Parallel displacement device and experimental method for determining crude oil filling advantage channel

Abstract

This invention discloses a parallel displacement device and an experimental method for determining the dominant crude oil charging channel, relating to the field of oil and gas exploration technology. It includes a displacement pump, a data acquisition module, and multiple parallel clamping simulation systems. One end of each clamping simulation system is connected to the same displacement pump, and each clamping simulation system has a pressure sensor at both ends. Each pressure sensor is connected to the computer in the data acquisition module. Core samples with different permeabilities are placed inside each clamping simulation system. The displacement pump is used to charge water and oil into the clamping simulation system. Each clamping simulation system is independent and can be turned on or off individually. This invention can simulate the simultaneous injection of crude oil into core channels with different permeabilities under the same pressure system, visually representing the mutual influence of multiple core channels existing simultaneously, thereby achieving the effect of determining the dominant crude oil charging channel.

Description

Technical Field

[0001] This invention relates to the field of oil and gas exploration technology, specifically to a parallel displacement device and an experimental method for determining the dominant channel for crude oil charging. Background Technology

[0002] Currently, the world possesses abundant unconventional oil and gas resources, with production increasing significantly thanks to the development of horizontal well and volumetric fracturing technologies. Simultaneously, exploration and development practices in the unconventional oil and gas sector have also driven breakthroughs in classical oil and gas geological theories. Among these, theoretical research on crude oil charging has become a hot topic.

[0003] Previous research has shown that conventional and unconventional hydrocarbon systems mainly fall into several types, including pure oil (gas) without water, normal oil (gas) above water, inverted water above oil (gas), oil (gas) and water mixed in the same layer, isolated oil (gas) encased in water, and pure water without oil (gas). The distribution patterns of different types of oil, gas, and water are closely related to the dynamics, methods, and reservoir properties of oil and gas charging. From the perspective of the forces acting on oil and gas charging, the driving force for oil and gas migration is mainly buoyancy and hydrocarbon generation overpressure, while the resistance is mainly capillary pressure (affected by rock properties). When the driving force is greater than the resistance, oil and gas can charge the reservoir and become potential exploration targets; conversely, oil and gas cannot charge the reservoir.

[0004] The accumulation and formation of hydrocarbon reservoirs is essentially the process of displacement of pore fluids by hydrocarbons within the reservoir. Previous studies have extensively investigated this process through physical and numerical simulations. Physical simulations include segmented constant-pressure methods, nuclear magnetic resonance-displacement methods, and classical charging-displacement methods. Numerical simulations utilize pore-throat models or three-dimensional digital core models reconstructed from imaging scans to simulate the microscopic transport and accumulation of fluids.

[0005] In terms of physical simulation, all methods use a single core sample, simplifying the heterogeneity of cores with multiple physical properties existing simultaneously. Whether high-property-value cores are the dominant channels for crude oil charging over low-property-value cores, the magnitude of the property difference required for a dominant channel (how much permeability difference is needed to form a dominant migration channel), and how the existence of dominant channels affects the oil and gas charging behavior of non-dominant channels (differences in initiation and breakthrough pressures compared to single-core charging when both exist simultaneously) are all questions that cannot be verified through existing single-core physical simulation experiments. Summary of the Invention

[0006] The purpose of this invention is to provide a parallel displacement device and an experimental method for determining the dominant channel of crude oil injection, so as to solve the problems existing in the prior art. It simulates the simultaneous injection of crude oil into core channels with different permeability under the same pressure system, and characterizes the mutual influence of multiple core channels existing at the same time, thereby achieving the effect of determining the dominant channel of crude oil injection.

[0007] To achieve the above objectives, the present invention provides the following solution:

[0008] This invention provides a parallel displacement device, including a displacement pump, a data acquisition module, and multiple clamping simulation systems arranged in parallel. One end of each clamping simulation system is connected to the same displacement pump, and each clamping simulation system has a pressure sensor at both ends. Each pressure sensor is electrically connected to the data acquisition module. Each clamping simulation system is used to hold core samples with different permeabilities. The displacement pump is used to fill the clamping simulation system with water and oil. Each clamping simulation system is independent of each other and can be turned on or off individually.

