A method and system for evaluating flow regulation effect of fracture-vug type reservoir

Abstract

The application discloses a method for evaluating flow regulation effect of fracture-vug type oil reservoirs, comprising the following steps: collecting dynamic single-well data of a well to be evaluated, determining each key parameter related to current flow regulation effect evaluation, and calculating actual evaluation coefficients of each key parameter; establishing a flow regulation effect evaluation coefficient network according to fracture-vug type oilfield development databases of different regions, wherein the evaluation coefficient network comprises evaluation standard coefficients of each key parameter under different evaluation grades; based on the flow regulation effect evaluation coefficient network and the actual evaluation coefficients of each key parameter, constructing a multivariate coefficient initial matrix, and using a grey correlation method to normalize the coefficients under different evaluation grades in the multivariate coefficient initial matrix, thereby forming a weighted matrix composed of comprehensive influence coefficients under each evaluation grade, so as to obtain single-well evaluation coefficients for representing the flow regulation effect of the well to be evaluated. The application can quantitatively evaluate the flow regulation effect of flow regulation channels of fracture-vug type oil reservoirs.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of flow regulation for fracture-cave reservoirs, and in particular to a method and system for evaluating the flow regulation effect of fracture-cave reservoirs. BACKGROUND

[0002] Fracture-cave carbonate reservoirs are a kind of special reservoirs, whose reservoir space is mainly fractures and caves, and the matrix part basically does not have the seepage capacity of fluid. The flow of fluid in the reservoir mainly depends on the communication between fractures and caves, caves and caves, and fractures and fractures. Due to the random distribution of fractures and caves, a good fracture-cave system is generally not formed, and therefore, the fracture-cave carbonate reservoir has very strong heterogeneity.

[0003] Similar to sandstone reservoirs, fracture-cave reservoirs usually use water injection construction to supplement formation energy, and water drive controls a large scale of reserves, with a high proportion, which is the main resource basis for long-term stable production. For example, in the Tahe oilfield, according to incomplete statistics, the water drive scale in the old area of the Tahe four and six areas gradually increases, and the controlled reserves at the end of 2019 are 81.75 million tons, accounting for 74% of the geological reserves. As shown in Figure 1 and Figure 2 , the water drive control reserves are the main resource basis for long-term stable production in the old area. After the water drive development of the fracture-cave reservoir, with the increase of the water drive control degree, the water drive control reserves are gradually increased. However, at this time, there is a problem that the part of the reserves controlled by water drive may not be completely developed, and often due to the strong heterogeneity of the fracture-cave reservoir, the water drive developed reserves are very low, such as the water drive undeveloped reserves in the Tahe four and six areas accounting for 52%, as shown in Figure 3 , and as shown in Figure 3 , most of the water drive controlled reserves are not developed. The main reason for this is that during the water drive process, the injected water does not displace along the ideal designed route, and often due to the development of underground fractures or fractures, the proportion of horizontal displacement is still low, and the plane water distribution is low.

[0004] From the geological background and fracture-cave structure of the fracture-cave reservoir, the injected water cannot effectively displace the oil, which mainly manifests in the following aspects: ①, the injected water flows into the bottom water along the fractures / dark rivers, the vertical sweep of the injected water is high (the ineffective volume of the injected water is large), the plane sweep is low, and the plane sweep efficiency is low; ②, when one injection and one production are used, the main channel of the injection and production well group is the dominant water flow channel, and water channeling is easy to occur, thereby causing the secondary channel not to be swept; ③, when one injection and multiple productions are used, the injected water channeling occurs along the dominant channel direction, and the inferior channel direction is not swept, which is similar to the one injection and one production case. In view of this, it is generally necessary to adjust the flow channel of the injected water to improve the plane sweep efficiency of the injected water and increase the plane water distribution. However, when the flow regulating agent is injected, the amount of the flow regulating agent is a problem to be solved.

[0005] Therefore, it is generally needed to adjust the flow channel of the injected water, improve the planar sweep efficiency of the injected water, and increase the planar water distribution. In view of the contradiction between the formation of the planar dominant water flow channel and the lack of the flow channel adjustment technology, the flow channel adjustment technology for the fractured-vuggy reservoir is a key technology for improving the water flooding recovery efficiency of the fractured-vuggy reservoir. The purpose of the flow channel adjustment is to control the dominant flow channel of the water flooding, so as to solve the problem of the invalid circulation of the injected water along the dominant flow channel, and further expand the swept volume of the water flooding. In the early stage of the flow channel adjustment test, many scholars mainly use the idea of water plugging and profile control in sandstone reservoirs, and conduct indoor experiments and field tests in a targeted manner, and confirm the effectiveness of the flow channel adjustment. However, after the flow channel adjustment, how to evaluate the effect of the flow channel adjustment quantitatively is a problem to be solved.

[0006] Therefore, the prior art needs to provide a flow channel adjustment effect evaluation scheme suitable for the fractured-vuggy reservoir to solve one or more of the above problems. SUMMARY

[0007] In order to solve the above technical problems, the present application provides a method for evaluating the flow channel adjustment effect of a fractured-vuggy reservoir, comprising: collecting dynamic single-well data of a well to be evaluated, determining each key parameter related to the current flow channel adjustment effect evaluation, and calculating the actual evaluation coefficient of each key parameter; establishing a flow channel adjustment effect evaluation coefficient network according to the development database of the fractured-vuggy reservoir in different regions, wherein the evaluation coefficient network includes the evaluation standard coefficient of each key parameter at different evaluation levels; based on the flow channel adjustment effect evaluation coefficient network and the actual evaluation coefficient of each key parameter, constructing a multivariate coefficient initial matrix, and using the grey correlation method to normalize the coefficients at different evaluation levels in the multivariate coefficient initial matrix to form a weighted matrix composed of comprehensive influence coefficients at each evaluation level, thereby obtaining a single-well evaluation coefficient for representing the flow channel adjustment effect of the well to be evaluated.

[0008] Preferably, the dynamic single-well data includes single-well basic parameters, dynamic production data, drilling data and logging data; the key parameters include natural decline rate, water cut, water distribution ratio, water drive fractured-vuggy reservoir control degree, water drive fractured-vuggy reservoir producing degree and pressure maintenance level.

