A design method for profile control system and its performance indicators

Abstract

This invention discloses a design method for profile control systems and performance indicators, including establishing an application template for the profile control system; initially selecting the type of profile control system; determining the profile control system; determining the profile control system indicators; and optimizing the profile control system product. The method of this invention is applicable to the design of profile control systems and performance indicators for all oilfields. The method is universal and helps to standardize the design process and improve design quality. This invention organically combines laboratory experiments with field practice, making the design more able to meet the requirements of field reservoir applications, and also contributing to the timely summarization and improvement of profile control technology.

Description

Technical Field

[0001] This invention relates to the field of petroleum development technology, and in particular to a design method for selecting a suitable profile control system and performance indicators for profile control operations in water-injection oilfields. Background Technology

[0002] Water injection is the primary method for developing most oil reservoirs in my country. During water injection, factors such as reservoir heterogeneity and injection / production methods cause injected water to surge along high-permeability zones, resulting in a smaller injected volume and poorer development effectiveness. Profile control can effectively suppress the surge of injected water along high-permeability zones, expand the injected volume, and alleviate inter-layer, intra-layer, and planar heterogeneity, thereby improving the effectiveness of water injection development. Selecting a suitable profile control system and its performance indicators is a key aspect of achieving the expected profile control goals and also a challenge in profile control process design.

[0003] Currently, the design of profile control systems in China mainly relies on expert experience. Researchers are also exploring quantitative design methods, such as CN104573215A, a method for calculating the concentration and diameter of profile control agent particles. This method calculates the concentration and particle size of the first and second-level particulate profile control agents based on the injection pressure difference of the profile control well, formation porosity, formation permeability, expansion ratio of the profile control agent particles, and profile control depth. CN112201316A, a quantitative selection method for the gel strength of chromium gel used in deep oilfield profile control, calculates the compressive strength of the chromium gel after shearing and adsorption based on the target well data, profile control design injection parameters, and basic parameters of the chromium gel system. The strength is then compared with the pressure gradient at the target profile control well depth to determine if the chromium gel strength meets the requirements. CN111472736A, a patent for a combined profile control and displacement optimization design method and device for offshore oilfields, selects the crosslinking system, particulate profile control agent, and oil displacement system based on the target reservoir injection water and temperature. The performance and dosage of each system, injection sequence, and alternating injection rounds were screened using sand-filled pipe experiments. Finally, the total injection volume was adjusted according to the injection pressure during the field injection process. CN110029973A describes a method for improving the water drive effect of reservoirs using a multi-scale gel dispersion system, which provides well selection rules and methods for profile control, formulas for calculating profile control dosage, and design methods for profile control slugs in multi-scale gel dispersion systems (including slug types, dosages, and injection sequences). CN106372452B describes a method for designing the dosage of gel profile control and water shut-off agents. The method determines the radius of action for profile control and water shut-off by well test interpretation and calculates the dosage Q1 of gel profile control and water shut-off agents under this radius condition. The dosage Q2 of gel profile control and water shut-off agents under the water drive empirical method condition is obtained by measuring the formation water volume within the well group range. The dosage Q3 of gel profile control and water shut-off agents under the multi-channel plugging method condition is obtained by calculating the parameters of the crossflow channel. The arithmetic mean of Q1, Q2, and Q3 is taken as the dosage of profile control agent. However, existing technologies lack a universal design method for the profile control system and its performance indicators. Summary of the Invention

[0004] To address the lack of a universal design method for profile control systems and their performance indicators, this invention establishes a design method for profile control systems and their performance indicators. This method is based on factors such as the identification of dominant water flow channels, the characteristics of the profile control system, the compatibility of the profile control system with the reservoir, and historical profile control experience in the field. It guides the quantitative compilation and optimization of profile control systems, improving the relevance and accuracy of the design.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a design method for a profile adjustment system and its performance indicators, comprising the following steps:

[0006] Step 1: Establish application templates for profile control systems: Based on the characteristics of each type of profile control system, indoor experimental evaluation, field application status, and technical maturity, establish application templates for profile control systems. The templates include the reservoir temperature, formation water salinity, dominant channel development, and system characteristics that each type of profile control system is suitable for.

[0007] Step 2: Initial selection of profile control system type: Based on the reservoir temperature, formation water salinity, dominant channel development and application conditions of the target profile control well or block, and referring to the profile control system application template, the available profile control system types are initially selected.

