model comprises a test horizontal sieve tube and a hose, the inlet end of the horizontal sieve tube is connected with the outlet end of the hose through a flange, a nylon tube which can move freely is inserted into the horizontal sieve tube and the hose for simulating the position of a pump in horizontal well exploitation, the outlet end of the nylon tube extends out through the inlet end of the hose to be connected with the diaphragm pump, the nylon tube close to the diaphragm pump is provided with the flow sensor of the measuring device, the horizontal screen pipe is embedded in a simulated formation material, the measuring device also comprises a multi-channel data acquisition terminal, the micro-hole pressure sensor and the flow sensor are in signal connection with the multi-channel data acquisition terminal.

The inside wall of sand groove box is from the bottom plate supreme scale that has pasted.

And covering two layers of gauze on the side of the partition plate of the sand tank box, wherein the aperture of the gauze is about 1/2-2/3 of the median of the particle size of the simulated formation material particles.

The distance between the mounting hole and the bottom plate of the sand tank box body is 30-40 cm.

A simulation test method using the technical scheme of the horizontal well indoor seepage simulation test device comprises the following steps:

A. selecting a simulated discrete particle material which is consistent with rock-soil physical and mechanical parameters such as actual horizontal well mining stratum particle size distribution curve, porosity, shale content, permeability and the like, washing and screening the simulated stratum material to remove impurities in the simulated stratum material as much as possible, fully and uniformly stirring the simulated stratum material according to a ratio for later use, filling the mixture into a sand tank box body and compacting the mixture;

B. selecting a simulated liquid fluid which is consistent with the viscosity and viscosity coefficient fluid physical property parameters of the actual horizontal well mining formation fluid for later use;

C. simulating layered filling of stratum materials: before material loading, coating silica gel on four side walls in the seepage sand tank body, then covering a simulation material for test on the silica gel, and forming a thin sand layer on the side walls so as to eliminate the influence of the side wall effect of the sand tank body on the simulation test; then, according to the scale marks arranged on the inner side of the sand tank box body, the simulated stratum materials are filled and tamped in a layered mode, so that the thickness of the simulated materials filled each time is ensured, and the simulated stratum is made as uniform as possible by adopting a layered tamping and volume weight control method in the process of filling the simulated stratum materials so as to meet the test requirements of homogeneity and isotropy; simultaneously burying micro-hole pressure sensors at different positions in the simulated material stratum along the radial and tangential directions of the horizontal well model; when the simulated stratum reaches the position of the installation round hole, the horizontal well micro model is installed, and after the installation is finished, the layered simulated stratum materials are continuously filled and tamped;

D. when the simulated formation material is filled to the position of the installation round hole, the horizontal well micro model is installed: placing a horizontal screen pipe of the horizontal well micro model into a sand tank box body simulation stratum for simulating a horizontal well exploitation section, connecting a hose and the horizontal screen pipe in a sealing manner through a flange plate through a mounting round hole in the side wall of the sand tank box body, and placing a transparent hose outside the sand tank box body for simulating a horizontal well process section; a nylon pipe with a small caliber is arranged in the transparent hose, the outlet section of the nylon pipe is connected with the diaphragm pump with an adjustable range, the pressure reduction amplitude of horizontal well exploitation is simulated through the flow of the adjusting pump, the nylon pipe can freely move in the horizontal sieve pipe and the transparent hose and is used for simulating the position of the pump in the horizontal well exploitation, and the high-precision flow sensor is installed on the nylon pipe close to the diaphragm pump and is used for measuring and acquiring the fluid extraction flow in the experiment.

