Experimental design method for measuring relative permeability hysteresis parameters of high-temperature and high-pressure oil-containing core by gas-water alternation

Abstract

The invention relates to the field of petroleum and natural gas development, in particular to an experimental design method for gas-water alternate measurement of relative permeability hysteresis parameters of a high-temperature and high-pressure oil-bearing core. The invention aims to directly calculate the hysteresis parameters such as gas-water phase permeability, gas-oil phase permeability, oil-water phase permeability and the like required by phase permeability hysteresis numerical simulation from a phase permeability experiment result through a method for calculating the hysteresis parameters in a phase permeability hysteresis model through a pertinently designed phase permeability experiment, so that the parameter acquisition accuracy is improved; a large number of fitting adjustment processes of an existing method are avoided, a rapid research tool is provided for research on evaluation of CO2 burying, underground gas storage construction, gas-water alternation recovery ratio improvement, hydrogen storage and the like which are affected by relative permeability lag, and the numerical simulation workload is reduced.

Description

Technical Field

[0001] The invention relates to the field of oil and gas development, in particular to a method for determining a hysteresis parameter in a phase permeability hysteresis model through a phase permeability experiment. Technical Background

[0002] The phase permeability hysteresis effect has a significant impact on applications such as gas injection to enhance oil recovery, construction of gas storage, and CO2 storage. The method for determining the phase permeability hysteresis parameters in existing numerical modeling studies is mainly based on fitting to experiments. For example, "Analysis method, equipment and storage medium for injection and production of fracture-cavity gas storage" (CN117993228A) proposes to consider the phase permeability hysteresis effect in the numerical simulation study of gas storage. It only calculates the gas storage in the existing phase permeability hysteresis model, and does not take into account the representativeness of the phase permeability hysteresis parameters input in the model and their acquisition methods.

[0003] At present, the experimental research on gas-water alternation phase permeability has become mature. There are many two-phase and three-phase phase permeability hysteresis models at home and abroad, and some models have been applied to commercial simulators. However, the acquisition of key parameters of the phase permeability hysteresis model is based on numerical simulation, and there is no simple calculation method directly based on experimental results. Therefore, the present invention specifically designs a multi-cycle gas-water mutual drive experiment of oil-bearing cores under high temperature and high pressure conditions, establishes a calculation method for the input parameters of the three-phase phase permeability hysteresis model in the process of gas-water alternation, improves the accuracy of parameter acquisition, and reduces the workload of numerical simulation. Summary of the invention

[0004] The present invention aims to provide a method for calculating the hysteresis parameters in a phase permeability hysteresis model through a phase permeability experiment designed in a targeted manner, and directly calculates the hysteresis parameters required for the numerical simulation of phase permeability hysteresis from the phase permeability experiment results, which can improve the accuracy of parameter acquisition and avoid a large number of fitting and adjustment processes in existing methods. It provides a rapid research tool for evaluating research involving the effects of phase permeability hysteresis, such as CO2 storage, underground gas storage construction, gas-water alternation to enhance recovery, hydrogen storage, etc., and reduces the workload of numerical simulation.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] An experimental design method for measuring phase permeability hysteresis parameters of high-temperature and high-pressure oil-bearing core gas-water alternation, comprising the following steps:

[0007] Step S1: Conduct high temperature and high pressure multi-cycle CO2-water alternating mutual drive experiments using actual reservoir cores and measure core relative permeability data;

[0008] Step S2: determining a calculation method for hysteresis parameters of the phase permeability hysteresis model, wherein the calculation is divided into non-wetting phase permeability, wetting phase permeability and intermediate wetting phase permeability;

[0009] Step S3: Select data based on the experimentally measured multi-cycle phase permeability curve data to calculate the hysteresis model hysteresis parameters a and α:

[0010] Step S4: completing crude oil PVT fitting based on crude oil and degassing composition data combined with experimental data such as saturation pressure, gas-oil ratio, MMP, etc.;

[0011] Step S5: Establish a core model in the simulator according to the experimental core physical data, and input hysteresis parameters to start the simulator hysteresis effect function;

[0012] Step S6: Output the model recovery factor comparison experiment to verify the fitting effect.