[0008] Step 3: Determine the profile control system: Based on the initially selected profile control system type, determine one or more specific profile control systems to be applied according to the overall compatibility of the determined profile control system with the reservoir and the historical application of profile control systems in the target well or block.

[0009] Step 4: Determine the profile control system indicators: Based on the permeability of the dominant channels and high-permeability zones identified in the target well or block, compare the matching relationship between the profile control system and reservoirs with different permeability to determine the performance index values ​​or index ranges of the profile control system.

[0010] Step 5: Optimize profile control system products: Using the injection water from the target profile control well or block, conduct indoor evaluations of each profile control system product under the reservoir temperature conditions of the target profile control well or block. Under the premise that the performance indicators meet the requirements of Step 4, select the profile control system product with the best overall economic and technical performance by comparing other performance indicators and costs.

[0011] The method for establishing the matching relationship between the profile control system and reservoirs with different permeability in step 4 includes:

[0012] ① Filling the core with artificial sand-filled pipes;

[0013] ②Measure the core pore volume PV;

[0014] ③ Inject water and measure the water phase permeability;

[0015] ④ Prepare the profile control system: Prepare the profile control system according to the adjustment range of each system;

[0016] ⑤ Inject the profile control system: Inject the prepared profile control system into artificial cores with different permeabilities, and record the pressure changes at each pressure measurement point during the injection process;

[0017] ⑥ Re-inject water: Continue injecting water into the core until the pressure stabilizes, and record the pressure changes at each pressure measurement point during the injection process;

[0018] ⑦ Establish the matching relationship between the profile control system and reservoirs with different permeability: comprehensively evaluate the matching relationship between the profile control system and reservoirs with different permeability based on the system's injectability, deep migration performance, plugging performance, and erosion resistance. When the profile control system has good injectability, deep migration performance, plugging performance, and erosion resistance in a core of a certain permeability, it indicates that the system is matched with that permeability.

[0019] In step ⑦, the injectability is judged based on the pressure at the injection end when the profile control system is injected; the lower the injection pressure, the better the injectability. During the injection of the profile control system, the pressure at which pressure measurement point is activated indicates the position of the profile control system at which pressure measurement point it has moved to; the pressure at the pressure measurement point farther from the injection end indicates better deep migration performance of the profile control system. The sealing rate is calculated by the injection end pressure before and after the injection of the profile control system; the higher the sealing rate, the better the sealing performance. When water is injected again after the profile control system is injected, the larger the cumulative injection volume before the sudden drop in injection pressure, the better the scour resistance.

[0020] The application conditions in step 2 include well completion method, injection string, pressure rise window, construction safety, ease of process control, and injection method.

[0021] In step ①, the sand pipe is a steel pipe with a length of 1m and an inner diameter of 2.5cm. Pressure measuring points are set at distances of 10cm, 20cm, 40cm, 60cm and 80cm from the injection end. Artificial cores with different permeabilities are filled with river sand, formation sand or gravel. The permeability of the artificial core is determined according to the adaptability range of different profile control systems.

[0022] In step ③, the on-site prepared profile control system is filtered with water and injected into the artificial sand-filled core at flow rates of 0.5 ml / min, 1.0 ml / min, 2.0 ml / min, 3.0 ml / min, 4.0 ml / min, and 5.0 ml / min until the pressure stabilizes. During the injection process, the pressure change at each pressure measurement point is recorded, and the core water phase permeability at each flow rate is calculated. The arithmetic mean of these values ​​is the core water phase permeability.

[0023] In step ④, the profile control system of delayed cross-linking polymer gel is prepared with different concentrations of profile control system according to the recommended polymer concentration range corresponding to different gel strengths. The profile control system of bulk particles and microspheres is prepared with different particle sizes according to the recommended concentration range for different particle sizes.

[0024] In step ⑤, the prepared profile control system is injected into artificial cores with different permeabilities at a flow rate of 5 mL / min, with an injection volume of 1 PV. During the injection process, the pressure change at each pressure measurement point is recorded. For profile control systems based on delayed cross-linking polymer gels, after the profile control system is injected, both ends of the core tube are sealed and the core is left to stand at the temperature suitable for the profile control system for a certain period of time, which is not less than the cross-linking time of the system, before proceeding to the next step. For particulate and other profile control systems that do not require waiting for solidification, the next step can be carried out immediately after the profile control system is injected.