E. After the horizontal well micro model is installed, the filling and tamping of stratum materials are continuously simulated, after the simulated stratum where the horizontal sieve tube is located is filled and tamped in a layered mode, a constant-pressure constant-speed constant-flow pump is used for slowly pumping a simulation fluid into the controlled boundary box body, the fluid is enabled to slowly enter the controlled boundary box body, the pumping height of the fluid is about 2-3cm lower than that of the compacted simulation material, the fluid is continuously supplied to the compacted simulation material through the rigid partition plate slowly to be saturated, meanwhile, the diaphragm pump is opened to ensure that bubbles in pores of the simulation material are discharged, so that the test effect is prevented from being influenced, meanwhile, a data acquisition instrument connected with the micro pore pressure sensor is opened to be in a working state, the stable value of the fluid head pressure in the controlled boundary box body is always kept, and the fluctuation conditions of the pressure heads of the pore pressure sensors at different positions in the micro seepage sand tank body reflected by the data acquisition instrument are continuously observed, when the stable state of the test requirement is achieved, the data acquisition instrument can display a series of different straight lines, all the pressure water head values of the micro-pore pressure sensors positioned on the same horizontal plane are equal, namely the connecting line of the pressure water head values of the micro-pore pressure sensors on the same horizontal plane is a horizontal straight line, the simulated stratum is considered to reach a saturated state at the moment, the horizontal well micro model is already positioned in an ideal and homogeneous stratum, after the simulation material is subjected to fluid saturation operation, all the bristles on the surface of the compacted simulation material are scraped, and then the compacted simulation material is continuously and uniformly poured into a lower simulation material, so that the simulation material is completely fitted before and after two times of filling, and the layering phenomenon is avoided;

F. and (4) continuously simulating the filling and weighing of the material, continuously compacting, verifying the fluid saturation, and designing the simulated stratum thickness according to the test scheme by the method.

The layout positions and the number of the micro pore pressure sensors are in accordance with the measurement precision required by the test design.

The volume weight control method of the simulation material is characterized in that the density of the test simulation material measured in a laboratory is used for controlling, the mass M of the simulation material required by filling each layer in the sand tank according to the density is calculated, the simulation material is weighed for multiple times by a platform scale, the filling of the simulation material is stopped after the weight of the simulation material poured into the sand tank reaches the calculated value, and the simulation material is tamped until the thickness reaches the requirement of a scale mark.

The simulated formation material can comprise one or more of river sand, quartz sand and ceramsite with different particle size specifications.

Sludge or clay may be added to the simulation material to simulate the shale content and low permeability characteristics of the actual producing formation.

The simulated liquid fluid can be used for simulating horizontal well exploitation of underground water resources by using tap water and distilled water, and is used for simulating underground exploitation of saline-alkali soil strata and high-salinity salt water by adding table salt.

The invention has the beneficial effects that: the test device and the test method can prepare and fill simulated stratums of rock-soil physical mechanical parameters such as different particle size specifications, porosity and permeability according to factors such as geological parameters, fluid characteristics and well-forming structures of the mined stratums of the horizontal well, develop a horizontal well mining seepage characteristic physical model test under conditions such as different stratum mechanical parameters, different sieve tube specifications, different horizontal section burial depths and different positions (horizontal sections and deflecting process sections) of a pump through the horizontal well indoor simulation test device, acquire and measure data through a micropore pressure and flow sensor in the test process, analyze seepage rules, three-dimensional pore pressure distribution characteristics and mining influence factors in the horizontal well mining process, and provide calculation parameters and optimized design for the actual mined stratums.

Drawings

Fig. 1 is a schematic structural diagram of a horizontal well indoor seepage simulation test device.

Fig. 2 is a schematic structural diagram of a seepage sand tank body.

Fig. 3 is a schematic view of radial (axial) layout of the micro pore pressure sensor.

FIG. 4 is a schematic diagram of the tangential (vertical) layout of micro pore pressure sensors

Detailed Description

As shown in fig. 1 to 4, the indoor horizontal well seepage simulation test device of the present invention includes a seepage sand tank, a horizontal well micro model, a measuring device and a water circulation device.