[0009] Preferably, the dynamic production curve of the current well to be evaluated is obtained, the preset type C water drive characteristic curve is fitted by using the dynamic production curve, so as to determine the controlled reserves of the water drive fractured-vuggy reservoir, thereby calculating the slope of the fitted curve; the volume of the fractured-vuggy region associated with the current well to be evaluated is obtained, the actual evaluation coefficient of the water drive fractured-vuggy reservoir control degree is calculated by referring to the current fitted curve slope; the final producing degree of the current fractured-vuggy region is obtained, and based on this, the actual evaluation coefficient of the water drive fractured-vuggy reservoir producing degree is calculated according to the volume of the current fractured-vuggy region and the current fitted curve slope.

[0010] Preferably, the actual evaluation coefficient of the water drive fracture-cavern reservoir control degree and the actual evaluation coefficient of the water drive fracture-cavern reservoir producing degree are respectively calculated by using the following expressions:

[0011]

[0012]

[0013] wherein E c represents the actual evaluation coefficient of the water drive fracture-cavern reservoir control degree, E M represents the actual evaluation coefficient of the water drive fracture-cavern reservoir producing degree, k represents the current fitting curve slope, V represents the volume of the current fracture-cavern region, R gm represents the final producing degree of the current fracture-cavern region.

[0014] Preferably, a time step length is set, and the production time of the well to be evaluated is divided into a plurality of time-continuous time steps according to the step length; the natural decline rate change data, the water cut change data, and the water injection rate ratio change data in each time step are respectively calculated; the number of positive values, negative values, and zero values of each type of change data is counted, and the actual evaluation coefficient of the natural decline rate, the actual evaluation coefficient of the water cut, and the actual evaluation coefficient of the water injection rate ratio are respectively calculated according to the counting results.

[0015] Preferably, the actual evaluation coefficient of the pressure maintenance level is calculated according to the formation pressure of the well to be evaluated at the current production time and the original formation pressure, wherein the actual evaluation coefficient of the pressure maintenance level is calculated by using the following expression:

[0016]

[0017] wherein η represents the actual evaluation coefficient of the pressure maintenance level, p represents the current formation pressure, and p i represents the original formation pressure.

[0018] Preferably, the multi-element coefficient initial matrix is sequentially subjected to mean value operator calculation processing, processing of calculating the standard index absolute difference of the matrix, extreme value weighting amplification technology based on the absolute difference, and column element weighted normalization processing, so as to obtain the weighted matrix.

[0019] Preferably, the maximum membership degree principle is adopted to take the maximum comprehensive influence coefficient element in the weighted matrix as the single-well evaluation coefficient, and a preset grade coefficient evaluation standard network is used to determine the evaluation grade corresponding to the current single-well evaluation coefficient.

[0020] In another aspect, the present application also provides a system for evaluating the flow regulation effect of a fracture-vug reservoir, comprising: an actual evaluation coefficient calculation module configured to collect dynamic single-well data of a well to be evaluated, determine key parameters related to current flow regulation effect evaluation, and calculate actual evaluation coefficients of each key parameter; an evaluation standard coefficient establishment module configured to establish a flow regulation effect evaluation coefficient network based on a fracture-vug reservoir development database of different regions, the evaluation coefficient network comprising evaluation standard coefficients of each key parameter at different evaluation levels; and a single-well evaluation coefficient generation module configured to construct a multi-element coefficient initial matrix based on the flow regulation effect evaluation coefficient network and the actual evaluation coefficients of each key parameter, and adopt a grey correlation method to normalize the coefficients at different evaluation levels in the multi-element coefficient initial matrix to form a weighted matrix composed of comprehensive influence coefficients at each evaluation level, thereby obtaining a single-well evaluation coefficient used to represent the flow regulation effect of the well to be evaluated.

[0021] Preferably, the dynamic single-well data comprises single-well basic parameters, dynamic production data, drilling data and logging data; and the key parameters comprise a natural decline rate, a water cut, a water distribution ratio, a water drive fracture-vug reservoir control degree, a water drive fracture-vug reservoir producing degree and a pressure maintenance level.

[0022] Compared with the prior art, one or more embodiments of the above scheme can have the following advantages or beneficial effects:

[0023] The present application discloses a method and system for evaluating the flow regulation effect of a fracture-vug reservoir. The method and system comprehensively consider oil well dynamic and static data, and utilize a grey correlation method to calculate the correlation degree between actual evaluation effect coefficients and standard coefficient matrices, thereby converting the qualitative problem of oil well flow regulation channel effect evaluation into a quantitative problem. The method for evaluating the flow regulation channel of a fracture-vug reservoir in the present application can be applied to any period of fracture-vug reservoir development, and is not only suitable for single-well flow regulation channel evaluation of a fracture-vug reservoir, but also suitable for overall flow regulation channel evaluation of a well group and a unit. The present application quantitatively evaluates the suitability of a single-well flow regulation channel, converts the fracture-vug reservoir flow regulation channel evaluation problem from qualitative evaluation to quantitative comprehensive evaluation, has characteristics such as solid theoretical foundation, strong systematicness, simplicity, clear results, etc., not only overcomes the fuzziness and subjectivity of mutual comparison between parameters, but also simplifies the evaluation process, and practically and feasibly solves the problem of difficult well selection in a flow regulation channel. In addition, based on the quantitative single-well flow regulation channel comprehensive evaluation index, the present application can optimize the well selection standard of a fracture-vug reservoir flow regulation channel according to different stages of the flow regulation channel, further tap the remaining oil in a water drive development fracture-vug reservoir, improve the single-well reservoir producing degree, and better guide the actual production in a mine field.

[0024] In addition, the grey correlation method quantitative evaluation conclusion has certain guiding and practical value, can be used as the reference method of the flow channel of the single well and unit evaluation of the fracture-vug type reservoir, and can be popularized and used for the non-deterministic and subjective technical problems of the fracture-vug type reservoir development, such as the optimization evaluation of the conventional measures.

[0025] Other features and advantages of the present application will be set forth in the following description, and in part will become apparent to those skilled in the art upon examination of the following or can be learned by practice of the present application. The objects and other advantages of the present application can be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings. BRIEF DESCRIPTION OF DRAWINGS

[0026] The accompanying drawings are included to provide a further understanding of the present application and are incorporated in and constitute a part of the specification, illustrate embodiments of the present application and together with the description serve to explain the present application, but are not intended to limit the present application. In the drawings:

[0027] Figure 1 is a schematic diagram of the change of water drive controlled reserves of the existing Tahe oilfield old area Tahe four and six areas.

[0028] Figure 2 is a schematic diagram of the proportion of water drive controlled reserves of the existing Tahe oilfield old area Tahe four and six areas.

