A method for evaluating the effect of a heterogeneous composite flooding

Abstract

The present application belongs to the technical field of oilfield development, and particularly relates to a method for evaluating the effect of heterogeneous composite flooding. The method uses the ratio of the pressure difference between the injection well and the production well to the difference between the injection rate at the injection end and the liquid production rate at the production end to represent the resistance coefficient. The resistance coefficients at the injection end and the production end before and after the flooding are calculated respectively, and the cumulative resistance coefficient proportion S is calculated after the resistance coefficients are sorted i and the cumulative well pair proportion T i . The Lorenz curve is drawn with the cumulative resistance coefficient proportion S i and the cumulative well pair proportion T i as the longitudinal coordinate and the lateral coordinate respectively, the displacement balance degree grade is determined through the Lorenz coefficient, the scientific quantitative evaluation of the flooding effect is realized, the basis for the selection of the flooding method is provided, and the oilfield development efficiency is improved.

Description

Technical Field

[0001] This invention belongs to the field of oilfield development technology, specifically relating to a method for evaluating the effectiveness of heterogeneous composite flooding. Background Technology

[0002] During oilfield development, as extraction time increases, reservoir water cut rises, posing challenges to improving oil recovery. Heterogeneous composite flooding, as an important enhanced oil recovery technology, involves injecting viscoelastic particles, polymers, etc., into the reservoir. Utilizing their migration, sealing, and moderating effects within the formation, it improves reservoir flow conditions, thereby enhancing crude oil recovery.

[0003] Currently, the evaluation of the effects of heterogeneous composite flooding is mainly based on empirical judgment and simple production dynamic analysis, lacking scientific and quantitative evaluation methods. Existing evaluation methods are insufficient to accurately reflect the degree of displacement equilibrium in the reservoir during the flooding process, and cannot provide a reliable basis for the selection and optimization of flooding methods. Specifically, existing technologies have the following shortcomings: a lack of effective quantitative indicators to evaluate the degree of displacement equilibrium, making it difficult to scientifically judge the effects of flooding; a lack of targeted optimization methods for flooding schemes for well groups with different degrees of displacement equilibrium, leading to unstable flooding effects; and a lack of clear standards and methods for verifying the effects of flooding, making it difficult to accurately assess the effectiveness of flooding measures.

[0004] Therefore, there is an urgent need for a scientific and quantitative method for evaluating the effect of heterogeneous composite flooding, in order to improve the accuracy and reliability of the evaluation of the effect of the flooding, provide a basis for the selection and optimization of the flooding method, and thus improve the efficiency of oilfield development. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a method for evaluating the effectiveness of heterogeneous composite flooding. The method uses the ratio of the pressure difference between the injection and production wells to the difference between the injection rate at the injection end and the production rate at the production end to represent the resistance coefficient. By calculating the resistance coefficients at both the injection and production ends before and after flooding adjustment, and sorting the resistance coefficients, the cumulative resistance coefficient ratio S is calculated. i and cumulative well ratio T i The cumulative drag coefficient ratio S i and cumulative well ratio T i Lorentz curves are plotted on the vertical and horizontal axes, and the displacement balance level is determined by the Lorentz coefficient, so as to realize the scientific quantitative evaluation of the displacement effect and provide a basis for the selection of displacement methods.

[0006] The technical problem to be solved by this invention is achieved by the following technical solution: a method for evaluating the effect of heterogeneous composite flooding, comprising the following steps:

[0007] S1. Collection of well group data

[0008] Production dynamics data at both injection and production ends in the well group before and after the adjustment and drive were collected using equal time series.

[0009] S2. Calculate the drag coefficients before and after drive adjustment.

[0010] The formula for calculating the resistance coefficient between the injection end and the extraction end is as follows:

[0011] ;

[0012] In the formula, P1 is the pressure at the injection end (Pa); P2 is the pressure at the extraction end (Pa); and Q1 is the injection velocity at the injection end (m). 3 / s; Q2 is the production rate at the extraction end, m 3 / s;

[0013] Based on the production dynamic data of both injection and production ends before the adjustment and drive, read the injection rate at the injection end before the adjustment and drive, the production rate at the production end, read the pressure at both injection and production ends before the adjustment and drive, and calculate the resistance coefficient between each injection end and production end before the adjustment and drive.

[0014] Based on the production dynamic data of the injection and production ends after adjustment, the injection rate of each injection end and the production rate of each production end after adjustment are read, the pressure of each injection and production end after adjustment are read, and the resistance coefficient between each injection end and production end after adjustment is calculated.

