CN115898375A - A visual experimental device and method for particle migration to simulate fluid-solid coupling deformation of fractures - Google Patents

Abstract

The invention discloses a particle migration visualization experiment device and method for simulating fracture fluid-solid coupling deformation, including a wellbore flow simulation system, a fracture fluid-solid coupling deformation simulation system and a data acquisition system. The wellbore flow simulation system is provided with experimental fluid, The wellbore flow simulation system is connected with the fracture fluid-solid coupling deformation simulation system, and the particle migration and bridging behavior in different environments is simulated through the control valve and pressure regulating valve. Make a note. The present invention solves the problem that the particle migration and bridging behavior in the fracture space cannot be simulated in the prior art by simulating the fluid-solid coupling deformation of the fracture, and the particle migration and bridging behavior cannot be carried out. Direct observation is a technical problem that is difficult to deeply explore the bridging mechanism of particle migration.

Description

A visual experimental device and method for particle migration to simulate fluid-solid coupling deformation of fractures

technical field

The invention relates to the field of research on indoor experimental devices for drilling engineering, in particular to a particle migration visualization experimental device and method for simulating fluid-solid coupling deformation of fractures.

Background technique

In the exploration and development of deep oil and gas resources, natural fractures are widely distributed, and the problem of working fluid leakage is prominent, which has become one of the problems restricting safe and efficient well construction in deep formations. Due to the difficulty of predicting the distribution of downhole fractures and the complex spatial distribution of fractures, etc., downhole accidents such as one-time plugging difficulties and repeated leakages are often encountered. The main reason is that the understanding of the migration and bridging mechanism of solid particles in natural fractures is insufficient. . Therefore, a particle migration visualization experiment device and method for simulating fluid-solid coupling deformation of fractures is provided to explore the mechanism of rigid particle migration and bridging instability under the condition of fluid-solid coupling deformation in fractures, which can improve the natural rigid particle migration in fluid-solid coupling deformation. The understanding of the mechanical behavior in fractures provides an important theoretical basis for drilling and plugging on-site construction operations.

Chinese patent CN110295887A discloses an experimental device and working method for the visualization of particle migration laws. Combined with the results of 3D scanning of real cores, the transparent resin is 3D printed to obtain transparent rough fracture surfaces, and finally a set of particle migration visualization tools is constructed. Experimental device and method, but the device lacks consideration of formation conditions, does not consider the influence of fluid flow in the wellbore, and does not consider the fracture deformation.

Chinese patent CN106640061A proposes a wellbore and formation fracture coupling flow simulation experiment device and method, using a group of fracture plates carved based on natural fracture scanning results to connect the simulation wellbore to simulate the formation, and to study the coupling flow between the wellbore and formation fractures mechanism, but the device ignores the influence of formation fracture deformation on particle bridging migration, which will cause repeated leakage in field operations.

Contents of the invention

The purpose of the present invention is to provide a particle migration visualization experimental device and method for simulating fracture fluid-solid coupling deformation, to solve the problems in the prior art that cannot simulate the behavior of particle migration and bridging in the fracture space under the condition of formation fracture deformation. The migration and bridging behavior cannot be directly observed, and it is difficult to deeply explore the technical problem of the particle migration and bridging mechanism.

In order to achieve the above object, the present invention provides a particle migration visualization experimental device for simulating fluid-solid coupling deformation of fractures, including a wellbore flow simulation system, a fracture fluid-solid coupling deformation simulation system and a data acquisition system, characterized in that the wellbore The flow simulation system is connected with the fracture fluid-solid coupling deformation simulation system, and the data acquisition system records the experimental phenomena and liquid flow in the fracture fluid-solid coupling deformation simulation system;

The crack fluid-solid coupling deformation simulation system consists of transparent plexiglass slit plates, nuts, sealing gaskets, sealing pressure-bearing rubber plates, sealing rubber sleeves, detachable springs and bolts. The material is obtained by engraving. The two plexiglass transparent slit plates are arranged on both sides of the sealing and pressure-bearing rubber plate. A sealing rubber sleeve is arranged between the plexiglass transparent slit plate and the sealing and pressure-bearing rubber plate. The bolts pass through the two organic Glass transparent seam panels and sealed pressure-bearing rubber panels.

