A visualization experimental device for flow transport in a temporarily plugged fracturing tube considering the stress shadowing effect of multi-cluster perforations.

Abstract

This invention discloses a visualization experimental device for the flow migration in fractured tubing with temporary plugging, considering the stress shadow effect of multi-cluster perforations. Belonging to the field of oil and gas reservoir enhancement technology, it includes: a spiral mixing unit for temporary plugging materials; a perforation cluster orifice adjustment unit connected to the output end of the spiral mixing unit for visual observation of the plugging agent migration; a perforation cluster pressure control unit connected to the orifice adjustment unit to simulate the stress shadow effect caused by inter-fracture interference during multi-fracture competitive propagation; a perforation cluster flow detection unit connected to the orifice adjustment unit for detecting flow changes in each perforation cluster branch; a wellbore tilt hydraulic unit for changing the wellbore tilt angle; and a recovery unit for recovering fracturing fluid. This invention enables full-process monitoring of the migration and flow competition distribution of the plugging agent under different perforation numbers, diameters, density, perforation methods, and wellbore tilt angles, providing guidance for the formulation of temporary plugging fracturing schemes.

Description

Technical Field

[0001] This invention belongs to the field of oil and gas reservoir production enhancement and stimulation technology, and more specifically, it relates to a visualization experimental device for flow migration in fractured pipes that considers the stress shadowing effect of multi-cluster perforation. Background Technology

[0002] As oil and gas exploration and development advances to deeper and ultra-deep formations, reservoir geological conditions are becoming increasingly complex. During volumetric fracturing, the stress shadowing effect caused by inter-fracture interference during the propagation of multiple clusters of perforated fractures often leads the fracturing fluid to preferentially enter the perforations with the least resistance or the dominant primary fractures that have already been opened. This results in the overgrowth of dominant fractures, while other areas cannot be effectively stimulated, making it difficult to achieve balanced propagation of multiple clusters of fractures and ultimately affecting the overall reservoir recovery rate. By pumping in temporary plugging agents (such as particles, fibers, temporary plugging balls, or combinations thereof) to seal some perforations, changes in flow distribution are induced, improving the uniformity of fracture propagation. Currently, most temporary plugging process designs rely on experience or simplified theoretical calculations and have not yet considered the stress shadowing effect of competitive propagation of multiple clusters of fractures, which plays a crucial role in flow competition and distribution.

[0003] In order to overcome the limitations of current technology, there is an urgent need for an experimental device that can measure the effects of different carrier fluid viscosities, pumping speeds, types of temporary plugging agents, and concentrations of temporary plugging agents on the migration and plugging efficiency of the temporary plugging agent. Summary of the Invention

[0004] This invention aims to provide accurate data for the control mechanism of competitive propagation and synergistic temporary plugging in deep reservoirs, and to conduct experiments on the effects of different carrier fluid viscosities, pumping rates, plugging agent types, and plugging agent concentrations on plugging agent migration and plugging efficiency. To achieve the above objectives, this invention adopts the following technical solution: A visualization experimental device for flow transport in a temporarily plugged fracturing tube considering the stress shadowing effect of multiple perforations includes: The temporary plugging material spiral mixing unit is used for mixing and transporting temporary plugging agents and fracturing fluids; The perforation cluster orifice adjustment unit is connected to the output end of the temporary plugging material spiral mixing unit to simulate the changes in the wellbore and the perforation cluster orifice on the wellbore, and to perform visual observation of the migration of the temporary plugging agent. A perforation cluster pressure control unit, connected to the perforation cluster orifice adjustment unit, is used to adjust the pressure of the perforation cluster of the perforation cluster in the perforation cluster orifice adjustment unit to simulate the stress shadowing effect caused by inter-crack interference during multi-crack competitive propagation in fracturing. A perforation cluster flow detection unit, connected to the perforation cluster orifice adjustment unit, is used to detect the flow changes of each perforation cluster branch of the perforation cluster orifice adjustment unit; A well inclination lifting hydraulic unit is provided correspondingly to the perforation cluster orifice adjustment unit and is used to change the well inclination angle of the perforation cluster orifice adjustment unit; A recovery unit, which is connected to the perforation cluster orifice adjustment unit, is used to recover fracturing fluid.