[0013] As a preferred embodiment of the present invention, in step S1, the gas-water two-phase permeability curve, the water-oil three-phase permeability curve, and the gas-oil three-phase permeability curve are measured respectively, wherein the gas-water two-phase permeability experiment is directly carried out after the core is saturated with water for displacement measurement, and the oil-containing three-phase permeability experiment is to use active oil displacement to establish bound water after the core is saturated with water, and then gas drive or water drive is carried out to establish residual oil. Considering the influence of gas drive start and water drive start on the permeability hysteresis phenomenon, if gas drive is used to start to establish residual oil, a gas-water alternation experiment starting with six cycles of water drive is subsequently carried out, and vice versa; the gas-water two-phase permeability curve and the gas-oil, water-oil three-phase permeability curve of the reservoir core required for subsequent calculations are obtained through three types of permeability experiments, as well as their multi-cycle curve changes.

[0014] As a preferred embodiment of the present invention, the calculation of the non-wetting phase permeability in step S2 includes the following sub-steps:

[0015] (a) Calculation of gas saturation scanning curve during displacement process

[0016]

[0017] Where: n---represents the number of cycles; take n=2 as an example, ---Relative permeability at Sg in the second drainage curve; ---Relative permeability at the first drainage Sg; --- Relative permeability of gas saturation at the starting point of the second drainage curve in the first drainage curve; ---Water saturation at the end of the second drainage; ---Water saturation at the starting point of the second drainage curve; S g --- Gas saturation in the second drainage curve; ---Gas saturation at the starting point of the second drainage curve; ---Relative permeability at gas saturation at the starting point of the second drainage curve in the first imbibition curve;

[0018] (b) Calculation of gas saturation scanning curve during imbibition process

[0019]

[0020] Where:

[0021] in: ---Gas saturation at the time of the nth cycle transition; (S g ) n ---Gas saturation in the nth cycle; ---nth- 1 Gas saturation at the end of the cycle; (S gi ) n --- Initial gas saturation of the nth cycle; ---Residual gas saturation at the time of the nth cycle conversion; (S gr ) n ---Residual gas saturation in the nth cycle.

[0022] As a preferred embodiment of the present invention, the calculation of the wetting phase permeability in step S2 includes the following sub-steps:

[0023] (a) Calculation of water saturation scanning curve during imbibition process

[0024]

[0025] in: ---The first water phase relative permeability input; --- Second water phase relative permeability; --- Initial gas saturation; (S g ) max --- Maximum gas saturation;

[0026] (b) Calculation of water saturation scanning curve during displacement process

[0027] 1) If

[0028]

[0029] 2) If

[0030]

[0031] 3) If the gas saturation is constant

[0032]

[0033] in: ---Water phases infiltrate at the end of final imbibition.

[0034] As a preferred embodiment of the present invention, the calculation of the intermediate wetting phase permeability in step S2 includes the following sub-steps:

[0035] In the phase permeability hysteresis model, the oil phase relative permeability is a function of the oil saturation and the historical saturation, from which the intermediate wetting relative permeability can be calculated;

[0036]

[0037] Among them: Sg t ----The trapped gas saturation after water flooding is completed;

[0038] Calculate the captured gas Land coefficient:

[0039]

[0040] Where: S gi ---Initial gas saturation, S gr --- Captured gas saturation;

[0041] The hysteresis parameters input in the simulator are "a" and "α". After the hysteresis function is turned on in the simulator, the Land coefficient is input to represent the change of the captured gas saturation in the multi-cycle experiment. The hysteresis parameters are calculated by formula (1) and formula (11), and the captured gas coefficient is calculated by formula (12).

[0042] in:

[0043] “a” represents the reduction degree of residual oil saturation to oil phase relative permeability in the WAG simulation process;

[0044] “α” is used to calculate the input parameter of the scanning curve during displacement (i.e., increasing gas saturation), representing the reduction degree of relative permeability with the change of gas saturation;

[0045] “C” represents the coefficient of variation of captured gas saturation in different periods.