Further, the wellbore flow simulation system consists of an air compressor, connecting pipelines, control valves, pressure regulating valves and a simulated wellbore. The air compressor is connected to the simulated wellbore through a connecting pipeline; The driving element of the drive; the pressure regulating valve is the regulating element that applies a constant pressure to the whole device.

Furthermore, the simulated wellbore is connected to the fracture-fluid-solid coupling deformation simulation system through multiple connecting pipelines. The simulated wellbore is a vertical observation device made of transparent plexiglass round tubes, and the configured experimental fluid is injected into the simulated wellbore for simulation. The wellbore flows, and the experimental fluid enters the fracture fluid-solid coupling deformation simulation system through multiple connecting pipelines driven by pressure.

Further, a plurality of control valves and pressure adjustment valves are arranged on the connecting pipeline, and the plurality of control valves are divided into a valve V1 arranged between the air compressor and the pressure adjustment valve and a valve between the pressure adjustment valve and the simulated wellbore V2.

Further, a detachable spring is provided on the side of the bolt away from the thread, and the upper and lower plexiglass transparent seam plates are locked through the nut and the sealing gasket, and the nut and the bolt are flexibly connected through the thread, and the detachable spring By simulating the extrusion of organic glass transparent slit plates under different compression coefficients through the tightening of bolts, a dynamic deformation flow space is formed between two organic glass transparent slit plates.

Further, the data acquisition system is composed of a high-definition camera and a liquid flow metering device, the high-definition camera records the movement process of the particles in the transparent slit plate during the whole experiment, and the liquid flow metering device recovers and records the discharged liquid Drain flow.

Further, the liquid flow metering device is connected to the fracture fluid-solid coupling deformation simulation system through a connecting pipeline, and a control valve is set on the connecting pipeline, and the control valve set on the connecting pipeline between the liquid flow metering device and the fracture fluid-solid coupling deformation simulation system is Valve V3.

A particle migration visualization experimental method for simulating fluid-solid coupling deformation of fractures, comprising the following steps:

S1. Before the experiment, first determine the elastic modulus and Poisson's ratio of the formation rock mechanics parameters that need to be simulated. Based on this data, select a sealed pressure-bearing rubber plate with the same elastic modulus and Poisson's ratio to simulate the formation, and use the organic glass transparent seam plate and sealing The combination of pressure-bearing rubber plate and sealing rubber sleeve is fixed by 8 bolts and detachable springs;

S2. Before the experiment, put an appropriate amount of 1% CMC solution into the simulated wellbore, turn on the air compressor and all the control valves, and when the pressure is stabilized to 0.1MPa, then open the valve V2 and valve V3 at the same time, and continue to flow into the simulated wellbore. Pressurize to make the experimental base fluid in the simulated wellbore flow into the fracture fluid-solid coupling deformation simulation system, and ensure that there are no air bubbles in the control valve. Then, close the valve V2 and the valve V3 in turn, and finally use the pressure regulating valve to relieve the pressure;

S3. Inject the screened particle suspension with a certain particle size and concentration into the simulated wellbore, and then adjust the pressure regulating valve to keep the inlet pressure at 0.1Mpa. At the same time, adjust the high-definition camera to face the plexiglass transparent slit plate. Experimental records;

S4. Open the control valve V2 and valve V3 at the same time. The particle suspension in the simulated wellbore enters the fracture fluid-solid coupling deformation simulation system under the pressure drive. The inlet driving pressure can be controlled by the pressure regulating valve. When the inlet pressure increases, the fracture The pressure in the space will also increase accordingly. This increased pressure will help to resist the stress of the 8 detachable springs against the sealing pressure rubber plate, which is reflected in the increase of the opening of the space of the crack. Similarly, when the pressure gradually decreases , the opening of the fracture space will decrease again, and finally the dynamic deformation of the fracture space will be realized, and the migration and bridging behavior of solid particles in the fracture space will be observed at the same time;

S5. When the particle suspension in the simulated wellbore is about to be exhausted, close the valves V1 and V3 in turn, use the pressure regulating valve to relieve the pressure of the connecting pipeline, disassemble and clean the experimental pipeline and the fracture plate, and the experiment ends.