[0005] Furthermore, the temporary plugging material spiral mixing unit includes: Inject into a storage tank to store fracturing fluid; A double-acting variable flow vane pump, wherein the inlet of the double-acting variable flow vane pump is connected to the liquid storage tank via an injection hose; A dynamic spiral solid-liquid two-phase mixer is provided, wherein the inlet of the dynamic spiral solid-liquid two-phase mixer is connected to the outlet of the double-acting variable flow vane pump, and the double-acting variable flow vane pump pumps fracturing fluid into the dynamic spiral solid-liquid two-phase mixer; the dynamic spiral solid-liquid two-phase mixer has a temporary plugging agent inlet, and the dynamic spiral solid-liquid two-phase mixer mixes the temporary plugging agent and fracturing fluid and then delivers them to the perforation cluster orifice adjustment unit.

[0006] Furthermore, the dynamic helical solid-liquid two-phase mixer includes: Mixer housing; Spiral mixer blades, which are rotatably mounted inside the mixer housing via deep groove ball bearings; The motor housing has the same diameter as the spiral mixer blades. Inside the motor housing is a drive motor, a small gear connected to the drive motor via a key, and a large gear meshing with the small gear. The large gear is connected to the drive shaft of the spiral mixer blades via a key. The mixer housing is provided with a gradually expanding member at the end away from the motor housing, and the large-diameter end of the gradually expanding member is connected to the perforation cluster eye adjustment unit.

[0007] Furthermore, the perforation cluster eye adjustment unit includes: A transparent well casing, wherein the first end of the transparent well casing is connected to the large-diameter end of the expanding member, and the second end is a closed end; Multiple perforation cluster modules are spaced apart on the transparent wellbore. Each perforation cluster module has a ring-shaped hollow structure, and its inner wall has multiple distributed holes that communicate with the cavity of the transparent wellbore. The number, diameter, density, and perforation method of the holes are all adjustable. An opening is formed on the outer wall of each perforation cluster module. A conical flow guide cap is provided, with its large-diameter end rooted on an opening in the outer wall of the perforation cluster module, and its small-diameter end connected to the first end of the tubing. The second end of the tubing is connected to the recovery unit. The perforation cluster flow detection unit and the perforation cluster orifice adjustment unit are both installed on the tubing.

[0008] Furthermore, the perforation cluster flow detection unit includes multiple flow meters, each of which is configured in a one-to-one correspondence with a perforation cluster module, and the flow meters are installed on the tubing column.

[0009] Furthermore, the perforation cluster orifice adjustment unit includes multiple electrically controlled back pressure valves and manual valves, with each of the multiple electrically controlled back pressure valves and manual valves corresponding to one of the multiple perforation cluster modules, and the electrically controlled back pressure valves are installed on the tubing column.

[0010] Furthermore, the recycling unit includes: A manifold, one end of which is open and the other end is closed; the manifold is connected to the second end of multiple manifolds; A recycling hose, the first end of which is connected to the open end of the manifold; A recycling storage tank is provided, and the second end of the recycling hose is connected to the recycling storage tank.

[0011] Furthermore, the well tilting and lifting hydraulic unit includes: Base support frame; The transparent wellbore and the double-acting variable flow vane pump are fixedly installed on the upper support frame of the base; the first end of the upper support frame of the base is connected to the first end of the lower support frame of the base by a pin. A hydraulic assembly, wherein the fixed end of the hydraulic assembly is hinged to a non-end position of the lower support frame of the base, and the driving end of the hydraulic assembly is hinged to a non-end position of the upper support frame of the base, and the hydraulic assembly is used to change the included angle between the upper support frame of the base and the lower support frame of the base.