[0015] S3. Calculate the Lorentz coefficient of the well group before and after the drive adjustment.

[0016] Based on the resistance coefficients between the injection and production ends before and after the adjustment, the Lorentz coefficient L of the well group before and after the adjustment is calculated respectively.

[0017] S4. Determine the displacement balance level.

[0018] The degree of displacement equilibrium is determined by the Lorentz coefficient L, and the levels are classified as follows:

[0019] L<0.3: First-order equilibrium;

[0020] 0.3≤L<0.5: Second-order equilibrium;

[0021] 0.5≤L<0.7: Three-level equilibrium;

[0022] 0.7≤L≤1: Level 4 equilibrium;

[0023] The displacement adjustment scheme is adjusted according to the equilibrium level. The drag coefficient formula of this invention is directly derived from a modification of Darcy's linear flow formula; by directly calculating the drag coefficient, the displacement equilibrium before and after adjustment is determined, thereby evaluating the effect of displacement adjustment of viscous heterogeneous composite flooding.

[0024] Preferably, this invention also includes S5, evaluating the effect of the drive adjustment, which is judged based on the ratio M of the Lorentz coefficient before and after the drive adjustment. The main judgment levels are as follows:

[0025] M<1: Poor performance;

[0026] 1≤M<2: Moderate effect;

[0027] 2≤M<3: Good results;

[0028] M≥3: Good effect. The ratio of the Lorentz coefficient before and after adjustment is determined by both values. For example, if the Lorentz coefficient before adjustment is 0.7 and the value after adjustment is >0.7 (or =0.7), meaning the Lorentz coefficient after adjustment is larger and closer to 1, indicating a more unbalanced effect, it can be directly judged that the adjustment effect has deteriorated. In this case, the ratio of the Lorentz coefficient before and after adjustment is M≤1, and this category is classified as poor effect, thus setting different effect levels. The evaluation based on the adjustment effect can verify the correctness of the initial diagnosis and the current development strategy.

[0029] Preferably, in step S4 of this invention, adjusting the drive scheme according to the balance level specifically involves:

[0030] When the level is Level 1 Balance, no adjustment is required.

[0031] When the level is two-stage equalization, polymer-modulated drive is used;

[0032] When the level is three-level equilibrium, particles are used for sealing and regulation.

[0033] When the equilibrium level is four, the combined chemical agent and particle regulation are used.

[0034] In a preferred embodiment of the present invention, the specific calculation method for the Lorentz coefficient L of the well group before and after the adjustment and drive in step S3 is as follows:

[0035] The n drag coefficient values ​​C obtained before and after the drive adjustment are sorted in ascending order to obtain a new sequence. The cumulative drag coefficient ratio S is then calculated according to the formula. i Cumulative well ratio T i ;

[0036] Then, using the cumulative well ratio T i The x-axis represents the cumulative drag coefficient S. i Plot the Lorentz curve with the vertical axis as the ordinate;

[0037] Calculate the area A between the Lorentz curve and the absolute equilibrium line y=x, and the area B of the triangle below the absolute equilibrium line, to determine the Lorentz coefficient L.

[0038] The formulas for the cumulative resistance coefficient ratio, the cumulative well-to-well ratio, and the Lorentz coefficient are as follows:

[0039]

[0040]

[0041]

[0042] In the formula, C i C j All are drag coefficients, calculated from the formula corresponding to drag coefficient C. i and j are subscripts, representing the permutation numbers corresponding to drag coefficient C, where j ≤ i; S i T represents the cumulative drag coefficient ratio; i is the cumulative well-to-well ratio; L is the Lorentz coefficient; n is related to the number of injection points and production points, and adjacent injection points and production points generate a resistance coefficient value.

[0043] In a preferred embodiment of the present invention, in step S1, production dynamic data before and after the drive adjustment are collected at a frequency of 5 to 30 minutes / time with equal time series.

[0044] In a preferred embodiment of this invention, step S4 verifies the effectiveness by monitoring the decrease in maximum internal water cut and the increase in recovery rate after the adjustment. Before adjustment, due to the strong heterogeneity of the reservoir (i.e., extremely low "equilibrium"), injected water concentrates in a few high-permeability zones, leading to rapid water flooding of production wells and persistently high water cut. After adjustment, the adjustment agent preferentially enters high-permeability channels, increasing their flow resistance. This causes subsequent injection pressure to rise, forcing the injected fluid to redirect towards medium and low-permeability layers. This process directly improves the "equilibrium" of the injection profile and pressure field. Therefore, the production response of the adjustment is: as high-permeability channels are effectively controlled, the proportion of crude oil from low-permeability layers increases and the proportion of water decreases in the fluid produced from the well, thus observing a "decrease in maximum internal water cut." Therefore, the decrease in water cut and the increase in oil content are the most direct and sensitive evidence of improved underground flow field equilibrium.