[0029] Figure 3 is a schematic diagram of the proportion of water drive unproduced reserves of the existing Tahe oilfield old area Tahe four and six areas.

[0030] Figure 4 is a step diagram of the method for evaluating the flow regulation effect of the fracture-vug type reservoir of the embodiment of the present application.

[0031] Figure 5 is a principle schematic diagram of the calculation process of the water distribution ratio in the method for evaluating the flow regulation effect of the fracture-vug type reservoir of the embodiment of the present application.

[0032] Figure 6 is a module block diagram of the system for evaluating the flow regulation effect of the fracture-vug type reservoir of the embodiment of the present application. DETAILED DESCRIPTION

[0033] The embodiments of the present application will be described in detail below with reference to the accompanying drawings and embodiments, so that how the present application applies technical means to solve technical problems and achieves technical effects can be fully understood and implemented. It should be noted that, as long as there is no conflict, each embodiment in the present application and each feature in each embodiment can be combined with each other, and the formed technical solutions are all within the protection scope of the present application.

[0034] Additionally, the steps shown in the flowcharts of the drawings can be performed in a computer system such as a set of computer-executable instructions. Also, while a logical sequence is shown in the flowcharts, in some instances, the steps shown or described can be performed in an order other than that shown.

[0035] Carbonate fracture-cave reservoir is a kind of special reservoir, whose reservoir space is mainly fracture and cave, and its matrix part basically has no seepage capacity of fluid. The fluid flow in the reservoir mainly depends on the communication between fracture and cave, cave and cave, and fracture and fracture. Due to the random distribution of fractures and caves, a good fracture-cave system is generally not formed, and therefore, the heterogeneity of carbonate fracture-cave reservoir is particularly strong.

[0036] Similar to sandstone reservoir, fracture-cave reservoir usually adopts water injection construction to supplement formation energy, and water drive controls a large scale of reserves, which is a major resource basis for long-term stable production. For example, according to incomplete statistics, the water drive scale in the old area of Tahe 4 and 6 areas of Tahe Oilfield is gradually increasing, and the controlled reserves at the end of 2019 are 81.75 million tons, accounting for 74% of the geological reserves. As shown in Figure 1 and Figure 2 , the water drive control reserves are the main resource basis for long-term stable production in the old area. After the water drive development of fracture-cave reservoir, with the increase of water drive control degree, the water drive control reserves are gradually increased. However, at this time, there is a problem that the part of reserves controlled by water drive may not be fully developed, and often due to the strong heterogeneity of fracture-cave reservoir, the water drive developed reserves are very low, such as the water drive undeveloped reserves in Tahe 4 and 6 areas accounting for 52%, as shown in Figure 3 . As shown in Figure 3 , most of the water drive controlled reserves are not developed. The main reason for this is that during the water drive process, the injected water does not displace along the ideal designed route, and often due to the development of underground fractures or fractures, the proportion of horizontal displacement is still low, and the plane water distribution is low.

[0037] From the geological background and fracture-cave structure of fracture-cave reservoir, the injected water cannot effectively displace the oil, which mainly manifests in the following aspects: ①, the injected water flows into the bottom water along the fracture / dark river, the vertical sweep of the injected water is high (the ineffective volume of the injected water is large), the plane sweep is low, and the plane sweep efficiency is low; ②, when injecting and producing, the main channel of the injection-production well group is the dominant water flow channel, which is easy to cause water channeling, and thus the secondary channel is not swept; ③, when injecting and producing, the injected water flows along the dominant channel direction, and the inferior channel direction is not swept, which is similar to the case of one injection and one production. In view of this, it is generally necessary to adjust the flow channel of the injected water to improve the plane sweep efficiency of the injected water and increase the plane water distribution. However, when injecting the flow adjusting agent, the amount of the flow adjusting agent is a problem to be solved.

[0038] Therefore, it is generally needed to adjust the flow channel of the injected water, improve the planar wave efficiency of the injected water, and increase the planar water distribution. In view of the contradiction between the formation of the planar dominant water flow channel and the lack of flow channel adjustment technology, the flow channel adjustment technology for the fractured-vuggy reservoir is a key technology for improving the water flooding recovery of the fractured-vuggy reservoir. The purpose of adjusting the flow channel is to control the dominant flow channel of the water flooding, so as to solve the problem of the invalid circulation of the injected water along the dominant flow channel, and then expand the water flooding swept volume. In the early stage of the flow channel adjustment test, many scholars mainly use the idea of water plugging and profile control of sandstone reservoirs, and carry out indoor experiments and field tests in a targeted manner, and confirm the effectiveness of the flow channel adjustment. However, after the flow channel adjustment, how is the effect and how to quantitatively evaluate the effect of the flow channel adjustment, which is a problem to be solved.

[0039] In the implementation of the present application, the inventors found in the research on domestic and foreign literatures that: for the flow channel adjustment related literatures of the fractured-vuggy reservoir, there are relatively few, and some scholars mainly introduce the flow channel identification method. There are relatively more literatures related to water plugging and profile control of sandstone reservoirs. By analogy to sandstone reservoirs, the flow channel adjustment technology of the fractured-vuggy reservoir can be equivalent to the water plugging and profile control technology of the sandstone reservoir. The existing evaluation technology of the water plugging and profile control of the sandstone reservoir mainly includes single factor evaluation and multi-factor evaluation, such as establishing the quantitative relationship between the wellhead pressure index of the profile control well, the water injection amount, the water injection pressure, the average water content of the corresponding oil well, the amount of plugging agent, and the profile control effect by the artificial neural network method, and predicting the water plugging and profile control model through the quantitative relationship model; by establishing the evaluation indexes of production dynamic data, monitoring data, water drive curve and economic benefit, and then introducing the optimal segmentation method, the profile control effect is divided into several grades. Relatively speaking, the water plugging and profile control evaluation method of the sandstone reservoir is relatively mature, but in the application aspect of the fractured-vuggy reservoir, these methods also have some problems, such as the suitability of the evaluation indexes and the evaluation method in the fractured-vuggy reservoir, which still needs to be further discussed.