[0012] Compared with the prior art, the present invention has the following beneficial effects: This invention provides a visualization experimental device for the flow migration of temporary plugging fracturing tubing that considers the stress shadowing effect of multi-cluster perforation. It can realize the full-process monitoring of the migration and flow competition distribution of the temporary plugging agent under different perforation numbers, diameters, density, perforation methods, and well inclination angles, and has guiding significance for the formulation of temporary plugging fracturing schemes. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0014] Figure 1 A schematic diagram of the overall structure of a visualization experimental device for flow transport in a fractured tube with temporary plugging at the perforation site, taking into account the stress shadowing effect of multiple perforations. Figure 2 This is a schematic diagram of the perforation cluster eye adjustment unit; Figure 3 A schematic diagram showing the structural setup of the perforation cluster apertures; Figure 4 A schematic diagram of the structure of the spiral mixing unit for temporary plugging materials; Figure 5 This is a schematic diagram of the hydraulic unit for lifting and lowering the shaft. Figure 6 This is an experimental setup for visualizing the flow migration of a fractured pipe with temporary plugging at the fracture opening, taking into account the stress shadowing effect of multiple perforations, under different well inclination angles (angle 1). Figure 7 This is an experimental setup for visualizing the flow migration of a fractured pipe with temporary plugging at the perforation site, considering the stress shadowing effect of multiple perforations, under different well inclination angles (angle two).

[0015] The components include: 1. Injection storage tank; 2. Computer; 3. Hoisting clamp; 4. Injection hose; 5. Double-acting variable flow vane pump; 6. Spiral mixer blades; 7. Lower support frame; 8. Upper support frame; 9. Trumpet mouth; 10. Well inclination lifting hydraulic unit; 11. Transparent wellbore; 12. High-speed camera; 13. Conical guide cap; 14. Electrically controlled back pressure valve; 15. Flow meter; 16. Pin shaft; 17. Recovery storage tank; 18. Recovery hose; 19. 20. Back pressure overflow control valve; 21. Manual valve; 22. Manifold; 23. Feed cover; 24. Temporary plugging agent inlet; 25. Temporary plugging agent filter screen; 26. Perforation module; 27. Hole; 28. Pinion; 29. ​​Bolt; 30. Nut; 31. Deep groove ball bearing; 32. Spiral mixer blade; 33. Flat key; 34. Waterproof motor; 35. Large gear; 36. Hydraulic cylinder base; 37. Hydraulic cylinder; 38. Hydraulic rod; 39. Cotter pin. Detailed Implementation

[0016] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. 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.

[0017] Example 1

[0018] refer to Figures 1-7 A visualization experimental device for flow transport in a temporarily plugged fracturing tube considering the stress shadowing effect of multiple perforations, comprising: The temporary plugging material spiral mixing unit is used for mixing and transporting temporary plugging agents and fracturing fluids; The perforation cluster orifice adjustment unit is connected to the output end of the temporary plugging material spiral mixing unit to simulate the changes in the perforation cluster orifice on the wellbore and to perform visual observation of the migration of the temporary plugging agent. The perforation cluster pressure control unit is connected to the perforation cluster orifice adjustment unit and is used to adjust the pressure of the perforation cluster in the perforation cluster orifice adjustment unit to simulate the stress shadowing effect caused by inter-crack interference during multi-crack competitive propagation in fracturing. The perforation cluster flow detection unit is connected to the perforation cluster orifice adjustment unit and is used to detect the flow changes of each perforation cluster branch of the perforation cluster orifice adjustment unit. The well inclination lifting hydraulic unit 10 is set in correspondence with the perforation cluster orifice adjustment unit and is used to change the well inclination angle of the perforation cluster orifice adjustment unit. The recovery unit is connected to the perforation cluster orifice adjustment unit and is used to recover fracturing fluid.