[0046] As a preferred solution of the present invention, step S3 further includes the following sub-steps:

[0047] Step S31: Calculation of hysteresis parameter "a": According to the experimental results, the residual oil saturation at the start of gas drive and water drive in each of the six cycles and the trapped gas saturation at the end of water drive are respectively calculated and substituted into formula (11) to calculate the hysteresis parameter "a";

[0048] Step 32: Calculation of hysteresis parameter "α": To calculate the parameter "α", the phase permeability data of adjacent cycles in the six-cycle experiment are required. The other parameters of formula (1) are substituted and calculated to obtain the hysteresis parameter "α" in the drainage curve and the imbibition curve of the adjacent cycles.

[0049] Step 33: Calculation of the trapped gas Land coefficient "C": Based on the saturation data of the experimental results, the initial gas saturation at the start of gas drive and water drive in each of the six cycles and the trapped gas saturation after the displacement are calculated, and substituted into formula (12) to calculate the trapped gas coefficient "C".

[0050] As a preferred embodiment of the present invention, in step S4, the content of each component in the crude oil should be determined first, and the composition of each component in the crude oil and natural gas should be obtained by chromatographic analysis of the dead oil. The component data should be input into the simulator PVT module, and the well flow composition should be divided into pseudo-components. Then, according to the crude oil analysis experimental data, the key parameters of crude oil properties such as MMP (minimum miscibility pressure), gas-oil ratio, saturation pressure, viscosity, volume coefficient and relative volume should be fitted, and it should be ensured that the error between the experimental value and the fitting value is within 5%.

[0051] As a preferred embodiment of the present invention, in step S5, a core model should be established in the simulator at a 1:1 ratio based on the experimentally measured core physical data, and the experimentally measured gas-water phase permeability curve, gas-oil phase permeability curve, oil-water phase permeability curve, porosity, permeability and other data should be input. After the PVT-fitted fluid is imported, the hysteresis parameters "a" and "α" calculated based on the experimental data should be input to start the model phase permeability hysteresis simulation function, and the same experimental conditions and injection parameters should be established in the model for simulation.

[0052] As a preferred embodiment of the present invention, step S6 also includes: outputting the model recovery result after completing the model operation, and comparing it with the experimental recovery result to check the fitting effect. If the error between the final recovery rate of the model and the experimental recovery rate is not large, it means that the lag parameters calculated by the experimental data are effective and can be applied to subsequent mechanism model or geological model research. If the error between the model recovery rate and the experimental recovery rate is large, the lag parameters need to be adjusted.

[0053] Compared with the prior art, the present invention has the following beneficial effects:

[0054] (1) The present invention designs a multi-cycle gas-water relative permeability experiment that can directly measure the relative permeability hysteresis model parameters;

[0055] (2) Through the designed targeted experiments, the input parameters of the phase permeability hysteresis model are directly calculated, including the first period, gas-water phase permeability, gas-oil phase permeability, oil-water phase permeability, a, α, and C;

[0056] (3) The phase permeability curve obtained from the experiment is the direct input parameter of the model. The model parameters calculated based on the experimental phase permeability can be directly input into the model for verification and can be directly used for subsequent simulations or as initial values ​​for fitting adjustments, which improves the accuracy of parameter acquisition and avoids the large amount of fitting and adjustment processes in existing methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 Flow chart of phase permeability hysteresis experiment of high temperature and high pressure CO2-water alternating flooding;

[0058] Figure 2 Flowchart of implementation method;

[0059] Figure 3 Experimental results: Two-phase permeability curve;

[0060] Figure 4 Experimental results: three-phase permeability curve;

[0061] Figure 5 Experimental results: Three-phase permeability saturation path diagram;

[0062] Figure 6 Calculation result diagram of hysteresis parameter a;

[0063] Figure 7 The specific position of the calculation parameter of the gas drive initial hysteresis parameter α in the experimental phase permeability curve;

[0064] Figure 8 The specific position of the water flooding initial hysteresis parameter α in the experimental phase permeability curve;

[0065] Fig. 9 Calculation results of captured gas Land coefficient C;