[0025] The beneficial effects of this invention are: the method is applicable to the design of all oilfield profile control systems and performance indicators; the method is universal, which helps to standardize the design process and improve design quality. This invention organically combines laboratory experiments with field practice, making the design more able to meet the requirements of field reservoir applications, and also helps to summarize and improve profile control technology in a timely manner. Detailed Implementation

[0026] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present invention.

[0027] The design method of the profile control system and performance indicators of the present invention includes the following steps:

[0028] Step 1: Establish application templates for profile control systems: Based on the characteristics, indoor experimental evaluations, field application status, and technological maturity of each type of profile control system, establish application templates for the profile control system. The templates include the reservoir temperature, formation water salinity, dominant channel development, and system characteristics that each type of profile control system is suitable for.

[0029] Step 2: Initial selection of profile control system type: Based on the reservoir temperature, formation water salinity, dominant channel development and other application conditions of the target profile control well or block (such as completion method, injection string, pressure rise window, construction safety, ease of process control, injection method, etc.), and referring to the profile control system application template, the available profile control system type is initially selected.

[0030] Step 3: Determine the profile control system: Based on the initially selected profile control system type, determine one or more specific profile control systems to be applied according to the overall compatibility of the determined profile control system with the reservoir and the historical application of profile control systems in the target well or block.

[0031] Step 4: Determine the profile control system indicators: Based on the permeability of the dominant channels and high-permeability zones identified in the target well or block, compare the matching relationship between the profile control system and reservoirs with different permeability to determine the performance index values ​​or index ranges of the profile control system.

[0032] This step involves establishing the compatibility between the profile control system and reservoirs with different permeability levels, as follows:

[0033] ① Filling artificial sand-filled core tubes

[0034] The sand-filling pipe is a steel pipe, 1m long, with an inner diameter of 2.5cm. Pressure measuring points are located at 10cm, 20cm, 40cm, 60cm, and 80cm from the injection end. Artificial cores with different permeabilities are prepared using river sand, formation sand, or gravel. The permeability of the artificial cores is determined based on the adaptability range of different profile control systems.

[0035] ② Measuring the core pore volume PV

[0036] ③ Inject water and measure the water phase permeability

[0037] After filtering water, the on-site prepared profile control system was injected into artificial sand-filled cores at flow rates of 0.5 ml / min, 1.0 ml / min, 2.0 ml / min, 3.0 ml / min, 4.0 ml / min, and 5.0 ml / min until the pressure stabilized. Pressure changes at each pressure measurement point were recorded during the injection process. The water permeability of the core at each flow rate was calculated, and the arithmetic mean was taken as the water permeability of the core.

[0038] ④Preparation of the profile control system

[0039] The profile control system should be formulated according to the adjustment range of each system. For example, for the profile control system of delayed crosslinking polymer gel, different concentrations (corresponding to different gel strengths) should be formulated according to the recommended polymer concentration range. For the profile control systems of bulk particles and microspheres, different particle size profile control systems should be formulated according to the recommended concentration range for different particle sizes.

[0040] ⑤ Injection of profile control system

[0041] The prepared profile control system was injected into artificial cores with different permeabilities at a flow rate of 5 mL / min, with an injection volume of 1 PV. Pressure changes at each pressure measurement point were recorded during injection. For profile control systems based on delayed cross-linking polymer gels, after injection, both ends of the core tube were sealed and allowed to stand at the system's suitable temperature for a period not less than the system's cross-linking time before proceeding to the next step. For particulate and other profile control systems that do not require waiting for solidification, the next step could proceed immediately after injection.

[0042] ⑥ Refill with water

[0043] Continue injecting water into the core until the pressure stabilizes, and record the pressure changes at each pressure measurement point during the injection process.

[0044] ⑦ Establish the matching relationship between the profile control system and reservoirs with different permeability.

[0045] The compatibility of a profile control system with reservoirs of different permeability is comprehensively evaluated based on its injectability, deep migration performance, plugging performance, and erosion resistance. When a profile control system exhibits good injectability, deep migration performance, plugging performance, and erosion resistance in a core of a certain permeability, it indicates that the system is compatible with that permeability.

[0046] Injectability is judged by the pressure at the injection end when injecting into the profile control system; the lower the injection pressure, the better the injection performance.

[0047] During the injection process of the profile control system, the number of pressure measurement points at which the system begins to pressurize indicates the location of that pressure measurement point. The farther the pressure measurement point is from the injection end, the better the deep migration performance of the profile control system.