[0019] In this embodiment, the temporary plugging material spiral mixing unit includes: Inject into storage tank 1 to store fracturing fluid; The inlet of the double-acting variable flow vane pump 5 is connected to the storage tank via an injection hose 4; the injection hose 4 is connected to the outlet of the storage tank via a clamp 3. The dynamic spiral solid-liquid mixer has its inlet connected to the outlet of a double-acting variable flow vane pump 5, which pumps fracturing fluid into the dynamic spiral solid-liquid mixer. The dynamic spiral solid-liquid mixer has a temporary plugging agent inlet 23, which mixes the temporary plugging agent and fracturing fluid and then delivers them to the perforation cluster orifice adjustment unit.

[0020] In this embodiment, the dynamic helical solid-liquid two-phase mixer includes: Mixer housing; The spiral mixer blades 6 are rotatably mounted inside the mixer housing via deep groove ball bearings; The motor housing is set with the same diameter as the spiral mixer blades 6. Inside the motor housing is a drive motor, a small gear 27 connected to the drive motor via a key 32, and a large gear 34 meshing with the small gear 27. The large gear 34 is connected to the drive shaft of the spiral mixer blades 6 via a key 32. A diffuser is provided at the end of the mixer housing away from the motor housing, and the large-diameter end of the diffuser is connected to the perforation cluster orifice adjustment unit.

[0021] Specifically, the dynamic spiral solid-liquid two-phase mixer is connected to the double-acting variable flow vane pump 5 and the bell mouth 9. The temporary plugging agent is added from the inlet of the dynamic spiral solid-liquid two-phase mixer. After tightening, the internal waterproof motor 33 transmits power to the spiral mixer blades 6 through gear transmission and key connection. The two ends of the spiral mixer blades 6 are equipped with deep groove ball bearings to reduce rotational friction.

[0022] In this embodiment, the perforation cluster aperture adjustment unit includes: Transparent well shaft 11, the first end of which is connected to the large-diameter end of the expanding member, and the second end is a closed end; Multiple perforation cluster modules are spaced apart on the transparent well tube 11. Each perforation cluster module has a ring-shaped hollow structure, and multiple distributed holes 26 are opened on the inner wall of the perforation cluster module. The holes 26 are connected to the cavity of the transparent well tube 11. The number, diameter, density and perforation method of the holes 26 are adjustable. An opening is opened on the outer wall of the perforation cluster module. The conical flow guide cap 13 has its large-diameter end root installed on the opening on the outer wall of the perforation cluster module, and its small-diameter end connected to the first end of the tubing. The second end of the tubing is connected to the recovery unit. The perforation cluster flow detection unit and the perforation cluster orifice adjustment unit are both installed on the tubing.

[0023] The transparent well casing 11 is made of polymethyl methacrylate and has external threads. The perforation cluster module is threaded and installed on the transparent well casing 11. The tapered flow guide cap 13 has threads at its root that fit with the openings on the outer wall of the perforation cluster module.

[0024] Specifically, there are 3 perforation cluster modules. The temporary plugging agent is added from the inlet of the dynamic spiral solid-liquid two-phase mixer and then pumped into the transparent wellbore 11 by the large-displacement double-acting variable flow vane pump 5 after tightening.

[0025] In this embodiment, the expanding part is preferably a bell mouth 9, which connects the dynamic spiral solid-liquid two-phase mixer and the transparent well barrel 11. The bell mouth 9 and the transparent well barrel 11 are connected by bolts 28, nuts 29 and flanges. The function of the bell mouth 9 is to enlarge the small diameter of the dynamic spiral solid-liquid two-phase mixer to the large diameter of the transparent well barrel 11.

[0026] In this embodiment, the perforation cluster flow detection unit includes multiple flow meters 15, which are configured one-to-one with multiple perforation cluster modules, and the flow meters 15 are installed on the tubing column.

[0027] The perforation cluster orifice adjustment unit includes multiple electrically controlled back pressure valves 14 and manual valves 20. The multiple electrically controlled back pressure valves 14 and multiple manual valves 20 are set one-to-one with the multiple perforation cluster modules. The electrically controlled back pressure valves 14 are installed on the tubing string.

