Competitive injection simulation system and method for fracturing

Abstract

The application discloses a kind of stereoscopic fracturing competitive injection simulation system and method, stereoscopic fracturing competitive injection simulation system includes fracturing wellbore equipment and fracturing fluid injection equipment, fracturing wellbore equipment, including multiple cluster perforating wellbore, perforating assembly and multiple sub-cluster injection pipeline, multiple first sub-cluster perforating group is set up in multiple cluster perforating wellbore, multiple first sub-cluster perforating group is sequentially spaced along the height direction of multiple cluster perforating wellbore, and each first sub-cluster perforating group includes multiple perforating modes, and selects one perforating mode to install perforating assembly, multiple sub-cluster injection pipeline is connected with the perforating assembly in multiple first sub-cluster perforating group one by one, the application can select different perforating assembly to realize multiple perforating modes and carry out comparative experiment, reduce manufacturing cost, improve experimental efficiency, and different quantity and different types of perforating assembly can meet the requirement of injection fracturing experiment to realize different azimuth angle perforating.

Description

Technical Field

[0001] This invention belongs to the field of petroleum fracturing construction technology, and particularly relates to a three-dimensional fracturing competitive injection simulation system and method. Background Technology

[0002] my country possesses enormous potential for the development of unconventional oil and gas resources, but conventional development methods are insufficient for the efficient development of unconventional reservoirs. Three-dimensional reservoir development is a development model based on the three-dimensional movement and driving laws of fluids, considering both horizontal and vertical forces on fluid seepage. This model is not limited to a single reservoir system or well pattern, but combines vertical and horizontal well patterns, employing a three-dimensional well network to develop reservoirs, thereby maximizing reservoir recovery and achieving high-level, high-efficiency development. It is suitable for thick or steeply dipping sandstone and shale reservoirs, and even more so for carbonate, volcanic, and metamorphic reservoirs with well-developed high-angle fractures. The principles of multi-layer three-dimensional development are: three-dimensional development, layered implementation, overall fracturing, and coordinated exploitation. In three-dimensional development, based on three-dimensional geological models and reserve distribution models, combined with geostress and natural fracture research technology, the goal is to carry out overall fracturing development. The key technologies involved include: three-dimensional stratigraphic description technology, geostress and natural fracture research technology, three-dimensional fracture simulation technology, multi-layer fracturing technology, and supporting fracturing construction technology.

[0003] With the successful application of hydraulic fracturing in unconventional oil and gas fields and the increasing difficulty of unconventional oil and gas extraction, the necessity for studying multi-cluster perforation fracturing is gradually increasing, placing higher demands on the accuracy of physical simulation experiments for multi-cluster perforation fracturing. To provide strong technical support for field fracturing design and construction schemes through experimental research, and to explore the influence of flow rate per cluster on fracture propagation morphology during multi-cluster perforation fracturing, indoor physical simulation experiments of hydraulic fracturing need to provide more accurate intra-cluster flow rate monitoring results. Traditional hydraulic fracturing experiments are difficult to perform perforations at different azimuth angles or simultaneously perform perforations with multiple different perforation modes. Summary of the Invention

[0004] In view of the above-mentioned defects or deficiencies of the prior art, the present invention provides a three-dimensional fracturing competitive injection simulation system, which aims to solve the technical problem that it is difficult to achieve perforation at different azimuth angles and to perform multiple different perforation modes simultaneously during hydraulic fracturing experiments.

[0005] To achieve the above objectives, the present invention provides a three-dimensional fracturing competitive injection simulation system, wherein the three-dimensional fracturing competitive injection simulation system includes fracturing wellbore equipment and fracturing fluid injection equipment. The fracturing wellbore equipment includes a multi-cluster perforated wellbore, a perforation assembly, and multiple cluster injection pipes. Multiple first cluster perforation groups are formed on the multi-cluster perforated wellbore. The multiple first cluster perforation groups are arranged sequentially at intervals along the height direction of the multi-cluster perforated wellbore, and each first cluster perforation group includes multiple perforation modes. The perforation assembly is installed using one of the perforation modes. The multiple cluster injection pipes are connected one-to-one with the perforation assemblies in the multiple first cluster perforation groups. The fracturing fluid injection equipment is used to inject fracturing fluid into the multiple cluster injection pipes respectively.

[0006] In this embodiment of the invention, the perforation assembly includes a perforation connector, a perforation tube, and multiple perforation modules with different perforation modes. The inner side of the multi-cluster perforation wellbore is equipped with one type of perforation module corresponding to each first cluster perforation group. The perforation module forms a liquid distribution space that communicates with the cluster injection pipeline. A second cluster perforation group that communicates with the liquid distribution space is opened on the periphery of the perforation module. The second cluster perforations in the second cluster perforation group are connected to a portion of the first cluster perforations in the first cluster perforation group to form perforation holes of the corresponding perforation modes. The perforation connector is installed in the perforation hole, and the perforation tube is connected to the perforation connector and extends out of the multi-cluster perforation wellbore.

[0007] In this embodiment of the invention, the perforation module has a threaded channel through which the clustered injection pipe passes, and the injection space is arranged around the threaded channel.

[0008] In this embodiment of the invention, a guide extending along the height direction is provided on the inner wall of the multi-cluster perforation wellbore, and a sliding member movably mounted on the guide is provided on the outer side of the perforation module, with the lower end of the guide corresponding to the first cluster perforation group.

[0009] In this embodiment of the invention, the perforation mode includes spiral perforation, fixed-face perforation and ultimate perforation, and / or, the fracturing well equipment also includes a perforation plugging component, which is used to seal the remaining perforation holes.