[0009] Preferably, the clamping simulation system includes a core holder, a confining pressure system, a nitrogen cylinder, and a glass tube calibrator. The core holder is used to clamp the core sample. One end of the core holder is connected to the displacement pump via a filling pipeline, and a filling switch valve is provided on the filling pipeline. The other end of the core holder is connected to a back pressure valve via a discharge pipeline, and a discharge switch valve is provided on the discharge pipeline. The back pressure valve is also connected to the glass tube calibrator, and the back pressure valve is connected to the nitrogen cylinder via a back pressure pipeline, and a back pressure switch valve is provided on the back pressure pipeline. The confining pressure system is connected to the interior of the core holder, and a confining pressure switch valve is provided between the confining pressure system and the core holder.

[0010] Preferably, in the same clamping simulation system, one pressure sensor is located between the filling switch valve and the core holder, and the other pressure sensor is located between the discharge switch valve and the back pressure valve.

[0011] Preferably, the displacement pump is a micro-metering displacement pump.

[0012] Preferably, the data acquisition module is a computer acquisition system.

[0013] The present invention also provides an experimental method for determining the dominant crude oil charging channel of a parallel displacement device based on any one of the above technical solutions, comprising the following steps:

[0014] S1. Core sample selection and pretreatment: Based on the natural rock cores of clastic rocks from drilling in mature exploration areas, the physical properties are based on permeability. One sample is selected in each order of magnitude from 0.01mD to 100mD to prepare core columns. The core columns are pretreated by washing oil, drying, and wetting angle testing to ensure the water wetting conditions of the core. After that, porosity, permeability, and quality tests are conducted and recorded.

[0015] S2. The pretreated core samples from S1 are installed in the core holder of the parallel displacement device; first, the formation water with the same salinity as the original formation is saturated, and then a core simulation experiment of saturating formation water with crude oil is carried out; the charging pressure and the corresponding cumulative crude oil charging volume at any time are recorded by the computer acquisition system, and the corresponding displacement pump is turned off to stop charging when each core sample is confirmed to have reached oil saturation, and the charging situation of other core samples is observed. When the last core sample reaches oil saturation, the experiment is stopped.

[0016] S3. For each set of oil-saturated core sample clamping simulation systems that are shut down in S2, samples with crude oil filling volume will immediately appear in other clamping simulation systems from zero to one. The core sample preparation and pretreatment process in S1 needs to be repeated, and crude oil filling experiments should be conducted separately for comparative analysis.

[0017] S4. Organize, statistically analyze, and compile the experimental data from S2 and S3. Organize the charging pressure and corresponding cumulative charging oil volume detected during the charging process, and create a curve of changes in charging pressure and cumulative charging oil volume during the charging process. Based on this curve, determine the dominant channel for crude oil charging.

[0018] The present invention achieves the following technical effects compared to the prior art:

[0019] 1. This invention uses a parallel clamping simulation system to visualize the simultaneous injection of crude oil into core channels with different permeability under the same pressure system;

[0020] 2. This invention can characterize the mutual influence of multiple core channels existing simultaneously, and the simultaneous existence of multiple core channels is an objective fact of sedimentary strata, which is consistent with the objective heterogeneity of strata;

[0021] 3. This invention can effectively verify whether a dominant channel for crude oil charging exists when core channels with different permeabilities coexist, the influence of the magnitude of permeability difference on whether a dominant channel is generated, and how the existence of a dominant channel affects the oil and gas charging behavior of non-dominant channels. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the parallel displacement device in Embodiment 1;

[0024] Figure 2This is a flowchart of the experimental method for determining the dominant channel of crude oil charging in Example 2;

[0025] Figure 3 This is a graph showing the changes in charging pressure and cumulative charging oil volume during the charging process in Example 2;

[0026] In the diagram: 1-Displacement pump, 2-Injection switch valve, 3-Pressure sensor, 4-Core holder, 5-Containing pressure system, 6-Containing pressure switch valve, 7-Discharge switch valve, 8-Glass tube gauge, 9-Back pressure valve, 10-Nitrogen cylinder, 11-Back pressure switch valve, 12-Data acquisition module. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] The purpose of this invention is to provide an experimental method for determining the dominant channel of crude oil injection using a parallel displacement device, in order to solve the technical problem that existing single core physical simulation experiments cannot simulate the intuitive situation of simultaneous injection of crude oil into core channels with different permeabilities under the same pressure system, and cannot characterize the mutual influence of multiple core channels existing at the same time.