[0045] The inventive concept of this invention is as follows: Oilfield production typically begins with water flooding. Only when water flooding proves ineffective are chemical flooding, particle flooding, or polymer flooding used to enhance production. This invention utilizes a two-dimensional flat plate model for simulation experiments, discovering that the Lorentz coefficient can be calculated using the resistance coefficients at both the injection and production ends before and after flooding adjustments. The displacement balance level is then determined based on the magnitude of the Lorentz coefficient. The Lorentz coefficient calculated before flooding adjustments (e.g., water flooding) can indicate the displacement effect before adjustments; if the displacement effect is poor, flooding adjustments are necessary. The displacement effect after flooding adjustments is then obtained by calculating the Lorentz coefficient after adjustments, allowing for subsequent evaluation of the adjustments. Through this method, this invention summarizes flooding adjustment schemes corresponding to different balance levels, providing a basis for the selection and optimization of flooding adjustment methods in actual production.

[0046] In this invention, the Lorentz coefficient is a parameter reflecting the equilibrium. The closer it is to 0, the more balanced the displacement; the closer it is to 1, the less balanced the displacement. Therefore, based on the idea of ​​averaging, this invention divides the equilibrium level into 4 levels and sets different adjustment methods based on different equilibrium levels.

[0047] Compared with the prior art, the beneficial effects of the present invention are:

[0048] This invention collects production dynamic data from both the injection and production ends of well groups before and after well relocation. The resistance coefficient is represented by the ratio of the pressure difference between the injection and production ends to the difference between the injection rate at the injection end and the production rate at the production end. By calculating the resistance coefficients at both the injection and production ends before and after well relocation, the resistance coefficients are sorted and the cumulative resistance coefficient ratio S is calculated. i and cumulative well ratio T i Then, using the cumulative resistance coefficient ratio S i The vertical axis is T, and the cumulative well scale is T. i A Lorentz curve is plotted on the horizontal axis, and the displacement balance level is determined based on the magnitude of the Lorentz coefficient. This invention achieves a scientific evaluation of the displacement balance effect by quantifying the displacement balance, providing a basis for the selection of displacement methods and helping to improve oilfield development efficiency. Attached Figure Description

[0049] Figure 1 This is a flowchart of the method for evaluating the effect of heterogeneous composite flooding in an embodiment of the present invention;

[0050] Figure 2 This is a schematic diagram of the layout of the two-dimensional flat plate experimental model in an embodiment of the present invention;

[0051] Figure 3 This is a schematic diagram illustrating the drawing of the Lorentz curve and the calculation of its area according to an embodiment of the present invention. Detailed Implementation

[0052] The technical solutions in the embodiments of the present invention will now be clearly and completely described in conjunction with the accompanying drawings.

[0053] Terminology Explanation:

[0054] Level 1 equilibrium, Level 2 equilibrium, Level 3 equilibrium, Level 4 equilibrium: In this invention, the degree of displacement equilibrium between the injection end and the production end is divided into four levels according to the Lorentz coefficient L of the water flooding or chemical flooding equilibrium. The higher the level, the worse the equilibrium.

[0055] like Figure 1 As shown, a method for evaluating the effect of heterogeneous composite flooding utilizes the Lorentz coefficient to classify the degree of displacement equilibrium and evaluates the effect of flooding adjustment based on the ratio of the Lorentz coefficient before and after adjustment. Figure 1 As shown, the method for evaluating the effect of heterogeneous composite flooding includes the following steps:

[0056] S1. Collection of well group data

[0057] This embodiment selects a two-dimensional flat plate model for simulation experiments. An existing two-dimensional flat plate model is used, with injection points and multiple extraction points set on it. The two-dimensional flat plate model has 25 injection and extraction ends, and the specific arrangement of the injection and extraction ends is as follows: Figure 2 As shown, water or displacement fluid is injected into the injection end using an injection pump to simulate water flooding or chemical flooding experimental scenarios, and data such as porosity and permeability are collected.