[0010] In this embodiment of the invention, the fracturing fluid injection equipment includes an injection pump group, a total pressure monitoring device, branch pipelines, a flow monitoring device, and a partial pressure monitoring device. The injection pump group is used to pump fracturing fluid in. The total pressure monitoring device is installed at the output end of the injection pump group and is used to monitor the total output pressure of the injection pump group. There are multiple branch pipelines, which connect multiple cluster injection pipelines to the output end of the injection pump group respectively. Each of the multiple branch pipelines is equipped with a flow monitoring device and a partial pressure monitoring device to monitor the branch flow rate and branch pressure of the corresponding branch pipeline respectively.

[0011] In this embodiment of the invention, the fracturing fluid injection equipment further includes a control device and a control valve. Control valves are installed on multiple branch pipelines. The control device is communicatively connected to the control valves, the flow monitoring device, and the partial pressure monitoring device, respectively. The control device is used to control the control valves based on the detection data of the flow monitoring device and the partial pressure monitoring device on each branch pipeline.

[0012] In this embodiment of the invention, the control device is configured to execute a natural flow allocation experiment method, which includes:

[0013] In each of the multiple first cluster perforation groups, one of the perforation modes is selected to install the perforation assembly.

[0014] Control the valve to open fully;

[0015] Receive the first detection data from the flow monitoring device and the pressure distribution monitoring device;

[0016] Obtain the fracture morphology of the first rock sample after fracturing experiment using a three-dimensional fracturing competitive injection simulation system;

[0017] Based on the first detection data and the fracture morphology of the first rock sample, the natural distribution data of fracturing fluid under different perforation modes were determined.

[0018] In this embodiment of the invention, the control device is configured to execute a fixed flow allocation experiment method, which includes:

[0019] In each of the multiple first cluster perforation groups, one of the perforation modes is selected to install the perforation assembly.

[0020] Adjust the opening of the control valve to maintain a constant flow rate in each branch pipeline;

[0021] Receive the second detection data from the flow monitoring device and the partial pressure monitoring device after multiple opening adjustments of the control valve;

[0022] The fracture morphology of the second rock sample was obtained after fracturing tests were conducted using a three-dimensional fracturing competitive injection simulation system with multiple adjustments to the control valve opening.

[0023] The optimal fixed flow rate under different perforation modes was determined based on the second detection data and the fracture morphology of the second rock sample.

[0024] In this embodiment of the invention, the control device is configured to perform a temporary plugging flow distribution experiment method for the seam opening, the temporary plugging flow distribution experiment method including:

[0025] In each of the multiple first cluster perforation groups, one of the perforation modes is selected to install the perforation assembly.

[0026] Control the closure of a branch pipeline's control valve and adjust the opening of two other control valves;

[0027] Receive the third detection data from the total pressure monitoring device and the partial pressure monitoring device after multiple adjustments to the control valve opening;

[0028] The fracture morphology of third rock samples was obtained after fracturing tests were conducted with different control valves closed using a three-dimensional fracturing competitive injection simulation system.

[0029] The optimal fixation pressure for temporary plugging of the perforation opening under different perforation modes was determined based on the third test data and the fracture morphology of the third rock sample.

[0030] To achieve the above objectives, the present invention includes a three-dimensional fracturing competitive injection simulation method, wherein the three-dimensional fracturing competitive injection simulation method employs the aforementioned three-dimensional fracturing competitive injection simulation system, and the three-dimensional fracturing competitive injection simulation method includes a natural flow distribution experimental method, which includes:

[0031] In each of the multiple first cluster perforation groups, one of the perforation modes is selected to install the perforation assembly.

[0032] Control the valve to open fully;

[0033] Receive the first detection data from the flow monitoring device and the pressure distribution monitoring device;

[0034] Obtain the fracture morphology of the first rock sample after fracturing experiment using a three-dimensional fracturing competitive injection simulation system;

[0035] Based on the first detection data and the fracture morphology of the first rock sample, the natural distribution data of fracturing fluid under different perforation modes were determined.

[0036] In this embodiment of the invention, the three-dimensional fracturing competitive injection simulation method further includes a fixed flow rate distribution experiment method, which includes:

[0037] In each of the multiple first cluster perforation groups, one of the perforation modes is selected to install the perforation assembly.

[0038] Adjust the opening of the control valve to maintain a constant flow rate in each branch pipeline;

[0039] Receive the second detection data from the flow monitoring device and the partial pressure monitoring device after multiple opening adjustments of the control valve;

[0040] The fracture morphology of the second rock sample was obtained after fracturing tests were conducted using a three-dimensional fracturing competitive injection simulation system with multiple adjustments to the control valve opening.

[0041] The optimal fixed flow rate under different perforation modes was determined based on the second detection data and the fracture morphology of the second rock sample.

[0042] In this embodiment of the invention, the three-dimensional fracturing competitive injection simulation method further includes a fracture orifice temporary plugging flow distribution experimental method, which includes:

[0043] In each of the multiple first cluster perforation groups, one of the perforation modes is selected to install the perforation assembly.

[0044] Control the closure of a branch pipeline's control valve and adjust the opening of two other control valves;

[0045] Receive the third detection data from the total pressure monitoring device and the partial pressure monitoring device after multiple adjustments to the control valve opening;

[0046] The fracture morphology of third rock samples was obtained after fracturing tests were conducted with different control valves closed using a three-dimensional fracturing competitive injection simulation system.

[0047] The optimal fixation pressure for temporary plugging of the perforation opening under different perforation modes was determined based on the third test data and the fracture morphology of the third rock sample.