[0029] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] Example 1

[0031] like Figure 1 As shown, this embodiment provides a parallel displacement device, including a displacement pump 1, a data acquisition module 12, and multiple clamping simulation systems arranged in parallel. One end of each clamping simulation system is connected to the same displacement pump 1, and each clamping simulation system has a pressure sensor 3 at both ends. Each pressure sensor 3 is electrically connected to the data acquisition module 12. Each clamping simulation system is used to place core samples with different permeabilities. Through the parallel clamping simulation systems, the simultaneous injection of crude oil into core channels with different permeabilities under the same pressure system can be visualized. The displacement pump 1 is used to fill the clamping simulation system with water and oil. Each clamping simulation system is independent of each other and can be turned on or off individually.

[0032] Specifically, the clamping simulation system includes a core holder 4, a confining pressure system 5, a nitrogen cylinder 10, and a glass tube scale 8. The core holder 4 is used to clamp the core sample. One end of the core holder 4 is connected to the displacement pump 1 through a filling pipeline, and the filling pipeline is equipped with a filling switch valve 2, which can realize the filling of water or oil into the core sample or stop the filling. The other end of the core holder 4 is connected to a back pressure valve 9 through a discharge pipeline, and the discharge pipeline is equipped with a discharge switch valve 7. The back pressure valve 9 is also connected to the glass tube scale 8 to adjust the glass tube scale. A pressure gauge 8 is placed at the outlet end of the core sample to measure the volume of water displaced by the injected crude oil. It also measures the amount of excess oil injected after the core sample is saturated with oil; the difference between this and the injected amount is the amount of saturated crude oil injected into the core sample. A backpressure valve 9 is connected to a nitrogen cylinder 10 via a backpressure pipeline. The backpressure valve 9 controls the pressure and flow rate of the fluid passing through. A backpressure switch valve 11 is installed on the backpressure pipeline. The confining pressure system 5 is internally connected to the core holder 4, and a confining pressure switch valve 6 is installed between the confining pressure system 5 and the core holder 4. The installation of these switches allows for checking the airtightness of the entire apparatus before the experiment begins, and for controlling water filling, oil filling, and confining pressure application as needed during the experiment.

[0033] In the same clamping simulation system, one pressure sensor 3 is located between the filling switch valve 2 and the core clamp 4, and another pressure sensor 3 is located between the discharge switch valve 7 and the back pressure valve 9. Thus, by setting each pressure sensor 3, real-time monitoring of the inlet and outlet pressures of the core clamp 4 can be achieved.

[0034] Displacement pump 1 is a micro-metering displacement pump.

[0035] Data acquisition module 12 is a computer-based data acquisition system.

[0036] Example 2

[0037] like Figures 2-3 As shown, this embodiment provides an experimental method for determining the dominant crude oil charging channel based on the parallel displacement device in Embodiment 1. Parallel displacement experiments are conducted using an improved parallel displacement device, selecting typical core samples with different permeabilities and setting them in parallel. By adjusting the charging pressure, the differences in crude oil charging under conditions where multiple physical property core samples coexist are characterized, forming a method for verifying the crude oil charging mode. Specifically, the method includes the following steps:

[0038] S1. Core sample selection and pretreatment, specifically including:

[0039] S1a. Based on core samples from well drilling in mature oilfield exploration areas, with basic physical property data (porosity and permeability), using permeability as a parameter, sample points with values ​​in each range are selected to prepare core columns. The core column dimensions are: length 5cm and diameter 2.5cm. Those skilled in the art can make adaptive changes to the core column dimensions according to actual needs.

[0040] S1b. Test and record the original oil saturation of the core sample;

[0041] S1c. Wash the core sample with oil, dry it, and then test the porosity, permeability, and quality of the dried sample. During the washing process, surfactants can be added to eliminate the oil wettability of the core sample and wettability tests are performed to ensure that the core sample is only wetted by water, so as to simulate the general water wettability conditions of the real formation before it is filled with crude oil.

[0042] S2. Simulation of crude oil-saturated formation water cores, specifically including:

[0043] S2a. Assemble the parallel displacement device in Example 1. The number of core holders 4 is preferably 5. Place core samples with different permeabilities into the 5 core holders 4 respectively to simulate the difference in the dominant transport channels of core samples under different physical property conditions.