[0058] The distance between the injection end and the production end is preferably 3~10cm. Before the well group is adjusted, the water cut is ≥70%. Basic parameters such as porosity are collected. Production dynamic data before and after the adjustment are collected at a frequency of 5~30min / time, including injection rate, production rate, injection-production pressure difference, etc.

[0059] Production dynamics data at both ends of the injection and production in the well group before and after the adjustment were collected using equal time series, as shown in Table 1.

[0060] Table 1 Simulation test data

[0061]

[0062] In this embodiment, when the water content is 70%, the four adjacent injection and extraction ends (e.g., at the upper left corner of the two-dimensional flat plate model) are collected before the driving is adjusted. Figure 2 The pressure and flow rate values ​​(shown in the rectangular box) are shown in Tables 2 and 3:

[0063] Table 2 Pressure values ​​(kPa) before drive adjustment

[0064]

[0065] Table 3. Flow velocity values ​​before the adjustment (m) 3 / s)

[0066]

[0067] After adjusting the drive, the four adjacent injection and acquisition ends in the upper left corner of the two-dimensional flat plate model are collected (e.g., Figure 2 The pressure and flow rate values ​​(shown in the rectangular box) are shown in Tables 4 and 5:

[0068] Table 4. Pressure values ​​(kPa) after adjustment.

[0069]

[0070] Table 5. Flow velocity values ​​after adjustment (m) 3 / s)

[0071]

[0072] S2. Calculate the drag coefficients before and after drive adjustment.

[0073] The formula C1 = (90-83) / (15-10.1) = 1.43 is calculated below. Similarly, the resistance coefficients for the other groups are calculated to be 3.57, 1.89, and 1.22, respectively. The formula for calculating the resistance coefficient between the injection end and the extraction end is as follows:

[0074] ;

[0075] In the formula, P1 is the pressure at the injection end (Pa); P2 is the pressure at the extraction end (Pa); and Q1 is the injection velocity at the injection end (m). 3 / s; Q2 is the production rate at the extraction end, m 3 / s.

[0076] Before the adjustment, water drive is performed. Based on the production dynamic data of the injection and production ends of the water drive before the adjustment, the injection rate at the injection end and the production rate at the production end are read. The pressures at the injection and production ends before the adjustment are read, and the resistance coefficients between each injection end and production end before the adjustment are calculated.

[0077] Chemical flooding was selected for the adjustment. Based on the production dynamic data of the injection and production ends of the chemical flooding after adjustment, the injection rate of each injection end and the production rate of each production end were read. The pressure of each injection and production end after adjustment was read, and the resistance coefficient between each injection end and production end after adjustment was calculated.

[0078] S3. Calculate the Lorentz coefficient of the well group before and after the drive adjustment.

[0079] Based on the resistance coefficients between the injection and production ends before and after the adjustment, the Lorentz coefficient L of the well group before and after the adjustment is calculated respectively.

[0080] Before adjusting the drive, S1 = 1.22 / (1.43 + 3.57 + 1.89 + 1.22) = 0.15. Similarly, S2 = 0.33, S3 = 0.56, and S4 = 1.

[0081] T1=i / n=1 / 4, T2=i / n=2 / 4, T3=i / n=3 / 4, T4=i / n=1.

[0082] According to S i T i Draw a graph and calculate the Lorentz coefficient as L = 0.5 / (1 - 0.378) = 0.80.

[0083] Similarly, the drag coefficient after adjustment is calculated to be 0.45.

[0084] S4. Determine the displacement balance level.

[0085] The degree of displacement equilibrium is determined by the Lorentz coefficient L, and the levels are classified as follows:

[0086] L<0.3: First-order equilibrium;

[0087] 0.3≤L<0.5: Second-order equilibrium;

[0088] 0.5≤L<0.7: Three-level equilibrium;

[0089] 0.7≤L≤1: Level 4 equilibrium;

[0090] Adjust the drive tuning scheme according to the balance level. In step S4, adjusting the drive tuning scheme according to the balance level specifically involves:

[0091] When the level is Level 1 equilibrium, the waterline advances evenly, water is seen late, and the water cut rises slowly, so no adjustment is required.

[0092] When the waterline advance is at level two equilibrium, it becomes uneven, with unidirectional surges and a faster rise in water content. Therefore, polymer-modified drive is adopted.

[0093] When the water content is at level three equilibrium, the water level rises rapidly, and there may be obvious high-permeability bands, large channels, or even cracks. Therefore, granules are used for plugging and regulation.