[0040] In the implementation of the present application, the inventors found in the patent research at home and abroad that the prior art proposes a patent related to the evaluation of water drive development effect of fracture-vug reservoir. The application mainly maps each evaluation index on the radar chart based on the weight of each evaluation index, then establishes an evaluation function by using the perimeter and area, and obtains the influence of each parameter on the water drive development effect after normalization. Although the application can quantitatively evaluate the water drive development effect of fracture-vug reservoir, the biggest problem of the application is the determination of the weight value of the development index at different levels. The application simply considers that the weight of the development index at the same level is the same, and the weight of the four levels in the application is also the same, which is seriously inconsistent with the actual situation. For example, the pressure maintenance level, natural decline rate, water cut rising rate and cumulative injection-production ratio of dynamic effect index, the application considers that the weight of the four parameters is the same, i.e. 0.25, but in fact, a reasonable cumulative injection-production ratio can obtain a higher pressure maintenance level, and then the water cut rising rate is controlled, and the natural decline rate is naturally reduced. Therefore, the four indexes have a logical relationship, and cannot be equal to one weight value.

[0041] Therefore, it is necessary to re-establish a scheme for evaluating the flow regulation effect of fracture-vug reservoir. In order to solve one or more of the above technical problems, the present application proposes a flow regulation channel flow regulation effect evaluation method and system suitable for fracture-vug reservoir. The method and system first determine the influence degree of each index at different levels on the flow regulation channel effect, and distinguish different types of indexes in a targeted manner. At the same time, since there are differences in index changes at different times and different stages, in order to facilitate analysis, the application divides the evaluation period into multiple evaluation segments, then calculates the actual change of the index of each evaluation segment in turn, calculates the index value of each evaluation segment by establishing the calculation method of each evaluation index, and finally uses the grey correlation theory to quantitatively evaluate the flow regulation channel effect. In this way, the flow regulation effect evaluation method provided by the present application not only overcomes the fuzziness of mutual comparison between different types of key parameters and the limitations of subjective judgment of expert scoring, but also simplifies the evaluation process, and practically solves the technical problem of evaluating the flow regulation channel effect in the field, and has certain popularization value.

[0042] Figure 4 is the step diagram of the method for evaluating the flow regulation effect of fracture-vug reservoir according to the embodiments of the present application. The method for evaluating the flow regulation effect of fracture-vug reservoir (hereinafter referred to as "flow regulation effect evaluation method") according to the embodiments of the present application will be described below. Figure 4 The method for evaluating the flow regulation effect of fracture-vug reservoir (hereinafter referred to as "flow regulation effect evaluation method") according to the embodiments of the present application will be described below.

[0043] Step S410 collects the dynamic single-well data of the well to be evaluated, determines each key parameter related to the current flow regulation effect evaluation, and calculates the actual evaluation coefficient of each key parameter.

[0044] In step S410, firstly, dynamic single-well data of the well to be evaluated (data types of the dynamic single-well data are shown in Tables 3, 4 and 5 below) need to be collected. The dynamic single-well data include, but are not limited to, single-well basic parameters, dynamic production data, drilling data and logging data, etc. More specifically, the dynamic single-well data include information such as dynamic water injection rate, dynamic oil production rate, dynamic fluid production rate, dynamic water production rate, oil pressure and casing pressure of the recovery well, original saturation pressure, original reservoir pressure, formation water density, formation water viscosity, crude oil density, formation crude oil viscosity, permeability of filled solution cave, fracture permeability, etc.

[0045] Then, according to the collected dynamic single-well data of the current well to be evaluated, each key parameter related to the flow regulation effect evaluation is determined, and the actual evaluation coefficient (index) of each key parameter is calculated. In the embodiment of the present application, the key parameters at least include natural decline rate, water cut, water distribution ratio, water drive fracture-cave reservoir control degree, water drive fracture-cave reservoir producing degree and pressure maintenance level.

[0046] In the embodiment of the present application, not only the actual parameter values of each key parameter in different time periods are calculated by step S410, but also the actual evaluation coefficient of each key parameter is calculated by using the calculation model of the evaluation index of each key parameter which is constructed in advance, so as to use the actual evaluation coefficient to represent the influence degree of the actual value of the parameter on the flow regulation effect of the flow regulation channel, and to quantitatively represent the influence degree.

[0047] When calculating the actual evaluation coefficient of each key parameter, the following steps need to be implemented: firstly, set a time step length, and divide the production time of the well to be evaluated into several time-continuous time steps according to the set time step length; then, calculate the natural decline rate change data, the water cut change data and the water distribution ratio change data in each time step; finally, count the number of positive values, negative values and zero values of each type of change data (i.e. according to the natural decline rate change data corresponding to each time step, count the number of positive values, negative values and zero values of the change data; according to the water cut change data corresponding to each time step, count the number of positive values, negative values and zero values of the change data; according to the water distribution ratio change data corresponding to each time step, count the number of positive values, negative values and zero values of the change data), and calculate the actual evaluation coefficient of the natural decline rate, the actual evaluation coefficient of the water cut and the actual evaluation coefficient of the water distribution ratio according to the counting results.

[0048] First, the calculation process of the actual evaluation coefficient of the natural decline rate is described. After setting the step length of the time step, the production time of the well to be evaluated is divided into several time-continuous time steps according to the set step length, and the natural decline rate change data in each time step is calculated, thereby obtaining the corresponding actual evaluation coefficient.

[0049] The natural decline rate refers to the production decline rate without new well production and various stimulation measures. The natural decline rate is expressed by the following expression:

[0050]

[0051] wherein D represents the natural decline rate, Q i-1 and Q i represent the total production corresponding to the i-1th time step and the ith time step, respectively, Q x and Q c represent the new well cumulative production and the total stimulated oil production corresponding to the current time step (relative to the previous time step). Further, the change of the natural decline rate is defined as ΔD, and the natural decline rate change data corresponding to the current time step is calculated by the following expression:

[0052] ΔD = D actual -D ideal (2)

[0053] wherein ΔD represents the change of the natural decline rate corresponding to the current time step, D actual represents the actual decline rate of the natural decline rate corresponding to the current time step, and D ideal represents the ideal decline rate of the natural decline rate corresponding to the current time step.

[0054] Further, the actual evaluation coefficient R of the natural decline rate corresponding to the current time step is calculated by the following expression:

[0055]

[0056]

[0057]

[0058] wherein R represents the actual evaluation coefficient of the natural decline rate corresponding to the current time step, ΔD i represents the change of the natural decline rate corresponding to the ith time step, M represents the number of time steps in which the statistical natural decline rate change data is greater than zero (ΔD i >0), and N represents the number of time steps in which the statistical natural decline rate change data is less than zero (ΔD ithe number of time steps in which the statistical natural decline rate change data of each time step is greater than zero (ΔD i the number of time steps in which the statistical natural decline rate change data of each time step is equal to zero (ΔD

[0059] Then, the calculation process of the actual evaluation coefficient of the water cut is described. After the step length of the time step is set, the production time of the well to be evaluated is divided into several time-continuous time steps according to the set step length, and the water cut change data of the well in each time step is calculated respectively, so as to obtain the corresponding actual evaluation coefficient.