[0044] S2b. Sample Saturation Simulation of Formation Water Treatment: After the core sample is installed in the core holder 4, the air tightness of the parallel displacement device is tested. The confining pressure is adjusted by the confining pressure pump in the confining pressure system 5 to always be higher than the driving pressure by 2MPa. The air in the core sample is displaced by the high-pressure water injection system in the displacement pump 1. At this time, the oil injection system in the displacement pump 1 is in the closed state until no gas is discharged from the outlet of the core holder 4. The core is considered to be saturated with formation water. The specific observation method for the gas discharge at the outlet of the core holder 4 is as follows: when the drainage volume and the filling water volume observed in the glass tube scale 8 are equal, it can be considered that the gas has been removed; or water is injected into the glass tube scale 8 in advance. If the gas is removed, it can push the water out of the glass tube scale 8. The formation water ratio is based on the actual formation water salinity of the oilfield. The water type is NaHCO3 and the density is 1.02g / mL.

[0045] S2c. Preparation of crude oil: The crude oil has a viscosity of 44 mPa·s and a density of 0.75 g / mL;

[0046] S2d. Steady-state simulation of crude oil charging: The high-pressure water injection system is closed, the oil injection system is opened, and crude oil is injected with an initial driving pressure of 1 MPa. The oil and water flow rates at the outlets of the five core holders 4 are monitored by a glass tube scale 8 at a time unit of 1 hour. When the pressure difference between the two ends of the core holder 4 is stable, the driving pressure is increased in units of 1 MPa, and the steady-state simulation of crude oil charging process is repeated.

[0047] S2e. For each clamping simulation system, when crude oil is first injected into the clamping simulation system (cumulative injection volume > 0 ml), the driving pressure at that moment is recorded as the critical start-up pressure; if the driving pressure is continuously increased, but the cumulative injection volume at the outlet of the core clamp 4 does not increase, the injection system corresponding to the core clamp 4 is shut down, and the injection pressure corresponding to the maximum is recorded as the critical breakthrough pressure.

[0048] S2f. Continue to increase the driving pressure, observe and record the charging pressure and cumulative charging oil volume of the charging system corresponding to each core holder 4, record the critical start pressure and critical breakthrough pressure, and shut down the corresponding charging system when the maximum cumulative charging oil volume is reached, until all charging systems are shut down and the experiment is stopped.

[0049] S3. Control group: Steady-state filling simulation experiments were conducted using the original method of single core holder 4-stage filling simulation, and the results were recorded. Specifically, this included:

[0050] S3a. During the parallel charging process, each time the clamping simulation system of a set of high-permeability core samples is closed, the sample record of crude oil charging immediately appears in the clamping simulation system of the secondary permeability core samples.

[0051] S3b. After the parallel experiment is completed, the secondary permeability core sample in S3a needs to be repeated in S1 to prepare water-wetting and saturated water test samples again.

[0052] S3c. A steady-state filling simulation experiment using a single system was conducted, and the parameters were recorded as a control group.

[0053] S4. Experimental data processing, calculation, statistics, and analysis, specifically including:

[0054] S41. Compile the charging pressure and corresponding cumulative charging oil volume detected during the charging process;

[0055] S42. Create a graph showing the changes in charging pressure and cumulative charging volume during the charging process;

[0056] S43. Based on the above curve, determine the dominant channel for crude oil charging. The determination method is as follows:

[0057] Section A: Injection pressure is 1MPa-3MPa, with an initial pressure of 1MPa. The first core sample (i.e., a core sample with a permeability of 100mD) and the second core sample (i.e., a core sample with a permeability of 10mD) generate cumulative injection oil at the start of the test. The third core sample (i.e., a core sample with a permeability of 1mD), the fourth core sample (i.e., a core sample with a permeability of 0.1mD), and the fifth core sample (i.e., a core sample with a permeability of 0.01mD) do not generate injection oil. Increasing the injection pressure to 2MPa... MPa: The cumulative oil charge of the first core sample remained unchanged compared to the last moment of the 1MPa stage; the second core sample was in the stage of increasing cumulative oil charge; the third, fourth, and fifth core samples did not generate any oil charge. When the charging pressure was increased to 3MPa, the cumulative oil charge of the first core sample remained unchanged compared to the last moment of the 1MPa stage; the cumulative oil charge of the second core sample remained unchanged compared to the last moment of the 2MPa stage; the third, fourth, and fifth core samples did not generate any oil charge.