Based on the above technical scheme, the present invention can produce the following beneficial effects:

(1) The present invention provides a particle migration visualization experimental device and method for simulating fluid-solid coupling deformation of fractures. Using 3D engraving technology, based on the scanning results of natural cracks, the organic glass plate is engraved to obtain organic cracks including the morphology characteristics of natural cracks. The glass transparent slit plate, by selecting sealing rubber plates of different strengths and detachable springs, can realize fracture deformation under different formation conditions, and provide technical support for an accurate understanding of the formation process and mechanism of the fracture sealing area.

(2) The present invention provides a particle migration visualization experimental device and method for simulating fluid-solid coupling deformation of fractures. Experiments are carried out through the particle migration visualization experimental device for simulating fluid-solid coupling deformation of fractures, and high-definition cameras are used to monitor particles in cracks. The whole process of migration and bridging behavior in the space is recorded and analyzed, and the process of particle migration, bridging, instability, and re-migration and bridging in the deformed fracture can be observed. It provides technical means to explore the migration and bridging behavior under the condition of solid coupling deformation and its mechanism in depth.

Description of drawings

Fig. 1 is the structural representation of the embodiment of the present invention;

Fig. 2 is a structural schematic diagram of a fracture fluid-solid coupling deformation simulation system according to an embodiment of the present invention;

In the figure: 101, air compressor; 102, control valve; 103, pressure regulating valve; 104, connecting pipeline; 105, simulated wellbore; 201, plexiglass transparent slit plate; 202, nut; Sealing rubber plate; 205, sealing rubber sleeve; 206, detachable spring; 207, bolt; 301, high-definition camera; 302, liquid flow metering device.

Detailed ways

In order to better understand the purpose, structure and function of the present invention, a kind of particle migration visualization experimental device and method for simulating fluid-solid coupling deformation of fractures according to the present invention will be further described in detail below in conjunction with the accompanying drawings.

In the description of the present invention, it should be noted that the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", " The orientations or positional relationships indicated by "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying Describes, but does not indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation, and operate in a specific orientation, and therefore should not be construed as limiting the invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and should not be construed as indicating or implying relative importance.

As shown in the figure, a particle migration visualization experimental device for simulating fracture fluid-solid coupling deformation of the present invention includes a wellbore flow simulation system 1, a fracture fluid-solid coupling deformation simulation system 2, and a data acquisition system 3. It is characterized in that the wellbore The flow simulation system 1 is connected with the fracture fluid-solid coupling deformation simulation system 2, and the data acquisition system 3 records the experimental phenomena and liquid flow in the fracture fluid-solid coupling deformation simulation system.

Crack fluid-solid coupling deformation simulation system 2 is composed of plexiglass transparent slit plate 201, nut 202, sealing gasket 203, sealing pressure-bearing rubber plate 204, sealing rubber sleeve 205, detachable spring 206 and bolt 207. The plexiglass transparent slit plate 201 is obtained by engraving plexiglass material with an engraving machine. Two plexiglass transparent slit plates 201 are arranged on both sides of the sealing pressure-bearing rubber plate 204. The sealing rubber plate 204 can be made of different materials according to different experimental conditions to simulate different strata. Rock property, a sealing rubber sleeve 205 is arranged between the transparent plexiglass slit plate 201 and the sealing pressure-bearing rubber plate 204 , and the bolt 207 runs through the two plexiglass transparent slit plates 201 and the sealing and pressure-bearing rubber plate 204 .