[0048] The plugging rate is calculated by the injection end pressure before and after the injection of the profile control system. The higher the plugging rate, the better the plugging performance.

[0049] When injecting water after injecting into the profile control system, the larger the cumulative injection volume before the injection pressure suddenly drops, the better the erosion resistance.

[0050] Step 5: Optimize profile control system products: Using the injection water from the target profile control well or block, conduct indoor evaluations of each profile control system product under the reservoir temperature conditions of the target profile control well or block. Under the premise that the performance indicators meet the requirements of Step 4, select the profile control system product with the best overall economic and technical performance by comparing other performance indicators and costs.

[0051] The design of the overall profile control system for the G80 fault block in the WGT oilfield is used as an example for detailed explanation.

[0052] Step 1: Establish a profile control system application template

[0053] There are five types of profile control systems available for optimization in this oilfield. Based on the principles, characteristics, experimental evaluations, and application status of each profile control system, an application template for the profile control system is established.

[0054] Table 1 Application Template for Profile Adjustment System

[0055]

[0056]

[0057] Step 2: Initial selection of profile control system type

[0058] A total of 8 injection wells were deployed for the overall profile control of the G80 fault block. The reservoir temperature ranges from 75 to 90°C, with an average of 88°C. It is a high-temperature profile control reservoir, and the temperature resistance performance needs to be considered when selecting the profile control system.

[0059] The formation water in the G80 fault block is of the calcium chloride type, with a total mineralization of 30,633 mg / L; the injected water is also of the calcium chloride type, with a total mineralization of 23,421 mg / L, both of which are considered high mineralization. During the on-site profile control process, the injected water was used to prepare the profile control fluid. This fluid comes into contact with the formation water after entering the formation; therefore, salt tolerance needs to be considered when selecting the profile control system.

[0060] The dominant flow channels in the G80 fault block are severely developed. Dominant channel identification results indicate that the maximum permeability of the dominant channels in this fault block is 8154 × 10⁻⁶. -3 μm 2 The average injection pressure of the 8 injection wells is only 1.7 MPa, and the injection pressure of 5 wells is 0. The formation is self-absorbing water and the water flow dominance channels are severely developed. The profile control system is required to be adapted to high-permeability reservoirs and have high plugging strength.

[0061] In summary, the G80 fault block is characterized by high temperature and salinity, and severe development of water-dominant channels. Furthermore, the overall profile control injection volume is large, with a construction period exceeding six months. Therefore, the selected profile control system must be safe to implement and easy to control. Microspheres in the profile control system template are primarily used in low-permeability reservoirs and are not suitable for this fault block. Coated gels and inorganic composite profile control systems require high control during construction and are relatively complex, making them unsuitable for large-volume, long-term injections. Delayed cross-linking polymer gels and bulk-swelling particles are suitable for reservoirs with dominant channels and can be adapted to a wider range of reservoirs by adjusting strength or particle size. They are also relatively safe to implement and are therefore initially selected as the system for this overall profile control project in the G80 fault block.

[0062] Step 3: Determine the profile control system

[0063] The results of the profile control system matching experiment and historical application show that the delayed cross-linking polymer gel is suitable for medium-low permeability to high permeability reservoirs with well-developed water flow dominant channels or high permeability zones, while the bulky particles are suitable for medium-to-ultra-high permeability reservoirs with severely developed water flow dominant channels. The combined application of the two can be applied to reservoirs ranging from high permeability to those with severely developed water flow dominant channels, and has a wide range of applicable reservoirs. Depending on the specific conditions of each well, a single delayed cross-linking polymer gel profile control system or a combined delayed cross-linking polymer gel and bulky particle profile control system can be selected.

[0064] Of the 288 wells in the WGT oilfield where the G80 fault block is located, 253 used a composite profile control system of delayed cross-linking polymer gel and bulk-swelling particles. The average oil increase per well group was 126 tons higher than other profile control systems, and the application effect was very good.

[0065] In summary, the overall profile control system for the G80 fault block was determined to be a composite profile control system of delayed cross-linking polymer gel and bulk-swelling particles.

[0066] Step 4: Determine the performance indicators of the profile control system

[0067] After determining the type of profile control system, it is also necessary to determine the performance indicators of each type of profile control system, namely the strength of the delayed cross-linked polymer gel and the particle size of the bulk-swelling particles. In the early stage, the matching relationship between different strengths of delayed cross-linked polymer gels, different particle sizes of bulk-swelling particles and reservoirs with different permeability has been established through physical model experiments. By comparing the permeability of the identified water flow dominant channels with the matching relationship, the performance indicator values ​​can be determined.