[0028] Specifically, each pressure control unit and flow detection unit is mounted on the same steel tubing string. The lower end of the tubing string is threaded to the narrower side of the tapered flow guide cap 13. The pressure control unit mainly consists of three sets of parallel electrically controlled back pressure valves 14 (relief valves), which provide different hydraulic pressure values ​​to the three tubing strings to simulate the stress shadow effect caused by inter-crack interference during the competitive propagation of multiple fractures in fracturing. The flow detection unit mainly consists of three sets of parallel flow meters 15 to detect the flow changes in each perforation cluster branch. The flow detection device is located below the pressure control unit. A manual valve 20 is installed above the tubing string to control the fluid flow to one branch and test the temporary plugging strength.

[0029] In this embodiment, the recycling unit includes: Manifold 21, one end of which is open and the other end is closed; manifold 21 is connected to the second end of multiple manifolds; The first end of the recovery hose 18 is connected to the open end of the manifold 21; The second end of the recovery hose 18 is connected to the recovery storage tank 17.

[0030] In this embodiment, the well tilting and lifting hydraulic unit 10 includes: 7. Base support frame; The upper support frame 8, the transparent well shaft 11, and the double-acting variable flow vane pump 5 are fixedly installed on the upper support frame 8; the first end of the upper support frame 8 is connected to the first end of the lower support frame 7 via a pin 16. The hydraulic component has a fixed end that is hinged to the non-end position of the lower support frame 7 of the base, and a drive end that is hinged to the non-end position of the upper support frame 8 of the base. The hydraulic component is used to change the included angle between the upper support frame 8 of the base and the lower support frame 7 of the base.

[0031] Specifically, the hydraulic assembly connects the upper support frame 8 and the lower support frame 7 of the base via a pin 16, and the connection is axially positioned via a cotter pin 38. The function of the well tilting and lifting hydraulic unit 10 is to set different angles (10°~45°) of the base under the transparent well casing 11.

[0032] The hydraulic components include a hydraulic cylinder base 35 and a hydraulic cylinder 36. The hydraulic cylinder base 35 is hinged to the lower support frame 7 of the base via a pin 16. The hydraulic cylinder 36 is installed inside the hydraulic cylinder base 35. The hydraulic rod 37 of the hydraulic cylinder 36 is hinged to the upper support frame 8 of the base via a pin 16.

[0033] This embodiment provides a visualization experimental device for the flow migration of fractured tubing temporarily plugged with multi-cluster perforation stress shadow effect. It also includes a control module and a high-speed camera 12. The high-speed camera 12 is set up in correspondence with the transparent wellbore 11 and the perforation module to collect the changes in the plugging image of the perforation 26 in real time.

[0034] The control module is a control system set in computer 2. The control system is electrically connected to double-acting variable flow vane pump 5, high-speed camera 12, back pressure overflow control valve 19, waterproof motor 33, electrically controlled back pressure valve 14, and flow meter 15.

[0035] Example 2

[0036] This embodiment is based on Example 1, and uses the testing of the migration law of the temporary plugging agent under different experimental conditions as an example for illustration.

[0037] A visualization experimental device for flow migration in a fractured pipe with temporary plugging considering the stress shadowing effect of multiple perforations includes a temporary plugging material spiral mixing unit, a perforation cluster orifice adjustment unit, a perforation cluster pressure control unit, a perforation cluster flow detection unit, and a well deviation lifting hydraulic unit 10.

[0038] Temporary plugging material spiral mixing unit ( Figure 3 The device consists of a deep groove ball bearing (6201), a large gear 34, a small gear 27, a flat key 32, a spiral mixer blade 6, and a waterproof motor 33. The spiral mixer blade 6 is spiral-shaped and runs through the entire mixing device. The deep groove ball bearing (6201) and the waterproof motor 33 are matched with the support on the inner wall of the tubing column by interference fit. The feeding cover 22 and the temporary plugging agent inlet 23 are connected by threaded connection to achieve closure during pressurization.