Wellbore flow simulation system 1 is made up of air compressor 101, connecting pipeline 104, control valve 102, pressure regulating valve 103 and simulated wellbore 105, and air compressor 101 is connected with simulated wellbore 105 through connecting pipeline 104; Air compressor 101 is for the whole The device provides a pressure-driven driving element; the pressure regulating valve 103 is a regulating element that applies a constant pressure to the entire device.

The simulated wellbore 105 is connected to the fracture-fluid-solid coupling deformation simulation system through a plurality of connecting pipelines 104. The simulated wellbore 105 is a vertical observation device made of a transparent plexiglass tube, and the configured experimental fluid is injected into the simulated wellbore 105 for To simulate wellbore flow, the experimental fluid enters the fracture fluid-solid coupling deformation simulation system through a plurality of connecting pipelines 104 driven by pressure.

The connecting pipeline 104 is provided with multiple control valves 102 and pressure regulating valves 103, and the multiple control valves 102 are divided into valve V1 set between the air compressor 101 and the pressure regulating valve 103, and a valve V1 between the pressure regulating valve 103 and the simulated wellbore 105. Between the valve V2.

The bolt 207 is provided with a detachable spring 206 on the side away from the thread, and the upper and lower organic glass transparent seam plates 201 are locked by the nut 202 and the sealing gasket 203, and the nut 202 and the bolt 207 are movably connected by threads, which can The detachable spring 206 simulates the extrusion of the plexiglass transparent slit plate 201 under different compression coefficients through the tightness of the bolt 207. According to different experimental conditions, different detachable springs 206 can be selected. Between the two plexiglass transparent slit plates 201, a A fluid space that dynamically deforms.

The data acquisition system 3 is composed of a high-definition camera 301 and a liquid flow metering device 302. The high-definition camera 301 records the movement process of the particles in the transparent slit plate during the whole experiment, and the liquid flow metering device 302 recovers the discharged liquid and records the discharged liquid flow.

The liquid flow metering device 302 is connected to the fracture fluid-solid coupling deformation simulation system through the connecting pipeline 104, the connecting pipeline 104 is provided with a control valve 103, and the connecting pipeline 104 between the liquid flow metering device 302 and the fracture fluid-solid coupling deformation simulation system The set control valve 103 is valve V3.

The invention discloses a particle migration visualization experimental method for simulating fluid-solid coupling deformation of fractures, comprising the following steps:

S1. Before the experiment, first determine the elastic modulus and Poisson's ratio of the stratum rock mechanics parameters that need to be simulated. Based on this data, select the sealing pressure-bearing rubber plate 204 with the same elastic modulus and Poisson's ratio to simulate the stratum, and use the plexiglass transparent slit plate 201 Combined with the sealing and pressure-bearing rubber plate 204 and the sealing rubber sleeve 205, it is fixed by 8 bolts 207 and a detachable spring 206;

S2. Before the experiment, put an appropriate amount of 1% CMC solution into the simulated wellbore 105, open the air compressor 101 and all the control valves 102, and when the pressure is stabilized to 0.1MPa, then open the valve V2 and the valve V3 at the same time to simulate The pressure in the wellbore 105 is continuously pressurized, so that the experimental base fluid in the simulated wellbore 105 flows into the fracture fluid-solid coupling deformation simulation system 2, and it is ensured that no air bubbles exist in the control valve 102 . Subsequently, the valve V2 and the valve V3 are closed in sequence, and finally the pressure regulating valve 103 is used for pressure relief;

S3. Inject the screened particle suspension meeting a certain particle size and concentration into the simulated wellbore 105, and then adjust the pressure regulating valve 103 to keep the inlet pressure at 0.1Mpa. At the same time, adjust the high-definition camera 301 to face the organic glass transparent seam Board 201, for experiment recording;