[0060] Further, the definition of the water cut change is expressed by the following expression:

[0061] Δf = f actual -f ideal (6)

[0062] wherein Δf represents the change of the corresponding water cut in the current time step, f actual represents the actual water cut corresponding to the current time step, and f ideal represents the ideal water cut corresponding to the current time step.

[0063] Further, the actual evaluation coefficient F of the water cut corresponding to the current time step is calculated by the following expression:

[0064]

[0065]

[0066]

[0067] wherein F represents the actual evaluation coefficient of the water cut corresponding to the current time step, Δf i represents the change of the water cut corresponding to the i-th time step, A represents the number of time steps in which the statistical water cut change data of each time step is greater than zero (Δf i >0), B represents the number of time steps in which the statistical water cut change data of each time step is less than zero (Δf i <0), and C represents the number of time steps in which the statistical water cut change data of each time step is equal to zero (Δf i =0). It can be seen from the above expressions (7)-(9) that the smaller the value of the evaluation coefficient F of the water cut is, the better the flow regulation effect of the flow regulation channel is; otherwise, the flow regulation effect is worse.

[0068] Next, the calculation process of the actual evaluation coefficient of the water distribution ratio is explained. After setting the step size of the time step, the production time of the well to be evaluated is divided into several consecutive time steps according to the set step size, and the change data of the water distribution ratio in each time step is calculated to obtain the corresponding actual evaluation coefficient.

[0069] Figure 5 This is a schematic diagram illustrating the principle of the water distribution ratio calculation process in the method for evaluating the flow regulation effect of fractured-vuggy reservoirs according to an embodiment of this application. The water distribution ratio refers to the ratio of water injection volume from a single-direction effective well (the well to be evaluated) to the total water injection volume. Figure 5 The principle followed in the calculation of the water distribution ratio is demonstrated. For a well under study, the water distribution in different directions is equal to the sum of the water distribution in each plane direction and the vertical water distribution. The water distribution in each plane direction is the production volume corresponding to the increase in production and pressure of the well under study. Specifically, the water distribution ratio data corresponding to each time step is calculated using the following expressions (10) to (12). The difference between the water distribution ratio in the current time step and the water distribution ratio in the previous time step is used to represent the change in the water distribution ratio corresponding to the current time step.

[0070] Furthermore, expressions (10) to (12) are shown below:

[0071] W x =N px +W px +V px B ox C t ΔP+Wh (10)

[0072]

[0073] N px +W px =∑(P j -P x )T xj (12)

[0074] Where x represents the well number to be evaluated; W x P represents the water distribution ratio of well x to be evaluated (effective well) within the current time step; x P represents the reservoir pressure of well x (the affected well) in the current time step, in MPa; j Indicates the injection pressure of injection well j in the current time step, in MPa; ΔP represents the production pressure differential in the current time step, in MPa; n is the total number of effective wells in the production well group; N px W represents the cumulative oil production of the affected well x in stages, in tons (t). piWx represents the stage cumulative water production of the well to be evaluated (the response well) x in the current time step, in t; inx Wx represents the stage cumulative water production of the well to be evaluated (the response well) x in the current time step, in t; px Vx,j represents the control volume between the corresponding response well x and the injection well j in the current time step, in m 3 ;T xj Bx,j represents the comprehensive transmissibility between the corresponding response well x and the injection well j in the current time step; ox Cx represents the volume coefficient of the well x; t B represents the comprehensive compressibility of the rock.

[0075] Further, the definition of the water production ratio change is represented by the following expression:

[0076] ΔE = E actual -E ideal (13)

[0077] where ΔE represents the change of the corresponding water production ratio in the current time step, E actual represents the corresponding actual water production ratio in the current time step, E ideal represents the corresponding ideal water production ratio in the current time step.

[0078] Further, the actual evaluation coefficient E of the corresponding water production ratio in the current time step is calculated by the following expression:

[0079]

[0080]

[0081]

[0082] where E represents the actual evaluation coefficient of the corresponding water production ratio in the current time step, ΔE i represents the change of the corresponding water production ratio in the i-th time step, J represents the number of time steps in which the change data of the water production ratio in each time step is greater than zero (ΔE i >0) obtained by statistics, I represents the number of time steps in which the change data of the water production ratio in each time step is less than zero (ΔE i <0) obtained by statistics, and H represents the number of time steps in which the change data of the water production ratio in each time step is equal to zero (ΔE i =0) obtained by statistics. As can be seen from the above expression (10) to expression (16), the greater the value of the evaluation coefficient F of the water production ratio, the better the flow regulation effect of the flow regulation channel; otherwise, the flow regulation effect is worse.

[0083] Next, the calculation process of the actual evaluation coefficient of the water drive fracture reservoir control degree and the actual evaluation coefficient of the water drive fracture reservoir producing degree is described.

[0084] Specifically, the water drive fracture control reserves are defined as the part of the reserves affected by the water drive pressure of the deployed well in the water drive development stage. That is, the water drive fracture control degree is represented as the ratio of the water drive fracture control reserves to the total fracture reserves of the entire oilfield recovery unit to which the well to be evaluated belongs. The water drive fracture producing reserves are defined as the part of the reserves occupied by the fracture units connected and forming injection-production correspondence of the deployed well in the water drive development stage. That is, the water drive fracture producing degree is represented as the ratio of the water drive fracture producing reserves to the total fracture reserves of the entire oilfield recovery unit to which the well to be evaluated belongs.