[0048] Through the above technical solutions, the three-dimensional fracturing competitive injection simulation system provided in this embodiment of the invention has the following beneficial effects:

[0049] When using the above-mentioned three-dimensional fracturing competitive injection simulation system, since it includes fracturing wellbore equipment and fracturing fluid injection equipment, the fracturing wellbore equipment includes a multi-cluster perforated wellbore, perforation components, and multiple cluster injection pipelines. Multiple first-cluster perforation groups are formed on the multi-cluster perforated wellbore, and these groups are sequentially spaced along the height direction of the wellbore. Each first-cluster perforation group can form multiple perforation patterns, and a perforation component can be installed within the multi-cluster perforated wellbore corresponding to each first-cluster perforation group. Different types of perforation components can be combined with the first-cluster perforations to form different perforation patterns. Multiple cluster injection pipelines are connected one-to-one with the perforation components within the multiple first-cluster perforation groups. Compared to the prior art which uses a single perforation component to achieve a single perforation pattern for injection fracturing experiments, this invention allows for the selection of different types of perforation components to achieve multiple perforation patterns for comparative experiments, reducing manufacturing costs and improving experimental efficiency. Different numbers and types of perforation components can meet the requirements of injection fracturing experiments to achieve perforations at different azimuth angles.

[0050] Other features and advantages of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0051] The accompanying drawings are provided to illustrate the invention and form part of the specification. They are used together with the following detailed description to explain the invention, but do not constitute a limitation thereof. In the drawings:

[0052] Figure 1This is a schematic diagram of the working principle of the three-dimensional fracturing competitive fluid injection simulation system according to an embodiment of the present invention;

[0053] Figure 2 This is a diagram showing the usage status of the fracturing wellbore equipment according to an embodiment of the present invention;

[0054] Figure 3 This is a schematic diagram of the structure of a fracturing wellbore equipment according to an embodiment of the present invention;

[0055] Figure 4 This is a schematic diagram of the structure of a multi-cluster perforated wellbore according to an embodiment of the present invention;

[0056] Figure 5 It is based on Figure 4 A sectional view;

[0057] Figure 6 This is a schematic diagram of the perforation module according to an embodiment of the present invention;

[0058] Figure 7 It is based on Figure 6 A sectional view;

[0059] Figure 8 This is a partial structural schematic diagram of the fracturing fluid injection device according to an embodiment of the present invention.

[0060] Explanation of reference numerals in the attached figures

[0061] 100 Fracturing wellbore equipment; 101 Multi-cluster perforated wellbore.

[0062] 102 Perforation assembly 103 Perforation connector

[0063] 104 Perforating tube 105 Perforating module

[0064] 106 Cluster injection pipeline 107 First cluster perforation group

[0065] 108 Second cluster perforation group 110 Threading channel

[0066] 111 Separation space 112 Guide component

[0067] 113 Sliding component 114 Perforation plugging component

[0068] 200 Fracturing fluid injection equipment; 201 Injection pump set

[0069] 202 Total pressure monitoring device; 203 Flow monitoring device

[0070] 204 Pressure monitoring device 205 Pipeline

[0071] 206 Control Valve 300 Sample Detailed Implementation

[0072] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0073] my country possesses enormous potential for the development of unconventional oil and gas resources, and hydraulic fracturing is currently one of the most commonly used reservoir stimulation techniques for the efficient development of unconventional oil and gas resources. Three-dimensional reservoir development is a development model based on the three-dimensional movement and driving laws of fluids, considering both horizontal and vertical forces on fluid seepage. This development model is not limited to a single reservoir system or well pattern, but combines vertical and horizontal well patterns, employing a three-dimensional well network to develop reservoirs, thereby maximizing reservoir recovery and achieving high-level, high-efficiency development. It is suitable for thick or steeply dipping sandstone and shale reservoirs, and even more so for carbonate, volcanic, and metamorphic reservoirs with well-developed high-angle fractures. The principles of multi-layer three-dimensional development are: three-dimensional development, layered implementation, overall fracturing, and coordinated exploitation. In three-dimensional development, based on three-dimensional geological models and reserve distribution models, combined with geostress and natural fracture research technology, the goal is to carry out overall fracturing development. The key technologies involved include: three-dimensional stratigraphic description technology, geostress and natural fracture research technology, three-dimensional fracture simulation technology, multi-layer fracturing technology, and supporting fracturing construction technology.

[0074] With the successful application of hydraulic fracturing in unconventional oil and gas fields and the increasing difficulty of unconventional oil and gas extraction, the necessity for studying multi-cluster perforation fracturing is gradually increasing, placing higher demands on the accuracy of physical simulation experiments for multi-cluster perforation fracturing. To provide strong technical support for field fracturing design and construction schemes through experimental research, and to explore the influence of flow rate per cluster on fracture propagation morphology during multi-cluster perforation fracturing, indoor physical simulation experiments of hydraulic fracturing need to provide more accurate monitoring results of intra-cluster flow rate. Traditional hydraulic fracturing experiments struggle to achieve perforation at different azimuth angles and control the fracturing fluid flow rate within different clusters.

[0075] Based on this, the present application provides a three-dimensional fracturing competitive injection simulation system, which aims to solve the technical problems of difficulty in achieving perforation at different azimuth angles and controlling the flow rate of fracturing fluid in different clusters during hydraulic fracturing experiments.

[0076] The three-dimensional fracturing competitive injection simulation system according to the present invention is described below with reference to the accompanying drawings.

[0077] like Figures 1 to 4 As shown, in an embodiment of the present invention, a three-dimensional fracturing competitive injection simulation system is provided, wherein the three-dimensional fracturing competitive injection simulation system includes:

[0078] The fracturing wellbore equipment 100 includes a multi-cluster perforated wellbore 101, a perforation assembly 102, and multiple clustered injection pipes 106. Multiple first clustered perforation groups 107 are provided on the multi-cluster perforated wellbore 101. The multiple first clustered perforation groups 107 are arranged sequentially at intervals along the height direction of the multi-cluster perforated wellbore 101. Each first clustered perforation group 107 includes multiple perforation modes, and the perforation assembly 102 is installed using one of the perforation modes. The multiple clustered injection pipes 106 are connected one-to-one with the perforation assemblies 102 in the multiple first clustered perforation groups 107.

[0079] The fracturing fluid injection device 200 is used to inject fracturing fluid into multiple first cluster injection pipes 106 respectively.