[0066] Fig.10 A core model map with a grid number of 29×3×3 was established;

[0067] Fig.11 The model recovery factor and experimental recovery factor fitting results diagram; DETAILED DESCRIPTION

[0068] In order to more clearly describe the invention purpose, technical scheme and technical effect advantages in the specific implementation case of the present invention, the scheme in the specific embodiment will be described in detail in combination with the drawings of the specification of the present invention. The specific technical scheme involved in the following specific embodiments is only for a clear and complete description of the innovative technical scheme of the present invention. It is only a part of the specific implementation scheme that can be adopted by the present invention, not all embodiments, and should not be understood as a limitation on the innovative scheme of the present invention. Any scheme adopting the same inventive concept of the present invention should be included in the protection scope of the present invention.

[0069] Secondly, the description of the drawings in the specific embodiments of the present invention is only for the convenience of technical personnel to understand the solution of the present invention. The partial details in the drawings are for the convenience of clearly presenting the technical solution. It should not be considered that all technical features in the drawings must be included in the specific implementation cases, and the detailed features in the drawings should not be identified as additional limitations on the innovative technical solution of the present invention. The components in the various embodiments described and shown in the drawings can be combined and arranged according to different configurations, and these changes in combination and arrangement should be identified as part of the entire embodiment of the innovative solution of the present invention and included in the scope of protection of the present invention.

[0070] In summary, the schemes or descriptions presented in the specific embodiments and drawings of the present invention are not intended to limit the scope of protection claimed, but are merely selected embodiments / cases to help technicians understand the relevant innovative solutions. Based on these embodiments, all other equivalent or parallel embodiments obtained by those skilled in the art without creative work are within the scope of protection claimed by the present invention.

[0071] In addition, in the description of the embodiments of the present invention, "several", "plurality" and "a number" represent at least 2. It can be 3, 4, 5, 6, 7, 8, 9, etc., or even more than 9.

[0072] An experimental design method for measuring phase permeability hysteresis parameters of high-temperature and high-pressure oil-bearing core gas-water alternation, comprising the following steps:

[0073] (1) Conduct high-temperature and high-pressure multi-cycle CO2-water alternating flooding experiments using actual reservoir cores and measure core relative permeability data;

[0074] The implementation process is as follows Figure 1 As shown, before the experiment, the size, porosity, permeability, bound water saturation and other data of the experimental core were measured to provide accurate data for establishing the core model. The specific parameters of the experimental core are shown in Table 1 below:

[0075] Table 1

[0076] Length, cm Average diameter, cm Pore ​​volume, cm3 Core volume, cm3 Permeability, md Immune water saturation Average porosity 28.87 2.49 31.96 140.88 215.69 0.35 0.23

[0077] The phase permeability curve was measured by mutual drive experiment, mainly referring to the national standard: "GB / T 28912-2012 Method for Determining Relative Permeability of Two-Phase Fluids in Rocks" and the invention patent "Method for Determining Gas-Water Phase Permeability Curves at High Temperature and High Pressure in Formations" (CN103645126B, 2015-09-30), and multi-cycle gas-water mutual drive oil-bearing core three-phase fluid relative permeability and gas-water two-phase relative permeability tests were carried out. The two-phase experiment and the three-phase experiment were measured for six cycles respectively. Considering the influence of the start of gas drive and the start of water drive on the oil-bearing core in the three-phase experiment, the three-phase phase permeability experiment was divided into two categories, namely gas drive start and water drive start. The specific experimental process is as follows Figure 2 shown.

[0078] The experimental steps in this embodiment are as follows:

[0079] (a) Configure balance gas and balance water

[0080] ①Prepare formation water based on the formation water analysis data of the actual oil reservoir.

[0081] ② Select pure CO2, fill the water sample intermediate container and the gas sample intermediate container with the prepared formation water and high-pressure CO2 under the experimental pressure respectively at the experimental temperature and pressure, fill the sample preparation device with 50% volume of formation water, and inject 50% CO2 under the experimental pressure, shake and stir for 8 to 10 hours, and maintain excess CO2 dissolved in the water at the experimental temperature and pressure.