[0094] At level four equilibrium, combined chemical agents and particle-based propulsion are used. In this embodiment, the waterline propulsion is observed through a glass window of a two-dimensional flat plate model.

[0095] Based on an L value of 0.80, the equilibrium level before displacement was determined to be level four. After adjusting the displacement method, the equilibrium level after displacement, based on an L value of 0.45, was determined to be level two. In this embodiment, the degree of displacement equilibrium was graded according to the Lorentz coefficient to determine the effect of heterogeneous composite displacement; the larger the Lorentz coefficient, the more severe the crossflow, and vice versa.

[0096] The method for evaluating the effect of heterogeneous composite drive also includes S5, drive adjustment effect evaluation, which is judged based on the ratio M of the Lorentz coefficient before and after drive adjustment. The main judgment levels are as follows:

[0097] M<1: Poor performance;

[0098] 1≤M<2: Moderate effect;

[0099] 2≤M<3: Good results;

[0100] M≥3: Good effect.

[0101] Based on the values ​​of the Lorentz coefficient before and after the drive adjustment, M = 0.80 / 0.45 = 1.78, indicating that the drive adjustment effect is moderate.

[0102] like Figure 3 As shown, in step S3, the specific calculation method for the Lorentz coefficient L of the well group before and after the adjustment and drive is as follows:

[0103] The n drag coefficient values ​​C obtained before and after the drive adjustment are sorted in ascending order to obtain a new sequence. The cumulative drag coefficient ratio S is then calculated according to the formula. i Cumulative well ratio T i .

[0104] Then, using the cumulative well ratio T i The x-axis represents the cumulative drag coefficient S. i Using the ordinate as the vertical axis, plot the Lorentz curve. Specifically, plot a series of points (T1, S1), (T2, S2), ..., (T...) in a Cartesian coordinate system. n ,S n Then, these points are connected sequentially to obtain the Lorentz curve.

[0105] Calculate the area A between the Lorentz curve and the absolute equilibrium line y=x, and the area B of the triangle below the absolute equilibrium line. In this embodiment, B=0.5, which is used to determine the Lorentz coefficient L.

[0106] The formulas for the cumulative resistance coefficient ratio, the cumulative well-to-well ratio, and the Lorentz coefficient are as follows:

[0107]

[0108]

[0109]

[0110] In the formula, C i C j All are resistance coefficients, calculated from the formula corresponding to the resistance coefficient C. i and j are subscripts, representing the permutation numbers corresponding to the resistance coefficient C, where j ≤ i. For example, C1 = represents the resistance coefficient between the first injection end and the extraction end; S i T represents the cumulative drag coefficient ratio; i is the cumulative well-to-well ratio; L is the Lorentz coefficient; n is related to the number of injection points and production points, and adjacent injection points and production points generate a resistance coefficient value.

[0111] In step S1, production dynamic data before and after the drive adjustment are collected at a frequency of 5 to 30 minutes / time, with equal time series.

[0112] In step S4, the effectiveness is verified by monitoring the decrease in maximum internal water cut and the increase in recovery rate after the adjustment. The specific criteria are: the decrease in maximum internal water cut Δfw ≥ 5%; the increase in recovery rate ΔEOR ≥ 3%. Meeting these criteria indicates that the adjustment effect has met the requirements.

[0113] The basic implementation process of the heterogeneous composite flooding effect evaluation method of the present invention includes: one injection end corresponds to multiple production ends, and the resistance coefficient refers to the value between any pair of injection and production ends.

[0114] ① Calculate the resistance coefficient C between the two wells based on the baseline injection volume and actual injection rate at each injection end, the production rate at the corresponding production end, and the injection-production pressure difference.

[0115] ② The resistance coefficient C between all the above well pairs j Arranged in ascending order. Calculate the cumulative drag coefficient ratio S i Cumulative well ratio T i .

[0116] ③Then according to S i and T i Calculate the Lorentz coefficient L of the well group.

[0117] ④ The Lorentz coefficient L is classified according to the degree of displacement equilibrium.

[0118] ⑤ The effect of displacement is evaluated based on the ratio of the Lorentz coefficient before and after displacement.

[0119] The injection rate before the injection end is adjusted and the production rate at the production end are collected and read using an equal time series method. The injection rate at each injection end and the production rate at the production end are read after the adjustment and the injection-production pressure difference is read before and after the adjustment.