[0080] When using the above-mentioned three-dimensional fracturing competitive injection simulation system, since it includes fracturing wellbore equipment 100 and fracturing fluid injection equipment 200, the fracturing wellbore equipment 100 includes a multi-cluster perforated wellbore 101, a perforation assembly 102, and multiple cluster injection pipes 106. Multiple first cluster perforation groups 107 are formed on the multi-cluster perforated wellbore 101, and these groups are sequentially spaced along the height direction of the multi-cluster perforated wellbore 101. Each first cluster perforation group 107 can form multiple perforation patterns, and one perforation group can be installed within the multi-cluster perforated wellbore 101 corresponding to each first cluster perforation group 107. The component 102 can be combined with different types of perforation components 102 to form different perforation patterns when used in conjunction with the first cluster perforation. Multiple cluster injection pipes 106 are connected one-to-one with the perforation components 102 in multiple first cluster perforation groups 107. Compared with the prior art, which uses a single perforation component 102 to achieve a single perforation pattern for injection hydraulic fracturing experiments, the present invention can select different types of perforation components 102 to achieve multiple perforation patterns for comparative experiments, reducing manufacturing costs and improving experimental efficiency. Different numbers and types of perforation components 102 can meet the requirements of injection hydraulic fracturing experiments to achieve perforation at different azimuth angles. It should be noted that in this invention, the spacing between two adjacent first sub-cluster perforation groups 107 can be changed by replacing the multi-cluster perforation wellbore 101, so as to design and manufacture multi-cluster perforation wellbores 101 with different cluster spacing to achieve close-cut fracturing. Furthermore, the multi-cluster perforation wellbore 101 is fixed in the sample 300 during perforation. The material of the sample 300 is mainly concrete rock sample, but it can also be combined with outcrop rock sample or other artificial rock sample. Multiple multi-cluster perforation wellbores 101 can be pre-embedded in the sample 300, and multiple multi-cluster perforation wellbores 101 can be connected to the fracturing fluid injection device 200 through multiple pipelines to obtain more comprehensive experimental data.

[0081] See Figure 3 , Figure 6 and Figure 7In this embodiment of the invention, the perforation assembly 102 includes a perforation connector 103, a perforation tube 104, and multiple perforation modules 105 with different perforation modes. The inner side of the multi-cluster perforation wellbore 101 is equipped with one type of perforation module 105 corresponding to each first cluster perforation group 107. The perforation module 105 forms a liquid distribution space 111 communicating with the cluster injection pipe 106, and a second cluster perforation group communicating with the liquid distribution space 111 is opened on the periphery of the perforation module 105. 108. The second cluster perforations in the second cluster perforation group 108 are connected to a portion of the first cluster perforations in the first cluster perforation group 107 to form perforation orifices of corresponding perforation patterns. That is, the first cluster perforation group 107 of the multi-cluster perforation wellbore 101 has different perforation pattern arrangements, while the perforation module 105 has only one perforation pattern arrangement. The perforation connector 103 is installed inside the perforation orifice, and the perforation tube 104 is connected to the perforation connector 103 and extends out of the multi-cluster perforation wellbore 101. In other words, by replacing the perforation module 105 of the second cluster perforation group 108 with different perforation pattern arrangements with the first cluster perforation group 107, the perforation connector 103, and the perforation tube 104, perforation orifices of different perforation patterns can be combined to form perforation orifices of different patterns, which can quickly realize the switching of multiple perforation patterns and provide the conditions for three-dimensional fracturing injection simulation experiments.

[0082] Specifically, the perforation connector 103 passes through the outer wall of the multi-cluster perforation wellbore 101 and is inserted into the second cluster perforation group 108, so that the perforation connector 103 connects the liquid distribution space 111 of the perforation module 105 with the outside of the multi-cluster perforation wellbore 101. The perforation connector 103 forms a pipeline channel for the perforation tube 104 to pass through. The outer end of the perforation tube 104 is located outside the multi-cluster perforation wellbore 101, and the inner end of the perforation tube 104 is inserted into the pipeline channel of the perforation connector 103.

[0083] See Figure 6 and Figure 7 In an embodiment of the present invention, the perforation module 105 has a threaded channel 110 through which the clustered injection pipe 106 passes, and a distribution space 111 is arranged around the threaded channel 110. That is, the threaded channel 110 serves to constrain the clustered injection pipe 106 within the perforation module 105, and the annular distribution space 111 ensures that the second clustered perforation group 108 opened on the periphery of the perforation module 105 can be replenished with the fracturing fluid required for perforation in a timely manner, so as to ensure the normal progress of the perforation fracturing experiment.

[0084] Specifically, the threading channel 110 is a cylindrical channel and is coaxial with the perforation module 105, so that the clustered injection pipe 106 can pass smoothly through the threading channel 110 of the perforation module 105. The coaxial design of the threading channel 110 and the perforation module 105 makes the resulting liquid distribution space 111 have the same radial width in all directions, which can provide the same fracturing fluid conditions to the multiple perforation joints 103 connected to the liquid distribution space 111.

[0085] See Figure 5 and Figure 6 In an embodiment of the present invention, a guide member 112 extending along the height direction is provided on the inner wall of the multi-cluster perforation wellbore 101, and a sliding member 113 movably mounted on the guide member 112 is provided on the outer side of the perforation module 105. The lower end of the guide member 112 corresponds to the first cluster perforation group 107. That is, the perforation module 105 moves to the end of the sliding member 113 inside the multi-cluster perforation wellbore 101 via the guide member 112, so as to realize the rapid docking of the second cluster perforation with the corresponding first cluster perforation, which can improve the installation efficiency and accuracy of the perforation module 105.

[0086] Specifically, the guide 112 is a groove formed on the inner wall of the multi-cluster perforation wellbore 101, and the sliding member 113 is a slider fixedly installed on the outside of the perforation module 105. There are three sets of grooves, and the end of each set of grooves corresponds to the position of the first sub-cluster perforation of each set. There are two grooves in each set, and the two grooves in each set are symmetrically arranged about the axis of the multi-cluster perforation wellbore 101. The sliders on the perforation module 105 are two symmetrically arranged to cooperate with each set of grooves, which can improve the stability of the perforation module 105 in the multi-cluster perforation wellbore 101.