[0039] During the temporary sealing experiment, different perforation modules 25 (reference) were installed. Figure 2 To achieve experimental conditions with different numbers of holes, hole density, hole diameter, and hole arrangement, the hydraulic rod 37 in the hydraulic cylinder 36 extends to push the support frame 8 on the base to rise, so as to meet the requirements of different experimental well inclination angles.

[0040] Open all manual valves 20, adjust back pressure overflow control valve 19, and simulate the stress shadow effect generated by the competitive propagation of multiple cluster cracks by adjusting different pressure values. Put the temporary plugging ball into the temporary plugging agent inlet 23 and tighten the feeding cover 22. Add water to the storage tank 1 to more than 80%. At the same time, power on the waterproof motor 33 and the double-acting variable flow vane pump 5. Adjust the liquid flow rate as needed. The waterproof motor 33 drives the vane to mix solid and liquid through gear transmission.

[0041] The temporary plugging agent is adsorbed in the temporary plugging agent filter screen 24 under the action of fluid inertial force and drag force, affecting the flow distribution and flow state. The flow change pattern of each perforation cluster can be measured by the flow meter 15.

[0042] Example 3

[0043] This embodiment is based on Embodiment 1, and uses the testing of the plugging performance of the temporary plugging agent as an example for illustration.

[0044] When conducting a temporary plugging agent strength test, with manual valve 20 closing part of the branch and leaving only one branch open, the fluid carries the temporary plugging agent to the joint for the temporary plugging agent sealing strength test. By continuously increasing the injection pressure, the ultimate pressure value that the temporary plugging ball can be measured.

[0045] The technical solutions of the present invention have been fully described above. It should be noted that the specific embodiments of the present invention are not limited to the above description. All technical solutions formed by those skilled in the art based on the spirit and essence of the present invention by adopting equivalent transformations or equivalent transformations in terms of structure, method or function fall within the protection scope of the present invention.

Claims

1. A visualized experimental device for perforation temporary plugging and fracturing pipe flow migration considering multi-cluster perforation stress shadow effect, characterized in that, include: The temporary plugging material spiral mixing unit is used for mixing and transporting temporary plugging agents and fracturing fluids; The perforation cluster orifice adjustment unit is connected to the output end of the temporary plugging material spiral mixing unit to simulate the changes in the wellbore and the perforation cluster orifice on the wellbore, and to perform visual observation of the migration of the temporary plugging agent. A perforation cluster pressure control unit, connected to the perforation cluster orifice adjustment unit, is used to adjust the pressure of the perforation cluster of the perforation cluster in the perforation cluster orifice adjustment unit to simulate the stress shadowing effect caused by inter-crack interference during multi-crack competitive propagation in fracturing. A perforation cluster flow detection unit, connected to the perforation cluster orifice adjustment unit, is used to detect the flow changes of each perforation cluster branch of the perforation cluster orifice adjustment unit; A well inclination lifting hydraulic unit is provided correspondingly to the perforation cluster orifice adjustment unit and is used to change the well inclination angle of the perforation cluster orifice adjustment unit; A recovery unit, which is connected to the perforation cluster orifice adjustment unit, is used to recover fracturing fluid.

2. The visualization experimental device for flow transport in a temporarily plugged fracturing tube considering the stress shadowing effect of multiple perforations as described in claim 1, characterized in that, The temporary plugging material spiral mixing unit includes: Inject into a storage tank to store fracturing fluid; A double-acting variable flow vane pump, wherein the inlet of the double-acting variable flow vane pump is connected to the liquid storage tank via an injection hose; A dynamic spiral solid-liquid two-phase mixer is provided, wherein the inlet of the dynamic spiral solid-liquid two-phase mixer is connected to the outlet of the double-acting variable flow vane pump, and the double-acting variable flow vane pump pumps fracturing fluid into the dynamic spiral solid-liquid two-phase mixer; the dynamic spiral solid-liquid two-phase mixer has a temporary plugging agent inlet, and the dynamic spiral solid-liquid two-phase mixer mixes the temporary plugging agent and fracturing fluid and then delivers them to the perforation cluster orifice adjustment unit.