The space structure of the seepage sand tank 1 is an uncovered hollow cuboid, the seepage sand tank is divided into a controllable boundary box body 12 and a sand tank box body 13 by a rigid partition plate 11 along the length direction of the seepage sand tank, seepage supply small holes are uniformly arranged on the rigid partition plate 11, in order to prevent a simulated formation material from entering the controllable boundary box body through the partition plate, two layers of gauze covers the partition plate side of the sand tank box body, and the aperture of the gauze is about 1/2-2/3 of the median of the particle size of the simulated formation material; the clapboard has a one-way infiltration function between the controlled boundary box body and the sand tank box body, and only the water flow in the controlled boundary box body slowly infiltrates into the simulated stratum soil 14 of the sand tank box body, but the simulated stratum soil of the sand tank box body is prevented from entering the controlled boundary box body; through the accurate control and adjustment of the infiltration water quantity of the partition plate, the position change of the constant head in the controllable boundary box body is smaller, the replenishment relation of the actual stratum is simulated more truly, and the test data is more real and accurate; the length, width and height of the sand tank body and the controllable boundary box body meet the geometric similarity requirement of a similar theory of a physical model test, in the embodiment, the length is about 5 meters, the width is about 2.5 meters, and the height is about 1.5 meters, the rigid partition board is 400mm away from the controllable boundary box body, the inner side of the sand tank box body is marked with a scale mark (the minimum scale unit cm) from the bottom plate to the top of the box body, the bottom plate boundary and the side plate boundary can be regarded as an isolation boundary, and the sand tank box body 13 is filled with simulated formation materials of rock-soil physical-mechanical parameters such as different particle size specifications, porosity, permeability and the like, which are prepared according to a test scheme; a water inlet 121 is formed in one side wall of the controllable boundary box body, a plurality of overflow ports 122 with different heights and a pasting graduated scale are formed in the other opposite side wall of the controllable boundary box body and are used for storing and maintaining simulated liquid fluid for a test with a certain water head height (namely the pumping height of the fluid is about 2-3cm lower than that of a simulated material compacted every time), continuous and stable supply is continuously carried out on a simulated stratum in the sand tank box body through a rigid partition plate, and a hole 131 with the diameter of 90mm is formed in the side wall of the sand tank box body, opposite to the rigid partition plate, in the axial direction with the height of 30-40cm from the bottom of the sand tank box body and is used for installing and connecting a horizontal well micro model.

The measuring device comprises a micro pore pressure sensor, a flow sensor and the multi-channel data acquisition terminal 2, wherein the micro pore pressure sensor and the flow sensor are in signal connection with the multi-channel data acquisition terminal. As shown in fig. 3 and 4, the micro-pore pressure sensors 20 of the measuring device are embedded in the simulated formation material along the radial and tangential directions of the horizontal well model, and are used for acquiring and measuring the pore pressures of the horizontal well radial and tangential monitoring points in the physical simulation test process, analyzing the three-dimensional pore pressure distribution characteristics of the formation around the horizontal well in the horizontal well mining process, and the arrangement positions and the number of the micro-pore pressure sensors are in accordance with the measurement precision required by the test design.

The horizontal well micro model mainly comprises a horizontal sieve tube 21 (which can be a plastic tube, a stainless steel tube or an industrial sieve tube) and a transparent hose 22, wherein a flange is arranged on the installation round hole, the inlet end of the horizontal sieve tube is in sealed butt joint with one end of the flange, the other end of the flange is connected with one end of a switch valve, the other end of the switch valve is connected with the outlet end of the hose, the horizontal sieve tube close to the hose is arranged in a simulated stratum of a sand tank box body and used for simulating a mining section of a horizontal well, and the transparent hose is arranged outside a seepage sand tank and used for simulating a process section of the horizontal well; the transparent hose is internally provided with a nylon pipe 23 with a smaller diameter, the high-precision flow sensor is arranged on the nylon pipe close to the diaphragm pump and used for measuring and collecting the fluid extraction flow in the test, the nylon pipe 23 can freely move in the horizontal sieve pipe and the transparent hose and used for simulating the position of the pump in the exploitation of the horizontal well, the outlet section of the nylon pipe is connected with the diaphragm pump with adjustable range, the pressure reduction amplitude of the exploitation of the horizontal well is simulated by adjusting the flow of the pump, and the purposes of matching seepage speed and exploitation speed and optimizing the exploitation are achieved.