S4. Simultaneously open the control valve V2 and valve V3, and the particle suspension in the simulated wellbore 105 enters the fracture fluid-solid coupling deformation simulation system driven by pressure. The inlet driving pressure can be controlled by the pressure regulating valve 103. When the inlet pressure increases , the pressure in the crack space will also increase accordingly, and this increased pressure will help the rubber plate 204 resist the pressure of the eight detachable springs 206 to resist the sealing pressure, which means that the opening of the crack space increases. Similarly, when the pressure When it gradually decreases, the opening of the fracture space will decrease again, and finally realize the dynamic deformation of the fracture space, and at the same time observe the migration and bridging behavior of solid particles in the fracture space;

S5. When the particle suspension in the simulated wellbore 105 is about to be exhausted, close the valves V1 and V3 in turn, use the pressure regulating valve 103 to relieve the pressure on the connecting pipeline 104, disassemble and clean the experimental pipeline and the fracture plate, and the experiment ends.

It can be understood that the present invention has been described through some embodiments, and those skilled in the art know that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, the features and examples may be modified to adapt a particular situation and material to the teachings of the invention without departing from the spirit and scope of the invention. Therefore, the present invention is not limited by the specific embodiments disclosed here, and all embodiments falling within the scope of the claims of the present application belong to the protection scope of the present invention.

Claims (8)