[0087] See Figure 3 In embodiments of the present invention, the perforation modes include spiral perforation, fixed-plane perforation, and extreme perforation. Correspondingly, the perforation module 105 includes a spiral perforation module, a fixed-plane perforation module, and an extreme perforation module. The second cluster perforation group 108 on the spiral perforation module is connected to the corresponding hole position on the first cluster perforation group 107 to realize spiral perforation. The second cluster perforation group 108 on the fixed-plane perforation module is connected to the corresponding hole position on the first cluster perforation group 107 to realize fixed-plane perforation. The second cluster perforation group 108 on the extreme perforation module is connected to the corresponding hole position on the first cluster perforation group 107 to realize extreme perforation.

[0088] In an embodiment of the present invention, the fracturing wellbore equipment 100 further includes a perforation plugging member 114, which is used to seal the remaining perforations. Specifically, the perforation plugging member 114 is a solid structure relative to the perforation connector 103, without forming a pipeline channel, to seal the first cluster perforations on the multi-cluster perforated wellbore 101 that do not have perforation pipes 104. The perforation plugging member 114 and the first cluster perforations are sealed together by an O-ring. Specifically, when spiral perforation is required, a perforation connector 103 and a perforation tube 104 are installed on the first cluster of perforations that can form a spiral structure on the multi-cluster perforation wellbore 101, and the remaining first cluster perforations are sealed with a perforation plug 114, so that the fracturing fluid ejected from the perforation tube 104 can form spiral perforations on the rock sample. Furthermore, when fixed-surface perforation is required, perforations are installed on the first cluster of perforations that can form a planar structure parallel to, perpendicular to, or at any angle to the multi-cluster perforation wellbore 101. The joint 103 and perforation pipe 104 are installed, and the remaining first cluster perforations are sealed with perforation plug 114 so that the fracturing fluid ejected from the perforation pipe 104 can form a fixed-surface perforation on the rock sample. Furthermore, when extreme perforation is required, the number of first cluster perforations participating in perforation on the multi-cluster perforation wellbore 101 is changed and the perforation joint 103 and perforation pipe 104 are installed, and the remaining first cluster perforations are sealed with perforation plug 114 to increase the injection intensity of the fracturing fluid ejected from the perforation pipe 104 and form extreme perforation on the rock sample.

[0089] See Figure 1 , Figure 2 and Figure 8 In an embodiment of the present invention, the fracturing fluid injection device 200 includes an injection pump group 201, a total pressure monitoring device 202, branch lines 205, a flow monitoring device 203, and a partial pressure monitoring device 204. The injection pump group 201 is used to pump fracturing fluid. The total pressure monitoring device 202 is installed at the output end of the injection pump group 201 and is used to monitor the total output pressure of the injection pump group 201. There are multiple branch lines 205, which connect multiple cluster injection pipes 106 to the output end of the injection pump group 201 respectively. Each of the multiple branch lines 205 is equipped with a flow monitoring device 203 and a partial pressure monitoring device 204 to monitor the branch flow rate and branch pressure of the corresponding branch line 205 respectively. That is, the flow rate and pressure flowing into each cluster injection pipe 106 can be controlled by the flow monitoring device 203 and the partial pressure monitoring device 204, so as to study the influence of different flow rates and pressures in different cluster injection pipes 106 on the crack propagation morphology.

[0090] Specifically, the flow monitoring device 203 includes a flow meter installed on multiple branch lines 205 to monitor the flow rate of fracturing fluid in each branch line 205, and the pressure monitoring device 204 includes a pressure meter installed on multiple branch lines 205 to monitor the pressure of fracturing fluid in each branch line 205.

[0091] See Figure 1 and Figure 8 In an embodiment of the present invention, the fracturing fluid injection device 200 further includes a control device and a control valve 206. Each of the multiple branch pipelines 205 is equipped with a control valve 206. The control device is communicatively connected to the control valve 206, the flow monitoring device 203, and the partial pressure monitoring device 204, respectively. The control device controls the control valve 206 based on the detection data from the flow monitoring device 203 and the partial pressure monitoring device 204 on each branch pipeline 205. That is, the control device controls the opening degree of the electrically controlled valve by collecting and calculating electrical signals from the flow monitoring device 203 and the partial pressure monitoring device 204, thereby achieving dynamic regulation of the flow rate and pressure within each cluster injection pipeline 106.

[0092] See Figure 1 , Figure 3 , Figure 4 and Figure 8 In an embodiment of the present invention, the control device is configured to perform a natural flow allocation experiment method, the natural flow allocation experiment method comprising:

[0093] In each of the multiple first cluster perforation groups 107, one of the perforation modes is selected to install the perforation assembly 102;

[0094] Control valve 206 is fully opened;

[0095] Receive the first detection data from the flow monitoring device 203 and the partial pressure monitoring device 204;

[0096] Obtain the fracture morphology of the first rock sample after fracturing experiment using a three-dimensional fracturing competitive injection simulation system;

[0097] Based on the first detection data and the fracture morphology of the first rock sample, the natural distribution data of fracturing fluid under different perforation modes were determined.

[0098] When the above-mentioned natural flow distribution experimental method is used, the relationship between natural flow and pressure state and the perforation fracture morphology of the rock sample by the perforation module 105 is obtained. The control valve 206 is fully open and not working, and only the flow and pressure in each cluster injection pipe 106 are monitored. The natural distribution law of fracturing fluid flow in each perforation cluster during close-cut fracturing is analyzed in combination with the fracture morphology of the rock sample after fracturing and the flow and pressure parameters.