[0082] ③ Refer to the standard SY / T5543-2002 "Analysis method of fluid physical properties in condensate gas reservoirs", and conduct single stripping test on the balance gas and balance formation water. Transfer the balance gas sample on the upper part of the sample distributor and the balance water sample on the lower part to the PVT instrument to measure the balance gas B g The volume coefficient B of the equilibrium formation water w and gas-water ratio.

[0083] The final configuration of the balance gas and balance water volume coefficients are shown in Table 2 below:

[0084] Table 2

[0085]

[0086] (b) Saturated water: Dry and weigh the core, evacuate it, saturate the core at room temperature and 6000psi, take it out after 24-36 hours and weigh it again to determine the saturated water content of the core, put it into the core holder, and then put it into the high-pressure long core holder, close the outlet and pressurize it to the experimental pressure of 32.67MPa with formation water, and heat it to 64℃ at the same time. During the pressurization process, keep the confining pressure 3-4MPa higher than the inlet pressure, and wait until the temperature and pressure are stable. At the experimental temperature and pressure, perform constant pressure balance water to replace the formation water until it is stable to complete the core saturation water.

[0087] Two-phase experiment: After the experimental core is saturated with water, gas drive is started directly to measure the gas-water two-phase permeability.

[0088] Three-phase experiment: After the experimental core is saturated with water, the prepared live oil is used to drive oil into water to establish bound water, and then constant pressure balanced water drive oil is used to establish residual oil (gas drive oil is used to establish residual oil at the beginning of water drive), and finally the gas-oil and water-oil three-phase permeability is measured.

[0089] (c) Gas-driven water (the measurement process of two-phase permeability is consistent with that of three-phase permeability): The gas-driven water permeability test is carried out using a gas-driven constant pressure method. The experimental process and experimental records are consistent with the standards, including time, cumulative water production (including condensed water), cumulative gas production, confining pressure, inlet and outlet pressures. The water is driven until no water is produced, and then the gas output per unit time is recorded to determine the gas permeability under bound water conditions.

[0090] (d) Water-driven gas (the measurement process of two-phase permeability is consistent with that of three-phase permeability): The water-driven gas permeability test is carried out using a water-driven constant pressure method. The experimental process and experimental records are consistent with the standards, including time, cumulative water production (including condensed water), cumulative gas production, confining pressure, inlet and outlet pressures, until no gas is released after water drive. Then the water output per unit time is recorded to determine the water permeability under gas capture conditions.

[0091] Final experimental results Figure 3 , 4 As shown in the figure, they are the six-cycle two-phase permeability curve and three-phase permeability curve at the beginning of gas drive and water drive, respectively. Figure 5 It represents the saturation path diagram at the beginning of gas drive and water drive in the three-phase permeability experiment.

[0092] (2) According to the experimental multi-cycle phase permeability curve data, the hysteresis parameters a and α in the phase permeability hysteresis model are calculated respectively;

[0093] (a) Calculation of hysteresis parameter "a":

[0094] According to the experimental relative permeability data, the residual oil saturation of each cycle at the start of gas drive and water drive in six cycles and the trapped gas saturation at the end of water drive were respectively substituted into formula (11) to fit the slope to obtain the hysteresis parameter "a". The trapped gas saturation and residual oil saturation data of the six experimental cycles are shown in Table 3 below:

[0095] Table 3

[0096] cycle Sgt, ​​% (gas start) Sor, % (gas start) Sgt, ​​% (water starting) Sor, % (water starting point) 1 4.81 34.67 7.41 33.88 2 14.64 26.00 15.09 28.25 3 18.63 23.19 15.93 28.25 4 18.90 23.19 16.54 28.25 5 19.19 23.19 16.81 28.25 6 19.50 23.19 16.95 28.25

[0097] Since the residual oil saturation does not change from the fourth cycle, in order to reduce the calculation error, the data of the first three cycles are selected and substituted into the formula for fitting calculation. The calculation results are as follows: Figure 6As shown, the slope in the figure is the lag parameter "a".