[0085] In practical application, it is difficult to calculate the water drive fracture control degree and the water drive fracture producing degree only from the definition. Therefore, the application determines the water drive fracture control reserves based on the production dynamic curve and the type C water drive characteristic curve, and then gives the calculation method of the water drive fracture control degree and the water drive fracture producing degree based on the fracture carving. Specifically, in the first step, the dynamic production curve of the current well to be evaluated is obtained, and the dynamic production curve is fitted with the preset type C water drive characteristic curve, so as to calculate the slope of the fitting curve, so as to determine the water drive fracture control reserves (to determine the fracture volume of the associated connected well group after water injection). In the second step, the volume of the fracture area associated with the current well to be evaluated is obtained, and the actual evaluation coefficient of the water drive fracture control degree is calculated by referring to the slope of the fitting curve calculated in the first step. The actual evaluation coefficient of the water drive fracture control degree is calculated by using the following expression:

[0086]

[0087] wherein E c represents the actual evaluation coefficient of the water drive fracture control degree, k represents the slope of the fitting curve, and V represents the total unit fracture volume corresponding to the entire oilfield injection-production well group to which the current well to be evaluated belongs. Then, in the third step, the final producing degree of the current fracture area is obtained, and based on this, the actual evaluation coefficient of the water drive fracture producing degree is calculated according to the volume of the current fracture area and the current slope of the fitting curve. The actual evaluation coefficient of the water drive fracture producing degree is calculated by using the following expression:

[0088]

[0089] wherein E M represents the actual evaluation coefficient of the water drive fracture producing degree, and R gmThe pressure maintenance level is an index for quantifying the rationality of the formation pressure relative to the recovery rate of the current well to be evaluated. Under a certain formation pressure level, the demand for water injection and the demand for liquid discharge can be met, and thus the formation pressure at this time belongs to the rational pressure maintenance level.

[0090] Finally, the calculation process of the actual evaluation coefficient of the pressure maintenance level is described.

[0091] In actual application, reasonable formation pressure can not only improve the recovery rate, but also reduce the difficulty of water injection. When the formation pressure is too low, although it is easy to inject water, it is easy to cause the defect of rapid pressure rise. Even if water injection continues, the recovery rate will not be improved, but the injection cost will be increased. Therefore, reasonable formation pressure is particularly important. Specifically, the pressure maintenance level refers to an index for quantifying the rationality of the formation pressure relative to the recovery rate of the current well to be evaluated. Under a certain formation pressure level, the demand for water injection and the demand for liquid discharge can be met, and thus the formation pressure at this time belongs to the rational pressure maintenance level.

[0092] In the process of calculating the actual evaluation coefficient of the pressure maintenance level, specifically, the actual evaluation coefficient of the pressure maintenance level corresponding to the current production time is calculated according to the formation pressure corresponding to the current production time of the well to be evaluated and the original formation pressure. Further, the actual evaluation coefficient of the pressure maintenance level is calculated by using the following expression:

[0093]

[0094] wherein η represents the actual evaluation coefficient of the pressure maintenance level of the well to be evaluated in the current time step, p represents the real-time formation pressure (the actual pressure of the current formation) in the current time step, p i represents the original formation pressure.

[0095] In this way, the actual evaluation index (actual evaluation coefficient) of each key parameter of the time step corresponding to the current production time is calculated by using the above step S410, and thus step S420 is entered.

[0096] Step S420 establishes a flow regulation effect evaluation coefficient network for the fractured-vuggy oil reservoir according to the fractured-vuggy oilfield development database of different regions. The flow regulation effect evaluation coefficient network includes evaluation standard coefficients of each key parameter at different evaluation levels. In the embodiment of the present application, the fractured-vuggy oilfield development database is a database for the development of fractured-vuggy oilfields, which is established based on historical production data of injection-production well groups of different fractured-vuggy reservoir regions, single-well basic parameters of injection wells or production wells at different positions, historical logging and drilling data, historical recording data and other information. In step S420, the influence of different types of key parameters on water flooding development effect is counted based on the fractured-vuggy oilfield development database, and the statistical eigenvalue data column is used as the fractured-vuggy reservoir flow regulation channel (water flooding development) evaluation coefficient network, so that the evaluation standard coefficients of each key parameter at different (flow regulation effect) evaluation levels are analyzed, and thus the flow regulation effect evaluation coefficient network for the fractured-vuggy reservoir is constructed.

[0097] In the embodiment of the present application, the fractured-vuggy reservoir flow regulation channel effect evaluation index is generated for the six types of key parameters of the present application, and the evaluation levels are divided into five levels, namely good, better, medium, worse and poor, as shown in Table 1.

[0098] Table 1 Flow regulation effect evaluation coefficient network

[0099] Evaluation parameter Good Better Medium Worse Bad Natural decline rate evaluation coefficient 0 2.5 7.5 12.5 17.5 Water cut evaluation coefficient -0.5 0.5 1.0 1.5 2.0 Water yield ratio evaluation coefficient 0.05 0.15 0.25 0.55 0.75 Water drive fractured-vug reservoir control degree, % 90 80 70 50 40 Water drive fractured-vug reservoir producing degree, % 80 70 60 40 30 Pressure maintenance level, % 95 90 80 70 50

[0100] After the construction of the flow regulation effect evaluation coefficient network is completed, step S430 is entered. In step S430, based on the flow regulation effect evaluation coefficient network constructed in step S420 and the actual evaluation coefficients of each key parameter calculated in step S410, a multivariate coefficient initial matrix is constructed, and the multivariate coefficients at different evaluation levels in the multivariate coefficient initial matrix are normalized by using the grey correlation method to form a weighted matrix composed of comprehensive influence coefficients at each evaluation level, so that a single-well evaluation coefficient for representing the flow regulation effect of the well to be evaluated is obtained.

[0101] In step S430, first (step S1301, not shown) the flow regulation effect evaluation coefficient network constructed in step S420 and the actual evaluation coefficients of each key parameter calculated in step S410 are used to construct a multivariate coefficient initial matrix. Specifically, a grey multivariate analysis processing matrix is established based on the actual evaluation coefficient calculation results of the actual six key parameters. The multivariate coefficient initial matrix is represented by the following expression:

[0102]

[0103] wherein x 11 , x 12 , x 13 , x 14, x 15 , x 16 respectively represent the actual evaluation coefficient calculation results of each key parameter, and P(l) represents the initial matrix of the multiple coefficients.

[0104] After obtaining the initial matrix of the multiple coefficients, the coefficients under different evaluation levels in the obtained initial matrix of the multiple coefficients are normalized to form a weighted matrix composed of the comprehensive influence coefficients under each evaluation level. In the process of generating the weighted matrix, the current obtained initial matrix of the multiple coefficients is sequentially subjected to mean value operator calculation processing, processing of calculating the standard index absolute difference of the matrix, extreme value weighting amplification technology based on the absolute difference, and column element weighted normalization processing to obtain the weighted matrix. In the embodiment of the present application, the weighted matrix is composed of the comprehensive influence coefficients under each evaluation level. When calculating the comprehensive influence coefficients under each evaluation level, the multiple coefficient elements corresponding to the respective evaluation levels in the initial matrix of the multiple coefficients need to be normalized.