[0099] See Figure 1 , Figure 3, Figure 4 and Figure 8 In an embodiment of the present invention, the control device is configured to perform a fixed flow rate allocation experiment method, which includes:

[0100] In each of the multiple first cluster perforation groups 107, one of the perforation modes is selected to install the perforation assembly 102;

[0101] Adjust the opening of control valve 206 to maintain a constant flow rate in each branch line 205;

[0102] Receive the second detection data from the flow monitoring device 203 and the partial pressure monitoring device 204 after multiple opening adjustments of the control valve 206;

[0103] The fracture morphology of the second rock sample was obtained after fracturing tests were conducted by the three-dimensional fracturing competitive injection simulation system with multiple opening adjustments of control valve 206.

[0104] The optimal fixed flow rate under different perforation modes was determined based on the second detection data and the fracture morphology of the second rock sample.

[0105] When using the aforementioned fixed flow rate distribution experimental method, the relationship between different flow rates and pressures and the perforation fracture morphology of the rock sample by the perforation module 105 is obtained. This determines the optimal flow rate and pressure within the cluster injection pipeline 106. The second detection data corresponding to the optimal fracture morphology of the second rock sample is the optimal fixed flow rate. By coordinating the flow monitoring device 203 and the control valve 206, a fixed flow rate is set for each cluster injection pipeline 106. The fracturing effect of the rock sample under different schemes is quantitatively analyzed, thereby finding the optimal inter-cluster flow rate distribution scheme for close-cut fracturing.

[0106] See Figure 1 , Figure 3 , Figure 4 and Figure 8 In an embodiment of the present invention, the control device is configured to perform a temporary plugging flow distribution experiment method for the seam opening, the temporary plugging flow distribution experiment method including:

[0107] In each of the multiple first cluster perforation groups 107, one of the perforation modes is selected to install the perforation assembly 102;

[0108] Control valve 206 of one branch line 205 is closed and the opening of the other two control valves 206 is adjusted;

[0109] Receive the third detection data from the total pressure monitoring device 202 and the partial pressure monitoring device 204 after multiple opening adjustments of the control valve 206;

[0110] The fracture morphology of the third rock sample was obtained after fracturing tests were conducted with different control valves 206 closed using a three-dimensional fracturing competitive injection simulation system.

[0111] The optimal fixation pressure for temporary plugging of the perforation opening under different perforation modes was determined based on the third test data and the fracture morphology of the third rock sample.

[0112] When using the above-mentioned fracture temporary plugging flow distribution experimental method, the experiment is first conducted according to the natural distribution method. When one or more cluster injection pipelines 106 have a large flow rate while other cluster injection pipelines 106 have a very small flow rate, the opening of the control valve 206 on the branch pipeline 205 corresponding to the cluster injection pipeline 106 with the large flow rate is reduced, and an artificial resistance is applied to simulate fracture temporary plugging construction, that is, different control valves 206 are closed, so that the corresponding perforation module 105 does not perforate. Based on the third rock sample fracture morphology and third detection data generated by the remaining perforation module 105 on the rock sample, the relationship between rock sample fractures and the closure of different control valves 206 under fixed pressure conditions is analyzed. The third detection data corresponding to the best third rock sample fracture morphology is the optimal fixed pressure. A fixed bottom hole and fracture pressure difference is set for each cluster injection pipeline 106 through the total pressure monitoring device 202 and the partial pressure monitoring device 204, and the reservoir stimulation effect under different fracture temporary plugging effects is simulated in conjunction with the control valves 206.

[0113] Specifically, the sample preparation can reflect a multi-layer system, that is, using concrete samples 300 with different formulations to simulate the three-dimensional fracturing development conditions of reservoirs with different physical properties. Furthermore, multiple multi-cluster perforated wellbores 101 can be pre-embedded in the sample 300 and connected to the injection pump group 201 through multiple pipelines. When preparing the multi-cluster perforated wellbores 101, the placement of the multi-cluster perforated wellbores 101 in the layer position of the sample 300 can be controlled by changing the length of the multi-cluster perforated wellbores 101 to simulate the vertical multi-layer three-dimensional development conditions. At the same time, by changing the relative positions between the multi-cluster perforated wellbores 101, the three-dimensional fracturing development effect of the reservoir under different well patterns and well spacing conditions can be simulated. Furthermore, by controlling the control valve 206 on the branch pipeline 205 connecting the multi-cluster perforated wellbores 101 and the injection pump group 201, the overall transformation effect of different well patterns on the reservoir under different flow rates can be studied, providing reliable experimental basis for the preparation of three-dimensional development schemes in engineering practice.

[0114] To achieve the above objectives, the present invention includes a three-dimensional fracturing competitive injection simulation method, wherein the three-dimensional fracturing competitive injection simulation method employs the aforementioned three-dimensional fracturing competitive injection simulation system, and the three-dimensional fracturing competitive injection simulation method includes a natural flow distribution experimental method, which includes:

[0115] In each of the multiple first cluster perforation groups 107, one of the perforation modes is selected to install the perforation assembly 102;

[0116] Control valve 206 is fully opened;

[0117] Receive the first detection data from the flow monitoring device 203 and the partial pressure monitoring device 204;

[0118] Obtain the fracture morphology of the first rock sample after fracturing experiment using a three-dimensional fracturing competitive injection simulation system;

[0119] Based on the first detection data and the fracture morphology of the first rock sample, the natural distribution data of fracturing fluid under different perforation modes were determined.

[0120] When the above-mentioned natural flow distribution experimental method is used, the relationship between natural flow and pressure state and the perforation fracture morphology of the rock sample by the perforation module 105 is obtained. The control valve 206 is fully open and not working, and only the flow and pressure in each cluster injection pipe 106 are monitored. The natural distribution law of fracturing fluid flow in each perforation cluster during close-cut fracturing is analyzed in combination with the fracture morphology of the rock sample after fracturing and the flow and pressure parameters.