[0098] According to the final results of the experimental data: gas drive starting "a" = 0.84, water drive starting "a" = 0.688.

[0099] (b) Calculation of hysteresis parameter “α”:

[0100] Different from the calculation method of parameter "a", the calculation of parameter "α" requires the experimental permeability data of adjacent cycles. Substituting the experimental data into formula (1) and other parameters can be calculated to obtain the hysteresis parameter "α". Taking n = 2 as an example, the other formula parameters for calculating the gas drive start hysteresis parameter "α" in formula (1) can be determined from the drainage curve and imbibition curve of the first and second cycles (such as Figure 7 As shown), water flooding starts as Figure 8 shown.

[0101] The final calculation results based on the experimental data are: gas drive starting "α" = 2.31, water drive starting "α" = 0.536.

[0102] (c) Calculation of the captured gas Land coefficient "C":

[0103] The initial gas saturation of each cycle in the six cycles of gas drive start and water drive start and the trapped gas saturation after the gas drive end were calculated from the experimental data, as shown in Table 4 below:

[0104] Table 4

[0105] cycle Sgi (gas start), % Sgr (gas start), % Sgi (water starting), % Sgr (water starting), % 1 3.04 41.87 2.01 39.91 2 13.36 46.57 6.07 47.52 3 16.64 45.46 16.31 49.58 4 16.77 46.03 17.50 50.67 5 16.81 46.64 17.67 51.57 6 16.91 47.41 17.81 52.09

[0106] Arrange the data and substitute it into formula (12) for fitting calculation. The calculation results are as follows: Fig. 9 shown.

[0107] The final calculation results based on the experimental data are: gas drive starting "C" = 2.1, water drive starting "C" = 1.89.

[0108] (3) Complete crude oil PVT fitting based on crude oil and degassing composition data combined with experimental data such as saturation pressure, gas-oil ratio, and MMP; The component data is obtained through chromatographic analysis, and the data is input into the simulator PVT fitting module to fit the key parameters such as MMP (minimum miscible pressure), gas-oil ratio, saturation pressure, viscosity, volume coefficient and relative volume. According to the data of crude oil analysis experiment report, the experimental value of crude oil MMP is 27.67MPa, the fitting value is 27.50MPa, the experimental measured viscosity of crude oil is 5.994cP, the fitting value is 5.754cP, and the experimental gas-oil ratio is 23.8m 3 / m 3 , fitted gas-oil ratio 23.68m 3 / m 3, the experimental saturation pressure is 5.09MPa, the fitting value is 5.14MPa, the experimental volume coefficient is 1.0816, the fitting volume coefficient is 1.0814, and the errors of all fitting items are within 5%, which meets the fitting requirements. (4) Establishing a core model in the simulator based on the experimental core physical data, and inputting hysteresis parameters to start the simulator hysteresis effect function; According to the experimental core physical data, a core model with the same size of 29×3×3 grids was established in the simulator (such as Fig.10 As shown in the figure, the first cycle gas-water two-phase permeability curve and gas-oil three-phase permeability curve measured in the experiment were input into the model. The model porosity was 0.23, the permeability was 215.69md, and the irreducible water saturation was 0.35. After the PVT fitting fluid was imported, the calculated hysteresis parameters were input to start the model phase permeability hysteresis simulation function, and the same conditions and injection parameters as the experiment were established in the model for simulation. (5) Output model recovery factor comparison experiment to verify the fitting effect. After the model is run, the model recovery factor results are output and compared with the experimental recovery factor results to see the fitting effect (such as Fig.11 ), from the recovery factor fitting results, the experimental recovery factors and model recovery factors at the beginning of gas drive and water drive are slightly different, indicating that the core model fitting effect is good, and the hysteresis parameters calculated by experiment have high accuracy and reliability, which can be directly applied to the subsequent mechanism model and geological model phase permeability hysteresis effect research. The above is only an embodiment of the present invention, and the common knowledge such as the known specific technical solutions and / or characteristics in the solution is not described in detail here. It should be pointed out that for those skilled in the art, without departing from the technical solution of the present invention, several modifications and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. An experimental design method for measuring phase permeability hysteresis parameters of high-temperature and high-pressure oil-bearing core gas-water alternation, characterized in that: The steps include: Step S1: Conduct high temperature and high pressure multi-cycle CO2-water alternating mutual drive experiments using actual reservoir cores and measure core relative permeability data; Step S2: determining a calculation method for hysteresis parameters of the phase permeability hysteresis model, wherein the calculation is divided into non-wetting phase permeability, wetting phase permeability and intermediate wetting phase permeability; Step S3: Select data based on the experimentally measured multi-cycle phase permeability curve data to calculate the hysteresis model hysteresis parameters a and α: Step S4: completing crude oil PVT fitting based on crude oil and degassing composition data combined with experimental data such as saturation pressure, gas-oil ratio, MMP, etc.; Step S5: Establish a core model in the simulator according to the experimental core physical data, and input hysteresis parameters to start the simulator hysteresis effect function; Step S6: Output the model recovery factor comparison experiment to verify the fitting effect.