3. The visualization experimental device for flow transport in a temporarily plugged fracturing tube considering the stress shadowing effect of multiple perforations as described in claim 2, characterized in that, The dynamic spiral solid-liquid two-phase mixer includes: Mixer housing; Spiral mixer blades, which are rotatably mounted inside the mixer housing via deep groove ball bearings; The motor housing has the same diameter as the spiral mixer blades. Inside the motor housing is a drive motor, a small gear connected to the drive motor via a key, and a large gear meshing with the small gear. The large gear is connected to the drive shaft of the spiral mixer blades via a key. The mixer housing is provided with a gradually expanding member at the end away from the motor housing, and the large-diameter end of the gradually expanding member is connected to the perforation cluster eye adjustment unit.

4. The visualization experimental device for flow transport in a temporarily plugged fracturing tube considering the stress shadowing effect of multiple perforations as described in claim 3, characterized in that, The perforation cluster eyelet adjustment unit includes: A transparent well casing, wherein the first end of the transparent well casing is connected to the large-diameter end of the expanding member, and the second end is a closed end; Multiple perforation cluster modules are spaced apart on the transparent wellbore. Each perforation cluster module has a ring-shaped hollow structure, and its inner wall has multiple distributed holes that communicate with the cavity of the transparent wellbore. The number, diameter, density, and perforation method of the holes are all adjustable. An opening is formed on the outer wall of each perforation cluster module. A conical flow guide cap is provided, with its large-diameter end rooted on an opening in the outer wall of the perforation cluster module, and its small-diameter end connected to the first end of the tubing. The second end of the tubing is connected to the recovery unit. The perforation cluster flow detection unit and the perforation cluster orifice adjustment unit are both installed on the tubing.

5. The visualization experimental device for flow transport in a temporarily plugged fracturing tube considering the stress shadowing effect of multiple perforations as described in claim 4, characterized in that, The perforation cluster flow detection unit includes multiple flow meters, each flow meter being configured in a one-to-one correspondence with a perforation cluster module, and the flow meters being installed on the tubing column.

6. The visualization experimental device for flow transport in a temporarily plugged fracturing tube considering the stress shadowing effect of multiple perforations as described in claim 5, characterized in that, The perforation cluster orifice adjustment unit includes multiple electrically controlled back pressure valves and manual valves. The multiple electrically controlled back pressure valves and the multiple manual valves are arranged one-to-one with the multiple perforation cluster modules. The electrically controlled back pressure valves are installed on the tubing column.

7. The visualization experimental device for flow transport in a fractured pipe with temporary plugging at the fracture opening, considering the stress shadowing effect of multiple perforations, as described in claim 6, is characterized in that... The recycling unit includes: A manifold, one end of which is open and the other end is closed; the manifold is connected to the second end of multiple manifolds; A recycling hose, the first end of which is connected to the open end of the manifold; A recycling storage tank is provided, and the second end of the recycling hose is connected to the recycling storage tank.

8. The visualization experimental device for flow transport in a temporarily plugged fracturing tube considering the stress shadowing effect of multiple perforations as described in claim 7, characterized in that, The well tilt lifting hydraulic unit includes: Base support frame; The transparent wellbore and the double-acting variable flow vane pump are fixedly installed on the upper support frame of the base; the first end of the upper support frame of the base is connected to the first end of the lower support frame of the base by a pin. A hydraulic assembly, wherein the fixed end of the hydraulic assembly is hinged to a non-end position of the lower support frame of the base, and the driving end of the hydraulic assembly is hinged to a non-end position of the upper support frame of the base, and the hydraulic assembly is used to change the included angle between the upper support frame of the base and the lower support frame of the base.

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