[0105] Firstly, the initial matrix P(l) of the multiple coefficients is processed by using the mean value operator to obtain a matrix P(2) representing the calculation result of the mean value operator. The calculation steps of the mean value operator are as follows: first, the row data in the matrix P(l) in the above step is taken as a new data column, denoted as X i =(x i (1), x i (2), x i (3), x i (4), x i (5), x i (6)), wherein i represents the row number (i.e., represents the evaluation level of different levels); then the homogenized new data column is denoted as X i '=(x i '(1), x i '(2), x i '(3), x i '(4), x i '(5), x i '(6)), wherein, k represents the serial number of different types of key parameters.

[0106] Then, the key parameter data in the matrix P(2) is subjected to comprehensive analysis processing. That is, the calculation of the standard index absolute difference and the extreme value weighting amplification technology based on the absolute difference are sequentially used to calculate the gray multiple weighted coefficients. The gray multiple weighted coefficients are calculated by using the following expression:

[0107]

[0108] Δ i(k) = |X0(k) - X i (k) (22)

[0109] wherein, X0(k) represents the parameter type standard value corresponding to each item of key parameter data, respectively represent the minimum difference and the maximum difference of the two levels of standard index, A is the grey resolution coefficient. Thus, by using the transformation processing of the above expression (21) and expression (22), the grey weighting coefficient sequence P i (k) is obtained, that is, the grey weighting coefficient sequence is represented by the following expression:

[0110] P i (k) = (P i (1), P i (2), P i (3), P i (4), P i (5)) (23)

[0111] Thus, by using each grey weighting coefficient sequence formed by expression (23), a matrix is constructed to represent the extreme value weighting amplification technology based on the absolute difference.

[0112] Finally, due to the large number of coefficients and the excessive dispersion of information, it is not convenient to optimize. The comprehensive normalization technology is adopted to calculate the weight value corresponding to each type of key parameter, so as to concentrate the coefficients of each point key parameter under the same evaluation level into a coefficient value according to the weight value corresponding to different key parameters, thereby obtaining the comprehensive influence coefficient corresponding to each evaluation level. Among them, the comprehensive influence coefficient under each evaluation level is calculated by using the following expression:

[0113]

[0114] wherein, P i represents the comprehensive influence coefficient under the i-th evaluation level, Y0(k) represents the weight value corresponding to the k-th type of key parameter, which is calculated by using the following expression:

[0115]

[0116] In this way, the present application converts the multivariate coefficient initial matrix into a weighted matrix composed of comprehensive influence coefficients under each evaluation grade by using the grey correlation method, not only considers the cumulative actual evaluation coefficients (representing the actual influence degree of various key parameters on the persistence of flow regulation effect after flow regulation) of each key parameter in the whole production stage, but also calculates the quantitative correlation degree of the actual evaluation coefficients of different key parameters and the evaluation standard coefficients of different grades in the fracture-cave type oilfield development evaluation standard. Therefore, the embodiment of the present application can (step S4303, not shown) compare the comprehensive influence coefficients of each grade in the weighted matrix with the preset grade coefficient evaluation standard network, compare each comprehensive influence coefficient with the corresponding grade standard coefficient in the grade coefficient evaluation standard network, and take the evaluation grade with the highest closeness degree as the quantitative evaluation result of the flow regulation effect of the current well to be evaluated.

[0117] Specifically, (step S4303, not shown) the maximum comprehensive influence coefficient element in the weighted matrix is taken as the single-well evaluation coefficient by using the maximum membership degree principle, and the evaluation grade corresponding to the current single-well evaluation coefficient is determined by using the preset grade coefficient evaluation standard network (see Table 2 below).

[0118] In the embodiment of the present application, the grade coefficient evaluation standard network of different flow regulation effect evaluation grades is preset, including the standard threshold corresponding to different flow regulation effect evaluation grades, so as to divide the flow regulation effect into grades by using different standard thresholds, thereby converting the actually obtained single-well evaluation coefficient into the flow regulation evaluation grade.

[0119] Table 2 Grade coefficient evaluation standard network

[0120] Evaluation parameter Good Better Medium Worse Bad Gray comprehensive evaluation value 0.85 0.7 0.5 0.35 0.15

[0121] For example, the flow regulation effect evaluation method described in the embodiment of the present application is applied to M1 well in a certain fracture-cave type reservoir area, and the specific implementation process is as follows:

[0122] (1) First, the production dynamic data of the target evaluation well are collected, as shown in Tables 3, 4 and 5, and the following takes M1 well as an example to explain the present application in detail.

[0123] Table 3 M1 well dynamic production data one

[0124]

[0125]

[0126] Table 4 M1 well dynamic production data two

[0127]

[0128]

[0129] Table 5 M1 well dynamic production data three

[0130] Parameter Value Parameter Value Original saturation pressure (MPa) 58 Original reservoir pressure (MPa) 58 Formation water density (g / cm 3 )]]> 1 Crude oil density (g / cm 3 )]]> 0.87 Formation water viscosity (mPa.s) 0.51 Formation crude oil viscosity (mPa.s) 0.61 Filling cave permeability (mD) 300 Fracture permeability (mD) 1000

[0131] (2), according to the calculation method of each key parameter actual evaluation index in step (2), the natural decline rate evaluation coefficient, water cut evaluation coefficient, water yield ratio evaluation coefficient, water drive fracture reservoir control degree, water drive fracture reservoir producing degree and pressure retention level of M1 well are calculated as 4.3, -0.62, -0.03, 86%, 81% and 92.8%.

[0132] (3), using the method in step (4), the color multivariate analysis processing matrix is calculated

[0133]

[0134] After processing P(1) by using the mean operator, the following is obtained:

[0135]

[0136] Based on the standard index absolute difference method (i.e. after processing by expression 22), after processing P(2), the following is obtained:

[0137]

[0138] Using the extreme value weighted combination amplification technology of absolute difference (i.e. after processing by expression 21), after processing P(3), the following is obtained:

[0139]

[0140] (4), based on the comprehensive normalization method, the weighted matrix is obtained:

[0141] P(5) = (0.9024 0.8936 0.7742 0.6831 0.6092)

[0142] Using the maximum membership principle, the effect of flow regulating channel is evaluated, and the single well evaluation coefficient of M1 well is P = 0.9094.

[0143] Therefore, based on the grade coefficient evaluation standard network of table 2, the effect of the flow regulating channel of M1 well is very good.