[0068] Table 2. Matching relationship between bulked particles and reservoirs with different permeabilities

[0069]

[0070] Table 3. Matching relationship between delayed crosslinking polymer gels and reservoirs with different permeabilities.

[0071]

[0072] The dominant water flow channels in the G80 fault block were identified, with permeability ranging from (3258 to 8154) × 10⁻⁶. -3 μm 2 Between these values, the gel strength of the delayed crosslinking polymer matched within this permeability range is (6–8) × 10⁻⁶. 4 The pressure is above mPa·s, and the particle size of the bulky particles is 2-4 mm. Considering that in high-dose deep profile control, it is necessary not only to block the dominant water flow channels but also to manage the high-permeability zone to maximize the adjustment of reservoir heterogeneity and expand the swept volume, it is also necessary to inject a less strong delayed cross-linking polymer gel. Therefore, the performance index of the delayed cross-linking polymer gel profile control system used for the overall profile control of the G80 fault block is designed as a gel strength of (4-8)×10. 4 The performance index of the body-expanding granular profile control agent is above mPa·s, and the particle size is 2-4 mm.

[0073] Step 5: Select the best profile control system products

[0074] Each type of profile control system generally has many products, especially delayed cross-linking polymer gels and bulk-swelling particles, which are the main systems for profile control. There are even more products, so it is necessary to determine the specific products.

[0075] First, we collected profile control system products. A total of four delayed cross-linking polymer gel profile control system products and four bulk-swelling particle products were collected.

[0076] Delayed crosslinking polymer gel profile control systems were prepared using G80 fragment injection water. Three concentrations of each product were prepared, and their gel strength at 90℃, gelation time, and 90-day strength retention were investigated. Experimental results showed that only one of the four delayed crosslinking polymer gel profile control systems produced a gel with the highest concentration. # and 2 # Two products have a gel strength of (4-8)×10⁻⁶. 4 mPa·s, meeting design requirements; 1 # and 2 # The gelation time of the products is suitable and can meet the application requirements, but 1 # The product has a wider strength adjustment range, a higher 90-day strength retention rate, and lower reagent costs for the same strength; therefore, it was determined that 1 # The delayed cross-linking polymer gel product is a delayed cross-linking polymer gel profile control system for overall profile control of G80 fracture blocks.

[0077] After testing the particle size and density of the expanded granules, the expansion ratio, strength, and 90-day strength retention rate of each product were evaluated under G80 fracture-type water injection and at 90℃. Experimental results show that the particle size of all four products can be processed to 2–4 mm as needed, meeting design requirements; the expansion ratio also meets application requirements of 5–40 times; however, product A has the lowest density (1.15 g / cm³). 3 The product A, with the highest strength and 90-day strength retention rate and a moderate price, was selected as the bulk-expanded particle product for the overall sectioning of G80 fracture blocks.

[0078] In summary, through the above five steps, a composite profile control system of delayed cross-linking polymer gel and bulk-swelling particles was designed for the overall profile control of the G80 fault block. The delayed cross-linking polymer gel was selected from a specific type. # Delayed cross-linking polymer gel products, gel strength 4~8×10 4 mPa.s, the bulky granules selected are bulky granule product A, with a particle size of 2-4mm.

[0079] In summary, the content of this invention is not limited to the above-described embodiments. Those skilled in the art can easily propose other embodiments within the technical guiding principles of this invention, but such embodiments are all included within the scope of this invention.