The water circulation device comprises a constant-current and constant-pressure pump 41, a flow regulating valve and a water inlet flow retarder, wherein the constant-current and constant-pressure pump is communicated with a liquid inlet of the control boundary box body through a pipeline and supplies liquid fluid to a simulated stratum; the water head pressure of the horizontal well seepage test is controlled by adjusting the working pressure of the constant-pressure constant-speed advection pump, and the pressure difference of horizontal well exploitation is simulated.

The sand tank box body and the controllable boundary box body can be made of organic glass, steel plates and the like (the thickness meets the strength required by test requirements), and the sand tank box body and the controllable boundary box body have certain rigidity, so that the influence of elastic release energy on test data caused by box body deformation in the test process is avoided.

The simulation experiment method comprises the following specific steps:

A. selecting a simulated discrete particle material which is consistent with rock-soil physical and mechanical parameters such as actual horizontal well mining stratum particle size distribution curve, porosity, argillaceous content and permeability, washing and screening the simulated stratum material to remove impurities in the simulated stratum material as much as possible, and fully and uniformly stirring the simulated discrete particle material according to a certain proportion (adjusting parameters such as permeability, porosity and argillaceous content) for later use; as shown in fig. 2.

B. Selecting a simulated liquid fluid which is consistent with the viscosity and viscosity coefficient fluid physical property parameters of the actual horizontal well exploitation formation fluid for later use,

C. simulating layered filling and tamping of stratum materials and verifying fluid saturation: before material loading, coating silica gel on four side walls in the seepage sand tank body, then covering a simulation material for test on the silica gel, and forming a thin sand layer on the side walls so as to eliminate the influence of the side wall effect of the seepage sand tank body on the simulation test; then, filling and tamping the simulated stratum materials according to the scale marks arranged on the inner side of the sand tank body so as to ensure the thickness of the simulated materials filled each time; in the step of filling the simulation material, embedding depth micro-hole pressure sensors for collecting and analyzing three-dimensional hole pressure distribution characteristics of the stratum around the horizontal well in the exploitation process of the horizontal well along the radial direction and the tangential direction of the horizontal well model at different positions (reflecting the hole pressure fluctuation condition of underground fluid in the whole simulation stratum as much as possible, and the arrangement position and the number are according to the measurement precision required by the experimental design) in the seepage sand groove simulation material according to the test scheme; in the filling process of the simulated stratum material, a method of layering tamping and volume weight control is adopted to ensure that the simulated stratum is as uniform as possible so as to meet the test requirements of homogeneity and isotropy; the volume weight control method of the simulation material is characterized in that the density of the test simulation material measured by a laboratory is used for controlling, the mass M of the simulation material required by filling each layer (100mm) in a sand tank according to the density is calculated, the simulation material is weighed for multiple times by a platform scale, the filling of the simulation material is stopped after the weight of the simulation material poured into the sand tank reaches the calculated value, and the simulation material is tamped to the thickness (such as 100mm) required by a scale mark;

D. when the simulated formation material is filled to the position of the installation round hole, the horizontal well micro model is installed: placing a horizontal screen pipe of the horizontal well micro model into a sand tank box body simulation stratum for simulating a horizontal well exploitation section, connecting a hose and the horizontal screen pipe in a sealing manner through a flange plate through a mounting round hole in the side wall of the sand tank box body, and placing a transparent hose outside the sand tank box body for simulating a horizontal well process section; a nylon pipe with a smaller diameter is arranged in the transparent hose, the outlet section of the nylon pipe is connected with the adjustable range diaphragm pump, the pressure reduction amplitude of horizontal well exploitation is simulated by adjusting the flow of the pump, namely the liquid level height in the transparent hose outside the sand tank box body is controlled by adjusting the flow of the pump, and different water level difference values between the outside of the sand tank and a controllable boundary are formed to generate hydraulic gradient; the nylon pipe can freely move in the horizontal sieve pipe and the transparent hose and is used for simulating the position of a pump in horizontal well exploitation, and the high-precision flow sensor is arranged on the nylon pipe close to the diaphragm pump and is used for measuring and collecting the fluid extraction flow in a test.