1. A particle migration visualization experimental device for simulating fluid-solid coupling deformation of fractures, including a wellbore flow simulation system (1), a fracture fluid-solid coupling deformation simulation system (2) and a data acquisition system (3), characterized in that the The wellbore flow simulation system (1) is connected to the fracture fluid-solid coupling deformation simulation system (2), and the data acquisition system (3) records the experimental phenomena and liquid flow in the fracture fluid-solid coupling deformation simulation system; The crack fluid-solid coupling deformation simulation system (2) consists of a plexiglass transparent slit plate (201), a nut (202), a sealing gasket (203), a sealing pressure bearing rubber plate (204), a sealing rubber sleeve (205), Composed of detachable springs (206) and bolts (207), the plexiglass transparent slit plate (201) is obtained by engraving the plexiglass material with an engraving machine, and the two plexiglass transparent slit plates (201) are arranged in a sealed pressure-bearing On both sides of the rubber plate (204), a sealing rubber sleeve (205) is provided between the organic glass transparent seam plate (201) and the sealing pressure rubber plate (204), and the bolt (207) runs through the two organic glass transparent seams plate (201) and sealing pressure-bearing rubber plate (204). 2. The particle migration visualization experimental device for simulating fluid-solid coupling deformation of fractures according to claim 1, characterized in that the wellbore flow simulation system (1) consists of an air compressor (101), connecting pipelines (104 ), a control valve (102), a pressure regulating valve (103) and a simulated wellbore (105), the air compressor (101) is connected to the simulated wellbore (105) through a connecting pipeline (104); the air compressor ( 101) is a drive element that provides pressure drive for the entire device; the pressure regulating valve (103) is an adjustment element that applies constant pressure to the entire device. 3. The particle migration visualization experimental device for simulating fluid-solid coupling deformation of fractures according to claim 2, characterized in that the simulated wellbore (105) is connected to the fluid-solid coupling deformation of fractures through multiple connecting pipelines (104) The simulated wellbore (105) is a vertical observation device made of a transparent plexiglass tube, and the configured experimental fluid is injected into the simulated wellbore (105) to simulate the flow of the wellbore. It enters the fracture fluid-solid coupling deformation simulation system through multiple connecting pipelines (104). 4. A visualized experimental device for particle migration that simulates fluid-solid coupling deformation in fractures according to claim 2, characterized in that the connecting pipeline (104) is provided with a plurality of control valves (102) and pressure regulating valves (103), the multiple control valves (102) are divided into valve V1 arranged between the air compressor (101) and the pressure regulating valve (103) and between the pressure regulating valve (103) and the simulated wellbore (105) valve V2. 5. The particle migration visualization experimental device for simulating fluid-solid coupling deformation of fractures according to claim 1, characterized in that a detachable spring (206) is provided on the side of the bolt (207) away from the thread, and through The nut (202) and the gasket (203) lock the upper and lower plexiglass transparent seam plates (201), and the nut (202) and the bolt (207) are connected through threads, and the detachable spring (206 ) Simulate the extrusion of the organic glass transparent slit plate (201) under different compression coefficients through the tightening of the bolt (207) and the deformation of the sealing rubber sleeve (205), and a gap is formed between two organic glass transparent slit plates (201). Dynamically deformable flow spaces. 6. The particle migration visualization experimental device for simulating fluid-solid coupling deformation of fractures according to claim 1, characterized in that the data acquisition system (3) consists of a high-definition camera (301) and a liquid flow metering device (302 ), the high-definition camera (301) records the movement behavior of the particles in the transparent slit plate during the whole experiment, and the liquid flow metering device (302) recovers the discharged liquid and records the discharged liquid flow. 7. The particle migration visualization experimental device for simulating fluid-solid coupling deformation of fractures according to claim 6, characterized in that the liquid flow metering device (302) is connected to the fluid-solid coupling deformation of fractures through a connecting pipeline (104) The simulation system is connected, the control valve (103) is set on the connecting pipeline (104), and the control valve (103) is set on the connecting pipeline (104) between the liquid flow metering device (302) and the fracture fluid-solid coupling deformation simulation system For valve V3. 8. A particle migration visualization experimental method for simulating fluid-solid coupling deformation of fractures, according to any one of claims 1 to 7, a particle migration visualization experimental device for simulating fluid-solid coupling deformation of fractures, characterized in that, It includes the following steps: S1. Before the experiment, first determine the elastic modulus and Poisson's ratio of the formation rock mechanics parameters that need to be simulated. Based on this data, select a sealed pressure-bearing rubber plate (204) with the same elastic modulus and Poisson's ratio to simulate the formation, and test the plexiglass transparent joint. The combination of plate (201), sealing pressure bearing rubber plate (204) and sealing rubber sleeve (205) is fixed by 8 bolts (207) and detachable spring (206); S2. Before the experiment, put an appropriate amount of 1% CMC solution into the simulated wellbore (105), turn on the air compressor (101) and all control valves (102), and when the pressure is stabilized to 0.1MPa, open the valve V2 at the same time With the valve V3, pressurize the simulated wellbore (105) continuously, so that the experimental base fluid in the simulated wellbore (105) flows into the fracture fluid-solid coupling deformation simulation system (2), and ensure that there are no air bubbles in the control valve (102) ; Subsequently, close the valve V2 and the valve V3 in turn, and finally use the pressure regulating valve (103) to relieve the pressure; S3. Inject the screened particle suspension meeting a certain particle size and concentration into the simulated wellbore (105), then adjust the pressure regulating valve (103) to keep the inlet pressure at 0.1Mpa, and at the same time adjust the high-definition camera (301), Facing the plexiglass transparent slit plate (201), the experiment record is carried out; S4. Simultaneously open the control valve V2 and valve V3, and the particle suspension in the simulated wellbore (105) enters the fracture fluid-solid coupling deformation simulation system under the pressure drive, and the inlet driving pressure can be controlled by the pressure regulating valve (103). When the inlet pressure increases, the pressure in the crack space will also increase accordingly, and this increased pressure will help to resist the stress of the sealing pressure-bearing rubber plate (204) against the 8 detachable springs (206), which is reflected in the opening of the crack space Similarly, when the pressure gradually decreases, the opening of the fracture space will decrease again, and finally realize the dynamic deformation of the fracture space, and at the same time observe the migration and bridging behavior of solid particles in the fracture space; S5. When the particle suspension in the simulated wellbore (105) is about to be exhausted, close the valves V1 and V3 in turn, use the pressure regulating valve (103) to relieve the pressure of the connecting pipeline (104), disassemble and clean the experimental pipeline and fractures plate, the end of the experiment.

Images