Claims

1. A profile control system and a performance index design method, characterized in that, Includes the following steps: Step 1: Establish application templates for profile control systems: Based on the characteristics of each type of profile control system, indoor experimental evaluation, field application status, and technical maturity, establish application templates for profile control systems. The templates include the reservoir temperature, formation water salinity, dominant channel development, and system characteristics that each type of profile control system is suitable for. Step 2: Initial selection of profile control system type: Based on the reservoir temperature, formation water salinity, dominant channel development and application conditions of the target profile control well or block, and referring to the profile control system application template, the available profile control system types are initially selected. Step 3: Determine the profile control system: Based on the initially selected profile control system type, determine one or more specific profile control systems to be applied according to the overall compatibility of the determined profile control system with the reservoir and the historical application of profile control systems in the target well or block. Step 4: Determine the profile control system indicators: Based on the permeability of the dominant channels and high-permeability zones identified in the target well or block, compare the matching relationship between the profile control system and reservoirs with different permeability to determine the performance index values ​​or index ranges of the profile control system. Step 5: Select profile control system products: Using the injection water from the target profile control well or block, conduct indoor evaluations of each profile control system product under the reservoir temperature conditions of the target profile control well or block. Under the premise that the performance indicators meet the requirements of Step 4, select the profile control system product with the best overall economic and technical performance by comparing other performance indicators and costs. The method for establishing the matching relationship between the profile control system and reservoirs with different permeability in step 4 includes: ① Filling the rock core with artificial sand-filled pipes; ②Measure the core pore volume PV; ③ Inject water and measure the water phase permeability; ④ Prepare the profile control system: Prepare the profile control system according to the adjustment range of each system; ⑤ Inject the profile control system: Inject the prepared profile control system into artificial cores with different permeabilities, and record the pressure changes at each pressure measurement point during the injection process; ⑥ Re-inject water: Continue injecting water into the core until the pressure stabilizes, and record the pressure changes at each pressure measurement point during the injection process; ⑦ Establish the matching relationship between the profile control system and reservoirs with different permeability: comprehensively evaluate the matching relationship between the profile control system and reservoirs with different permeability based on the system's injectability, deep migration performance, plugging performance, and erosion resistance. When the profile control system has good injectability, deep migration performance, plugging performance, and erosion resistance in a core of a certain permeability, it indicates that the system is matched with that permeability.

2. The profile control system and performance index design method according to claim 1, characterized in that, In step ⑦, the injectability is judged based on the pressure at the injection end when the profile control system is injected; the lower the injection pressure, the better the injectability. During the injection of the profile control system, the pressure at which pressure measurement point is activated indicates the position of the profile control system at which pressure measurement point it has moved to; the pressure at the pressure measurement point farther from the injection end indicates better deep migration performance of the profile control system. The sealing rate is calculated by the injection end pressure before and after the injection of the profile control system; the higher the sealing rate, the better the sealing performance. When water is injected again after the profile control system is injected, the larger the cumulative injection volume before the sudden drop in injection pressure, the better the scour resistance.

3. The profile control system and performance index design method of claim 1, wherein, The application conditions in step 2 include well completion method, injection string, pressure rise window, construction safety, ease of process control, and injection method.

4. The design method for the profile adjustment system and performance indicators according to claim 1, characterized in that, In step ①, the sand pipe is a steel pipe with a length of 1m and an inner diameter of 2.5cm. Pressure measuring points are set at distances of 10cm, 20cm, 40cm, 60cm and 80cm from the injection end. Artificial cores with different permeabilities are filled with river sand, formation sand or gravel. The permeability of the artificial core is determined according to the adaptability range of different profile control systems.

5. The design method for the profile control system and performance indicators according to claim 1, characterized in that, In step ③, the on-site prepared profile control system is filtered with water and injected into the artificial sand-filled core at flow rates of 0.5 ml / min, 1.0 ml / min, 2.0 ml / min, 3.0 ml / min, 4.0 ml / min, and 5.0 ml / min until the pressure stabilizes. During the injection process, the pressure change at each pressure measurement point is recorded, and the core water phase permeability at each flow rate is calculated. The arithmetic mean of these values ​​is the core water phase permeability.

6. The design method for the profile adjustment system and performance indicators according to claim 1, characterized in that, In step ④, the profile control system of delayed cross-linking polymer gel is prepared with different concentrations of profile control system according to the recommended polymer concentration range corresponding to different gel strengths. The profile control system of bulk particles and microspheres is prepared with different particle sizes and different concentrations according to the recommended concentration range for different particle sizes.

7. The design method for the profile adjustment system and performance indicators according to claim 1, characterized in that, In step ⑤, the prepared profile control system is injected into artificial cores with different permeabilities at a flow rate of 5 mL / min, with an injection volume of 1 PV. During the injection process, the pressure change at each pressure measurement point is recorded. For profile control systems based on delayed cross-linking polymer gels, after the profile control system is injected, both ends of the core tube are sealed and the core is left to stand at the temperature suitable for the profile control system for a certain period of time, which is not less than the cross-linking time of the system, before proceeding to the next step. For particulate and other profile control systems that do not require waiting for solidification, the next step can be carried out immediately after the profile control system is injected.

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