[0121] In embodiments of the present invention, the three-dimensional fracturing competitive injection simulation method further includes a fixed flow rate distribution experimental method, which includes:

[0122] In each of the multiple first cluster perforation groups 107, one of the perforation modes is selected to install the perforation assembly 102;

[0123] Adjust the opening of control valve 206 to maintain a constant flow rate in each branch line 205;

[0124] Receive the second detection data from the flow monitoring device 203 and the partial pressure monitoring device 204 after multiple opening adjustments of the control valve 206;

[0125] The fracture morphology of the second rock sample was obtained after fracturing tests were conducted by the three-dimensional fracturing competitive injection simulation system with multiple opening adjustments of control valve 206.

[0126] The optimal fixed flow rate under different perforation modes was determined based on the second detection data and the fracture morphology of the second rock sample.

[0127] When using the aforementioned fixed flow rate distribution experimental method, the relationship between different flow rates and pressures and the perforation fracture morphology of the rock sample by the perforation module 105 is obtained. This determines the optimal flow rate and pressure within the cluster injection pipeline 106. The second detection data corresponding to the optimal fracture morphology of the second rock sample is the optimal fixed flow rate. By coordinating the flow monitoring device 203 and the control valve 206, a fixed flow rate is set for each cluster injection pipeline 106. The fracturing effect of the rock sample under different schemes is quantitatively analyzed, thereby finding the optimal inter-cluster flow rate distribution scheme for close-cut fracturing.

[0128] In embodiments of the present invention, the three-dimensional fracturing competitive injection simulation method further includes a fracture orifice temporary plugging flow distribution experimental method, which includes:

[0129] In each of the multiple first cluster perforation groups 107, one of the perforation modes is selected to install the perforation assembly 102;

[0130] Control valve 206 of one branch line 205 is closed and the opening of the other two control valves 206 is adjusted;

[0131] Receive the third detection data from the total pressure monitoring device 202 and the partial pressure monitoring device 204 after multiple opening adjustments of the control valve 206;

[0132] The fracture morphology of the third rock sample was obtained after fracturing tests were conducted with different control valves 206 closed using a three-dimensional fracturing competitive injection simulation system.

[0133] The optimal fixation pressure for temporary plugging of the perforation opening under different perforation modes was determined based on the third test data and the fracture morphology of the third rock sample.

[0134] When using the above-mentioned fracture temporary plugging flow distribution experimental method, the experiment is first conducted according to the natural distribution method. When one or more cluster injection pipelines 106 have a large flow rate while other cluster injection pipelines 106 have a very small flow rate, the opening of the control valve 206 on the branch pipeline 205 corresponding to the cluster injection pipeline 106 with the large flow rate is reduced, and an artificial resistance is applied to simulate fracture temporary plugging construction, that is, different control valves 206 are closed, so that the corresponding perforation module 105 does not perforate. Based on the third rock sample fracture morphology and third detection data generated by the remaining perforation module 105 on the rock sample, the relationship between rock sample fractures and the closure of different control valves 206 under fixed pressure conditions is analyzed. The third detection data corresponding to the best third rock sample fracture morphology is the optimal fixed pressure. A fixed bottom hole and fracture pressure difference is set for each cluster injection pipeline 106 through the total pressure monitoring device 202 and the partial pressure monitoring device 204, and the reservoir stimulation effect under different fracture temporary plugging effects is simulated in conjunction with the control valves 206.

[0135] Specifically, the experimental steps for using the three-dimensional fracturing competitive injection simulation system are as follows:

[0136] Step 1: Connect the multiple clustered injection pipes 106 one by one to the perforation module 105, and place the perforation module 105 into the multi-cluster perforation wellbore 101 from bottom to top along the sliding groove on the inner wall of the multi-cluster perforation wellbore 101, and ensure that the positions of the second cluster perforation correspond to the first cluster perforation.

[0137] Step 2: According to the determined perforation pattern, install the perforation connector 103 onto the corresponding first cluster perforation, then install the perforation tube 104 onto the perforation connector 103, and the perforation plug 114 seals the remaining first cluster perforations.

[0138] Step 3: Place the multi-cluster perforated well casing 101, which has completed the above steps, into the center of the cement mold, and fill the mold with cement until the sample 300 reaches the size of 300mm×300mm×300mm.

[0139] Step 4: Wait for the cement to fully harden and encapsulate the multi-cluster perforated well casing 101;

[0140] Step 5: Place the sample 300 into the true triaxial hydraulic fracturing physical simulation experimental system and install the pressure plate and fracturing fluid injection device 200;

[0141] Step 6: Connect the multi-cluster injection pipeline to the fracturing fluid injection equipment 200;

[0142] Step 7: Turn on the triaxial confining pressure loading system and apply triaxial confining pressure to the experimental sample, trying to maintain the triaxial confining pressure in a balanced manner.

[0143] Step 8: Turn on the fracturing fluid injection equipment 200, inject the pre-prepared experimental fluid according to the established experimental plan, and record the pressure-time relationship, flow rate and pressure distribution in each cluster injection pipeline 106 on the computer.

[0144] Step 9: After the injection pressure-time curve shows a significant decrease, the experiment ends. First, shut down the fracturing fluid injection device 200, then operate the confining pressure loading pump group to perform a three-way confining pressure relief operation. After the pressure relief is completed, disconnect the multi-cluster injection pipeline from the fracturing fluid injection device 200.

[0145] Step 10: Remove sample 300 from the true triaxial hydraulic fracturing physical simulation experimental system and destroy sample 300. Observe the fracture morphology formed in sample 300. Combine the fluid flow rate and fluid pressure in each cluster injection pipe 106 recorded by the computer to analyze the relationship between fracture morphology and flow rate and pressure distribution.