2. The experimental design method for measuring phase permeability hysteresis parameters of high-temperature and high-pressure oil-bearing core gas-water alternating measurements as claimed in claim 1, characterized in that: In the step S1, the gas-water two-phase permeability curve, the water-oil three-phase permeability curve, and the gas-oil three-phase permeability curve are measured respectively, wherein the gas-water two-phase permeability experiment is directly carried out after the core is saturated with water for displacement measurement, and the oil-containing three-phase permeability experiment is to use active oil displacement to establish bound water after the core is saturated with water, and then gas drive or water drive is carried out to establish residual oil. Considering the influence of gas drive start and water drive start on the permeability hysteresis phenomenon, if gas drive is used to start to establish residual oil, a gas-water alternation experiment starting with six cycles of water drive is subsequently carried out, and vice versa; the gas-water two-phase permeability curve and the gas-oil, water-oil three-phase permeability curve of the reservoir core required for subsequent calculations are obtained through three types of permeability experiments, as well as their multi-cycle curve changes.

3. The experimental design method for measuring the phase permeability hysteresis parameters of the high-temperature and high-pressure oil-bearing core gas-water alternating measurement according to claim 1, characterized in that: The calculation of the non-wetting phase permeability in step S2 includes the following sub-steps: (a) Calculation of gas saturation scanning curve during displacement process Where: n---represents the number of cycles; take n=2 as an example, ---Relative permeability at Sg in the second drainage curve; ---Relative permeability at the first drainage Sg; --- Relative permeability of gas saturation at the starting point of the second drainage curve in the first drainage curve; ---Water saturation at the end of the second drainage; ---Water saturation at the starting point of the second drainage curve; S g --- Gas saturation in the second drainage curve; ---Gas saturation at the starting point of the second drainage curve; ---Relative permeability at gas saturation at the starting point of the second drainage curve in the first imbibition curve; (b) Calculation of gas saturation scanning curve during imbibition process Where: in: ---Gas saturation at the time of the nth cycle transition; (Sg) n ---Gas saturation in the nth cycle; --- Gas saturation at the end of the n-1th cycle; (S hi ) n --- Initial gas saturation of the nth cycle; ---Residual gas saturation at the time of the nth cycle conversion; (S gr ) n ---Residual gas saturation in the nth cycle.

4. The experimental design method for measuring phase permeability hysteresis parameters of high-temperature and high-pressure oil-bearing core gas-water alternating measurements as claimed in claim 3, characterized in that: Calculating the wetting phase permeability in step S2 includes the following sub-steps: (a) Calculation of water saturation scanning curve during imbibition process in: ---The first water phase relative permeability input; --- Second water phase relative permeability; --- Initial gas saturation; (S g ) max --- Maximum gas saturation; (b) Calculation of water saturation scanning curve during displacement process 1) If 2) If 3) If the gas saturation is constant in: ---Water phases infiltrate at the end of final imbibition.