[0058] Analysis in section A: The first and second core samples have high permeability, and low charging pressure is sufficient to overcome capillary resistance and initiate crude oil charging. The first core sample has higher permeability than the second core sample, and its breakthrough charging pressure of 1 MPa for oil saturation is lower than that of the second core sample of 2 MPa. After reaching the breakthrough pressure, the cumulative amount of oil charged in the first and second core samples will not continue to increase, proving that the oil content is saturated. The third, fourth, and fifth core samples do not generate any charging oil, possibly because 3 MPa is still not the critical charging pressure (starting charging pressure) required by the samples, or because the first and second core samples are the dominant channels for crude oil charging compared to the third, fourth, and fifth core samples. Analysis in section C suggests the former reason.

[0059] Section B: The charging pressure is 3MPa-8MPa. The charging system of the first core sample is shut down. The pressure is increased by 1MPa and observed for 5 hours until it reaches 8MPa (5MPa pressure difference). The cumulative amount of oil charged in the second core sample is unchanged relative to the last moment of the 2MPa stage. The third, fourth and fifth core samples do not generate any amount of oil charged.

[0060] Analysis of Section B: Closing the charging system corresponding to the first core sample does not affect the maximum cumulative charging oil volume of the second core sample. Even if crude oil does not flow through the first core sample, it still cannot change the maximum cumulative charging oil volume of the second core sample, proving that the existence of the maximum oil saturation of the inherent core sample and the existence of the dominant crude oil migration channel in space are irrelevant. Closing the charging system corresponding to the first core sample does not affect the charging oil volume of the third, fourth, and fifth core samples. The possible reason is that the sample pressure of 8 MPa has not yet reached the critical charging pressure (starting charging pressure) required by the core sample, or the second core sample can still serve as a dominant crude oil charging channel compared to the third, fourth, and fifth core samples. Analysis of Section C suggests the latter reason.

[0061] Section C: The injection pressure is 8MPa-20MPa. At 8MPa, the injection system corresponding to the second core sample is shut off, and the third core sample immediately generates injection oil, while the fourth and fifth core samples do not. From 8MPa to 12MPa, the cumulative injection oil volume of the third core sample increases rapidly. At 12MPa, the fourth core sample generates injection oil, while the fifth core sample does not. From 12MPa to 18MPa, the cumulative injection oil volume of the third core sample reaches its maximum and does not increase further after 14MPa. The cumulative injection oil volume of the fourth core sample increases rapidly, and at 18MPa, the fifth core sample generates injection oil.

[0062] Section C Analysis: Through the control group experiment, under the condition of single non-parallel charging, the third core sample at 5MPa produced charging oil, proving that the starting charging pressure of the third core sample is 5MPa. However, when the second core sample was connected in parallel, the third core sample at 5MPa did not produce charging oil, while the third core sample at 8MPa immediately produced charging oil because the dominant channel of the corresponding charging system of the second core sample was closed. The fourth and fifth core samples at 12MPa and 18MPa produced charging oil because the starting pressure conditions of the fourth and fifth core samples were met. At the same time, it can be proved that the third core sample, compared with sample ④ and the fifth core sample, cannot be regarded as the absolute dominant channel.

[0063] Section D: The charging pressure is 20MPa-24MPa. At 20MPa, the charging system corresponding to the third core sample is shut down. At 20MPa-22MPa, the cumulative charging oil volume curves of the fourth and fifth core samples first increase in slope, and then increase in a stepwise manner. At 22MPa, the cumulative charging oil volume of the fourth core sample reaches the maximum, and the cumulative charging oil volume of the fifth core sample continues to increase.

[0064] Segment D analysis: After shutting down the charging system corresponding to the third core sample, the amount of oil entering the fourth and fifth core samples increased rapidly, leading to an increase in slope (charging flow rate). As the pressure increased, the oil broke through smaller pore channels, showing a step-like growth. This proves that the fourth and fifth core samples have low permeability and non-uniform pore channel radii, resulting in non-homogeneous capillary resistance, corresponding to multiple critical charging pressures.

[0065] Section E: The charging pressure is 24MPa-25MPa. At 24MPa, the charging system corresponding to the fourth core sample is shut off. The cumulative charging oil volume curve of the fifth core sample first increases in slope, then increases in a stepwise manner, and the charging oil volume reaches its maximum at 25MPa.

[0066] Analysis of Section E: After shutting down the charging system corresponding to the fourth core sample, the amount of oil entering the fifth core sample increased rapidly, resulting in an increase in slope (charging flow rate). As the pressure increased, it broke through smaller pore channels, showing a step-like growth, which proved that the fifth core sample had low permeability and uneven pore channel radius, resulting in non-homogeneous capillary resistance, corresponding to multiple critical charging pressures (similar to Section D).