E. After the horizontal well micro model is installed, the filling and tamping of stratum materials are continuously simulated, after the simulated stratum where the horizontal sieve tube is located is filled and tamped in a layered mode, a constant-pressure constant-speed constant-flow pump is used for slowly pumping a simulation fluid into the controlled boundary box body, the fluid is enabled to slowly enter the controlled boundary box body, the pumping height of the fluid is about 2-3cm lower than that of the compacted simulation material, the fluid is continuously supplied to the compacted simulation material through the rigid partition plate slowly to be saturated, meanwhile, the diaphragm pump is opened to ensure that bubbles in pores of the simulation material are discharged, so that the test effect is prevented from being influenced, meanwhile, a data acquisition instrument connected with the micro pore pressure sensor is opened to be in a working state, the stable value of the fluid head pressure in the controlled boundary box body is always kept, and the fluctuation conditions of the pressure heads of the pore pressure sensors at different positions in the micro seepage sand tank body reflected by the data acquisition instrument are continuously observed, when the stable state of the test requirement is achieved, the data acquisition instrument can display a series of different straight lines, all the pressure water head values of the micro-pore pressure sensors positioned on the same horizontal plane are equal, namely the connecting line of the pressure water head values of the micro-pore pressure sensors on the same horizontal plane is a horizontal straight line, the simulated stratum is considered to reach a saturated state at the moment, the horizontal well micro model is already positioned in an ideal and homogeneous stratum, after the simulation material is subjected to fluid saturation operation, all the bristles on the surface of the compacted simulation material are scraped, and then the compacted simulation material is continuously and uniformly poured into a lower simulation material, so that the simulation material is completely fitted before and after two times of filling, and the layering phenomenon is avoided;

F. and (4) continuously simulating the filling and weighing of the material, continuously compacting, verifying the fluid saturation, and designing the simulated stratum thickness according to the test scheme by the method.

The simulated formation material is a bulk particle accumulation body meeting a certain particle size distribution rule, and the accumulation body is of a pore structure.

The simulated formation material can comprise one or more of river sand, quartz sand and ceramsite with different particle size specifications; sludge or clay may be added to the simulation material in a proportion to simulate the actual production formation's mudcontent and low permeability characteristics.

The simulated liquid fluid can simulate the horizontal well exploitation of underground water resources by using tap water and distilled water, and is used for simulating the underground exploitation of saline-alkali soil strata and high-salinity salt water by adding salt; simulating the exploitation of underground petroleum by using industrial waste oil; the mixing of water and industrial waste oil in a certain proportion simulates the pumping drainage pollution remediation of the soil in-situ horizontal well of organic hydrocarbons.

The layout number and position of the micro pore pressure sensors and the number of channels of the data acquisition instrument can be changed according to the measurement precision required by the test design. The micro pore pressure sensor has the characteristics of high precision (0.1% FS), small volume (2.5mm x 3.5mm) and high stability; the data acquisition instrument is 16 channels or 32 channels. The arrangement and installation of the micro pore pressure and flow sensors are used for acquiring the seepage field and pore pressure fluctuation conditions of formation fluid around the horizontal well in the exploitation process of the horizontal well.

The permeability of the partition between the seepage sand tank box body and the controllable boundary box body can be adjusted through the porosity of the sand net covered on the partition, so that the permeability can be used for simulating the replenishment characteristics (strong, medium and weak) of the actual stratum, and the porosity is designed and calculated according to the permeability coefficient of the stratum to be simulated.

The test device and the test method can prepare and fill simulated stratums of rock-soil physical mechanical parameters such as different particle size specifications, porosity and permeability according to factors such as geological parameters, fluid characteristics and well-forming structures of the mined stratums of the horizontal well, develop a horizontal well mining seepage characteristic physical model test under conditions such as different stratum mechanical parameters, different sieve tube specifications, different horizontal section burial depths and different positions (horizontal sections and deflecting process sections) of a pump through an indoor simulation test of the horizontal well, acquire and measure data through a micropore pressure and flow sensor in the test process, analyze seepage rules, three-dimensional pore pressure distribution characteristics and mining influence factors in the horizontal well mining process, and provide calculation parameters and optimized design for the actual mined stratums.