5. The experimental design method for measuring phase permeability hysteresis parameters of high-temperature and high-pressure oil-bearing core gas-water alternating measurements as claimed in claim 4, characterized in that: The calculation of the intermediate wetting phase permeability in step S2 includes the following sub-steps: In the phase permeability hysteresis model, the oil phase relative permeability is a function of the oil saturation and the historical saturation, from which the intermediate wetting relative permeability can be calculated; Where: Sgt----trapped gas saturation after water flooding; Calculate the captured gas Land coefficient: Where: S gi ---Initial gas saturation, S gr --- Captured gas saturation; The hysteresis parameters input in the simulator are "a" and "α". After the hysteresis function is turned on in the simulator, the Land coefficient is input to represent the change of the captured gas saturation in the multi-cycle experiment. The hysteresis parameters are calculated by formula (1) and formula (11), and the captured gas coefficient is calculated by formula (12). in: "a" represents the reduction degree of residual oil saturation to oil phase relative permeability in the WAG simulation process; "α" is used to calculate the input parameter of the scanning curve during the displacement (i.e., increasing gas saturation), representing the reduction degree of relative permeability with the change of gas saturation; "C" represents the coefficient of variation of captured gas saturation at different periods.

6. The experimental design method for measuring the phase permeability hysteresis parameters of the high-temperature and high-pressure oil-bearing core gas-water alternating measurement according to claim 5, characterized in that: The step S3 also includes the following sub-steps: Step S31: Calculation of hysteresis parameter "a": According to the experimental results, the residual oil saturation at the start of gas drive and water drive in each of the six cycles and the trapped gas saturation at the end of water drive are respectively calculated and substituted into formula (11) to calculate the hysteresis parameter "a"; Step 32: Calculation of hysteresis parameter "α": To calculate parameter "α", phase permeability data of adjacent cycles in six-cycle experiments are required. Formula (1) and other parameters are substituted into the drainage curve and imbibition curve of adjacent cycles to obtain hysteresis parameter "α". Step 33: Calculation of the trapped gas Land coefficient "C": Based on the saturation data of the experimental results, the initial gas saturation in each of the six cycles at the beginning of gas drive and water drive, as well as the trapped gas saturation after the displacement, are statistically analyzed and substituted into formula (12) to calculate the trapped gas coefficient "C".

7. The experimental design method for measuring phase permeability hysteresis parameters of high-temperature and high-pressure oil-bearing core gas-water alternating measurements as claimed in claim 1, characterized in that: In step S4, the content of each component in the crude oil should be determined first, and the composition of each component in the crude oil and natural gas should be obtained by chromatographic analysis of the dead oil. The component data should be input into the simulator PVT module, and the well flow composition should be divided into pseudo-components. Then, according to the crude oil analysis experimental data, the key parameters of crude oil properties such as MMP (minimum miscibility pressure), gas-oil ratio, saturation pressure, viscosity, volume coefficient and relative volume should be fitted, and it should be ensured that the error between the experimental value and the fitting value is within 5%.

8. The experimental design method for measuring phase permeability hysteresis parameters of high-temperature and high-pressure oil-bearing core gas-water alternating measurements as claimed in claim 1, characterized in that: In step S5, a core model should be established in the simulator at a ratio of 1:1 based on the experimentally measured core physical data, and the experimentally measured gas-water relative permeability curve, gas-oil relative permeability curve, oil-water relative permeability curve, porosity, permeability and other data should be input. After the PVT-fitted fluid is imported, the hysteresis parameters "a" and "α" calculated based on the experimental data should be input to start the model relative permeability hysteresis simulation function, and the same experimental conditions and injection parameters should be established in the model for simulation.

9. The experimental design method for measuring phase permeability hysteresis parameters of high-temperature and high-pressure oil-bearing core gas-water alternating measurements as claimed in claim 1, characterized in that: The step S6 also includes: outputting the model recovery result after completing the model operation, and comparing it with the experimental recovery result to check the fitting effect. If the error between the final recovery rate of the model and the experimental recovery rate is not large, it means that the hysteresis parameters calculated by the experimental data are effective and can be applied to subsequent mechanism model or geological model research. If the error between the model recovery rate and the experimental recovery rate is large, the hysteresis parameters need to be adjusted.

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