[0067] Analysis conclusion: The existence of a critical initiation pressure enables crude oil to be charged into core samples with a certain permeability. Whether it can be truly charged depends on the spatial configuration of the various types of channels. The first and second core samples are the dominant transport channels relative to the third, fourth, and fifth core samples. If the first and second core samples are present, the third, fourth, and fifth core samples will not be charged with crude oil regardless of whether the critical initiation pressure is reached.

[0068] Note: Experimental time is a relative concept, and experimental data are related to the porosity, permeability, pore structure, mineral composition, and diagenetic type of the actual application sample section.

[0069] This specification uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. An experimental method for determining the filling of dominant channels in crude oil based on a parallel displacement device, characterized by: The parallel displacement device includes a displacement pump, a data acquisition module, and multiple clamping simulation systems arranged in parallel. One end of each clamping simulation system is connected to the same displacement pump, and each clamping simulation system has a pressure sensor at both ends. Each pressure sensor is electrically connected to the data acquisition module. Each clamping simulation system is used to hold core samples with different permeabilities. The displacement pump is used to fill the clamping simulation system with water and oil. Each clamping simulation system is independent of each other and can be turned on or off individually. The experimental method for determining the dominant channel of crude oil charging includes the following steps: S1. Core sample selection and pretreatment: Based on the natural rock cores of clastic rocks from drilling in mature exploration areas, the physical properties are based on permeability. One sample is selected in each order of magnitude from 0.01mD to 100mD to prepare core columns. The core columns are pretreated by washing oil, drying, and wetting angle testing to ensure the water wetting conditions of the core. After that, porosity, permeability, and quality tests are conducted and recorded. S2. The pretreated core samples from S1 are installed in the core holder of the parallel displacement device; first, the formation water with the same salinity as the original formation is saturated, and then a core simulation experiment of saturating formation water with crude oil is carried out; the charging pressure and the corresponding cumulative crude oil charging volume at any time are recorded by the computer acquisition system, and the corresponding displacement pump is turned off to stop charging when each core sample is confirmed to have reached oil saturation, and the charging situation of other core samples is observed. When the last core sample reaches oil saturation, the experiment is stopped. S3. For each set of oil-saturated core sample clamping simulation systems that are shut down in S2, samples with crude oil filling volume will immediately appear in other clamping simulation systems from zero to one. The core sample preparation and pretreatment process in S1 needs to be repeated, and crude oil filling experiments should be conducted separately for comparative analysis. S4. Organize, statistically analyze, and compile the experimental data from S2 and S3. Organize the charging pressure and corresponding cumulative charging oil volume detected during the charging process, and create a curve of changes in charging pressure and cumulative charging oil volume during the charging process. Based on this curve, determine the dominant channel for crude oil charging.

2. The experimental method for determining the filling preferential channel of crude oil based on the parallel displacement device according to claim 1, characterized in that: The clamping simulation system includes a core holder, a confining pressure system, a nitrogen cylinder, and a glass tube calibrator. The core holder is used to clamp the core sample. One end of the core holder is connected to the displacement pump via a filling pipeline, and the filling pipeline is equipped with a filling switch valve. The other end of the core holder is connected to a back pressure valve via a discharge pipeline, and the discharge pipeline is equipped with a discharge switch valve. The back pressure valve is also connected to the glass tube calibrator, and the back pressure valve is connected to the nitrogen cylinder via a back pressure pipeline, and the back pressure pipeline is equipped with a back pressure switch valve. The confining pressure system is connected to the interior of the core holder, and a confining pressure switch valve is provided between the confining pressure system and the core holder.

3. The experimental method for determining the filling preferential channel of crude oil based on the parallel displacement device according to claim 2, characterized in that: In the same clamping simulation system, one pressure sensor is located between the filling switch valve and the core holder, and the other pressure sensor is located between the discharge switch valve and the back pressure valve.

4. The experimental method for determining the filling preferential channel of crude oil based on the parallel displacement device according to claim 1, characterized in that: The displacement pump is a micro-displacement displacement pump.

5. The experimental method for determining the dominant crude oil charging channel based on a parallel displacement device according to claim 1, characterized in that: The data acquisition module is a computer acquisition system.

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