[0146] In the description of this invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0147] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0148] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0149] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A three-dimensional fracturing competitive fluid injection simulation system, characterized in that, The three-dimensional fracturing competitive injection simulation system comprises: The fracturing wellbore equipment (100) comprises a multi-cluster perforation wellbore (101), a perforation assembly (102) and a plurality of cluster injection pipelines (106), a plurality of first cluster perforation groups (107) are arranged on the multi-cluster perforation wellbore (101), the plurality of first cluster perforation groups (107) are arranged in sequence and at intervals along the height direction of the multi-cluster perforation wellbore (101), each of the first cluster perforation groups (107) comprises a plurality of perforation modes, and the perforation assembly (102) is installed in one of the perforation modes; the plurality of cluster injection pipelines (106) are connected to the perforation assemblies (102) in the plurality of first cluster perforation groups (107) one by one. The fracturing fluid injection equipment (200) comprises an injection pump group (201), a total pressure monitoring device (202), a branch pipeline (205), a flow monitoring device (203) and a branch pressure monitoring device (204), the injection pump group (201) is used for pumping fracturing fluid, the total pressure monitoring device (202) is installed at the output end of the injection pump group (201) and is used for monitoring the total output pressure of the injection pump group (201), the number of the branch pipelines (205) is plural, the plurality of branch pipelines (205) are connected to the output end of the injection pump group (201) respectively through the plurality of cluster injection pipelines (106), the flow monitoring device (203) and the branch pressure monitoring device (204) are arranged on the plurality of branch pipelines (205) respectively, and are used for monitoring the branch flow and the branch pressure of the corresponding branch pipelines (205) respectively; the fracturing fluid injection equipment (200) further comprises a control device and a control valve (206), the control valve (206) is arranged on each of the plurality of branch pipelines (205), the control device is in communication connection with the control valve (206), the flow monitoring device (203) and the branch pressure monitoring device (204), and the control device is used for controlling the control valve (206) according to the detection data of the flow monitoring device (203) and the branch pressure monitoring device (204) on each of the branch pipelines (205). The perforating assembly (102) comprises a perforating joint (103), a perforating pipe (104), and a plurality of perforating modules (105) with different perforating modes, an inner side of the multi-cluster perforating wellbore (101) corresponds to each first sub-cluster perforating group (107) to select one of the perforating modules (105) for installation, the perforating module (105) is formed with a liquid distribution space (111) in communication with the sub-cluster liquid injection pipeline (106), and a second sub-cluster perforating group (108) is arranged on a circumferential side of the perforating module (105) and in communication with the liquid distribution space (111), second sub-cluster perforations in the second sub-cluster perforating group (108) are arranged in communication with part of the first sub-cluster perforations in the first sub-cluster perforating group (107) to form a perforating hole of the corresponding perforating mode, the perforating joint (103) is installed in the perforating hole, and the perforating pipe (104) is connected with the perforating joint (103) and extends out of the multi-cluster perforating wellbore (101); The perforating modes include spiral perforation, planar perforation, and limit perforation.

2. The competitive injection fracturing simulation system of claim 1, wherein, The perforating module (105) is formed with a threading channel (110) through which the sub-cluster liquid injection pipeline (106) passes, and the liquid distribution space (111) is arranged around the threading channel (110).

3. The competitive injection fracturing simulation system of claim 2, wherein, A guide (112) extending in a height direction is arranged on an inner wall of the multi-cluster perforating wellbore (101), and an outer side of the perforating module (105) is provided with a sliding member (113) movably installed on the guide (112), and a lower end of the guide (112) corresponds to the first sub-cluster perforating group (107).

4. The competitive injection fracturing simulation system according to any one of claims 1 to 3, characterized in that, The fracturing wellbore device (100) further comprises a perforating plugging member (114) for plugging the remaining perforating holes.

5. A method of simulating a competitive injection of a fracturing fluid in a fracturing process, characterized in that, The three-dimensional fracturing competitive injection simulation method adopts the three-dimensional fracturing competitive injection simulation system according to claim 4, and comprises a natural flow distribution experiment method, which comprises: In each of the plurality of first sub-cluster perforating groups (107), a perforating assembly (102) is installed with one of the perforating modes; The control valve (206) is controlled to be fully opened; First detection data of the flow monitoring device (203) and the differential pressure monitoring device (204) are received; A first rock sample crack form after a fracturing experiment by the three-dimensional fracturing competitive injection simulation system is obtained; Based on the first detection data and the first rock sample crack form, fracturing fluid natural distribution data under different perforating modes are determined.

6. The method of claim 5, wherein, The three-dimensional fracturing competitive injection simulation method further comprises a fixed flow distribution experiment method, which comprises: In each of the plurality of first sub-cluster perforating groups (107), a perforating assembly (102) is installed with one of the perforating modes; The opening degree of the control valve (206) is adjusted to keep the flow of each branch pipeline (205) unchanged; The receiving flow monitoring device (203) and the partial pressure monitoring device (204) obtain second detection data after multiple opening degree adjustments of the control valve (206); The stereoscopic fracturing competitive injection simulation system obtains second rock sample crack morphology after fracturing test under multiple opening degree adjustments of the control valve (206); The second detection data and the second rock sample crack morphology are used to determine the optimal fixed flow under different perforation modes.

7. The method of claim 6, wherein, The stereoscopic fracturing competitive injection simulation method further comprises a slot temporary plugging flow distribution experiment method, and the slot temporary plugging flow distribution experiment method comprises: In the multiple first sub-cluster perforation groups (107), a perforating assembly (102) is installed in each perforation group by using one of the perforation modes; The control valve (206) of one of the branch pipelines (205) is closed, and the opening degrees of the other two control valves (206) are adjusted; The receiving total pressure monitoring device (202) and the partial pressure monitoring device (204) obtain third detection data after multiple opening degree adjustments of the control valve (206); The stereoscopic fracturing competitive injection simulation system obtains third rock sample crack morphology after fracturing test under different control valve (206) closings; The third detection data and the third rock sample crack morphology are used to determine the optimal fixed pressure of slot temporary plugging under different perforation modes.

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