[0120] The parts not described in detail above are common knowledge to those skilled in the art. This invention is not limited to the above-described preferred embodiments. Anyone should know that structural changes made under the guidance of this invention, and any technical solutions that are the same as or similar to this invention, fall within the protection scope of this invention.

Claims

1. A method for evaluating the effect of heterogeneous composite flooding, characterized in that, Includes the following steps: S1. Collection of well group data Production dynamics data at both injection and production ends in the well group before and after the adjustment and drive were collected using equal time series. S2. Calculate the drag coefficients before and after drive adjustment. The formula for calculating the resistance coefficient between the injection end and the extraction end is as follows: ； In the formula, P1 is the pressure at the injection end (Pa); P2 is the pressure at the extraction end (Pa); and Q1 is the injection velocity at the injection end (m). 3 / s; Q2 is the production rate at the extraction end, m 3 / s; Based on the production dynamic data of both injection and production ends before the adjustment and drive, read the injection rate at the injection end before the adjustment and drive, the production rate at the production end, read the pressure at both injection and production ends before the adjustment and drive, and calculate the resistance coefficient between each injection end and production end before the adjustment and drive. Based on the production dynamic data of the injection and production ends after adjustment, the injection rate of each injection end and the production rate of each production end after adjustment are read, the pressure of each injection and production end after adjustment are read, and the resistance coefficient between each injection end and production end after adjustment is calculated. S3. Calculate the Lorentz coefficient of the well group before and after the drive adjustment. Based on the resistance coefficients between the injection and production ends before and after the adjustment, the Lorentz coefficient L of the well group before and after the adjustment is calculated respectively. S4. Determine the displacement balance level. The degree of displacement equilibrium is determined by the Lorentz coefficient L, and the levels are classified as follows: L<0.3: First-order equilibrium; 0.3≤L<0.5: Second-order equilibrium; 0.5≤L<0.7: Three-level equilibrium; 0.7≤L≤1: Level 4 equilibrium; Adjust the drive scheme according to the balance level.

2. The method for evaluating the effect of heterogeneous composite flooding according to claim 1, characterized in that: It also includes S5, drive adjustment effect evaluation, which is judged based on the ratio M of the Lorentz coefficient before drive adjustment to the Lorentz coefficient after drive adjustment. The main judgment levels are as follows: M < 1: Poor results; 1≤M<2: Moderate effect; 2≤M<3: Good results; M≥3: Good effect.

3. The method for evaluating the effect of heterogeneous composite flooding according to claim 1, characterized in that: In step S4, the adjustment of the drive scheme according to the balance level is specifically as follows: When the level is Level 1 Balance, no adjustment is required. When the level is two-stage equalization, polymer-modulated drive is used; When the level is three-level equilibrium, particles are used for sealing and regulation. When the equilibrium level is four, the combined chemical agent and particle regulation are used.

4. The method for evaluating the effect of heterogeneous composite flooding according to claim 1, characterized in that, In step S3, the specific calculation method for the Lorentz coefficient L of the well group before and after the adjustment and drive is as follows: The n drag coefficient values ​​C obtained before and after the drive adjustment are sorted in ascending order to obtain a new sequence. The cumulative drag coefficient ratio S is then calculated according to the formula. i Cumulative well ratio T i ; Then, using the cumulative well ratio T i The x-axis represents the cumulative drag coefficient S. i Plot the Lorentz curve with the vertical axis as the ordinate; Calculate the area A between the Lorentz curve and the absolute equilibrium line y=x, and the area B of the triangle below the absolute equilibrium line, to determine the Lorentz coefficient L. The formulas for the cumulative resistance coefficient ratio, the cumulative well-to-well ratio, and the Lorentz coefficient are as follows: In the formula, C i C j All are drag coefficients, calculated from the formula corresponding to drag coefficient C. i and j are subscripts, representing the sequence number of the drag coefficient C, where j≤i; Si is the cumulative drag coefficient ratio. T i is the cumulative well-to-well ratio; L is the Lorentz coefficient; n is related to the number of injection points and production points, and adjacent injection points and production points generate a resistance coefficient value.

5. The method for evaluating the effect of heterogeneous composite flooding according to claim 1, characterized in that: In step S1, production dynamic data before and after the drive adjustment are collected at a frequency of 5 to 30 minutes / time, with equal time series.

6. The method for evaluating the effect of heterogeneous composite flooding according to claim 1, characterized in that: In step S4, the effect is verified by monitoring the decrease in maximum internal water cut and the increase in recovery rate after the adjustment.

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