[0144] On the other hand, based on the method for evaluating the flow regulating effect of the fracture-vug type reservoir described above, the embodiment of the present application further provides a system for evaluating the flow regulating effect of the fracture-vug type reservoir (hereinafter referred to as "flow regulating effect evaluation system"). Figure 6 is the module block diagram of the system for evaluating the flow regulating effect of the fracture-vug type reservoir according to the embodiment of the present application. As shown inFigure 6 The flow regulation effect evaluation system comprises at least an actual evaluation coefficient calculation module 61, an evaluation standard coefficient establishment module 62 and a single well evaluation coefficient generation module 63.

[0145] Specifically, the actual evaluation coefficient calculation module 61 is configured to collect dynamic single well data of the well to be evaluated, determine each key parameter related to the current flow regulation effect evaluation, and calculate the actual evaluation coefficient of each key parameter, according to the method described in step S410; the evaluation standard coefficient establishment module 62 is configured to establish a flow regulation effect evaluation coefficient network according to the fracture-cave type oilfield development database of different regions, the evaluation coefficient network comprising evaluation standard coefficients of each key parameter at different evaluation levels, according to the method described in step S420; and the single well evaluation coefficient generation module 63 is configured to construct a multivariate coefficient initial matrix based on the flow regulation effect evaluation coefficient network output by the evaluation standard coefficient establishment module 62 and the actual evaluation coefficient of each key parameter output by the actual evaluation coefficient calculation module 61, and adopt the grey correlation method to normalize the coefficients at different evaluation levels in the multivariate coefficient initial matrix to form a weighted matrix composed of comprehensive influence coefficients at each evaluation level, thereby obtaining the single well evaluation coefficient used to represent the flow regulation effect of the well to be evaluated.

[0146] The dynamic single well data comprises single well basic parameters, dynamic production data, drilling data and logging data. In addition, the key parameters comprise a natural decline rate, a water cut, a water distribution ratio, a water drive fracture-cave reservoir control degree, a water drive fracture-cave reservoir producing degree and a pressure maintenance level.

[0147] The application discloses a method and system for evaluating flow regulation effect of a fracture-vug type oil reservoir.

[0148] In addition, the quantitative evaluation conclusion of the grey correlation method has certain guiding property and practical value, and can be used as a reference method for evaluating the flow regulation channel of the fracture-vug type oil reservoir, and can be used for the optimization of the well selection standard of the flow regulation channel of the fracture-vug type oil reservoir according to different stages of the flow regulation channel, and further tapping the remaining oil in the fracture-vug type oil reservoir developed by water flooding, improving the producing degree of single well reserves, and better guiding the actual production in the mine field.

[0149] The above merely describes a preferred embodiment of the application, but the protection scope of the application is not limited to this. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed by the application, which should be covered by the protection scope of the application. Therefore, the protection scope of the application should be subject to the protection scope of the claims.

[0150] It should be understood that the embodiments disclosed by the application are not limited to the specific structure, processing steps or materials disclosed herein, but should extend to equivalent replacements of these features understood by those skilled in the relevant art. It should also be understood that the terms used herein are only for the purpose of describing the specific embodiments, and do not mean limitation.

[0151] The phrase "one embodiment" or "an embodiment" appearing in the specification means that the specific features, structures or characteristics described in connection with the embodiment are included in at least one embodiment of the application. Therefore, the phrase "one embodiment" or "an embodiment" appearing in various places in the specification does not necessarily mean the same embodiment.

[0152] Although the present application has been described with reference to the above embodiments, the contents described are only the embodiments adopted for facilitating the understanding of the present application, and are not intended to limit the present application. Any modification and change in the form and details of the present application can be made by any person skilled in the art without departing from the spirit and scope of the present application, and the patent protection scope of the present application shall be subject to the scope defined by the appended claims.

Claims

1. A method for evaluating the flow regulation effect of fractured-vuggy reservoirs, comprising: Collect dynamic single-well data of the wells to be evaluated, determine the key parameters related to the current flow regulation effect evaluation, and calculate the actual evaluation coefficient of each key parameter; Based on the development database of fractured-vuggy oilfields in different regions, an evaluation coefficient network for flow regulation effect is established. The evaluation coefficient network includes the evaluation standard coefficients of each key parameter under different evaluation levels. Based on the aforementioned flow regulation effect evaluation coefficient network and the actual evaluation coefficients of each key parameter, a multivariate coefficient initial matrix is ​​constructed. Then, using the grey relational analysis method, the coefficients under different evaluation levels in the multivariate coefficient initial matrix are normalized to form a weighted matrix composed of the comprehensive influence coefficients under each evaluation level. This yields the single-well evaluation coefficients used to characterize the flow regulation effect of the well to be evaluated. The key parameters include natural decline rate, water cut, water fractionation ratio, degree of control over water-driven fractured-vuggy reserves, degree of utilization of water-driven fractured-vuggy reserves, and pressure maintenance level. The water allocation ratio data corresponding to each time step is calculated using the following expression. The difference between the water allocation ratio in the current time step and the water allocation ratio in the previous time step is then used to represent the change in the water allocation ratio at the current time step and the corresponding actual evaluation coefficient: W x =N px +W px +V px B ox C t △P+Wh N px +W px =∑(P j -P x )T xj △E=E actual -AND ideal Where x represents the well number to be evaluated, W x P represents the water distribution ratio of well x to be evaluated within the current time step. x P represents the reservoir pressure of well x to be evaluated within the current time step. j Indicates the injection pressure of injection well j in the current time step, ΔP represents the production pressure differential in the current time step, n is the total number of effective wells in the production well group, and N is the total number of effective wells in the production well group. px W represents the cumulative oil production of well x under evaluation. px W represents the cumulative water production of well x in the current time step. inx V represents the cumulative water injection volume of well x to be evaluated within the current time step. px T represents the control volume between well x to be evaluated and injection well j within the current time step. xj B represents the combined conductivity between the well to be evaluated (x) and the injection well (j) within the current time step. ox C represents the volume factor of the evaluation well x. t E represents the overall compressibility coefficient of the rock, and ΔE represents the change in the water distribution ratio within the current time step. actual E represents the actual water distribution ratio within the current time step. ideal E represents the ideal water allocation ratio within the current time step, and E represents the actual evaluation coefficient of the water allocation ratio within the current time step. △E i Let J represent the change in the water distribution ratio within the i-th time step, J represent the number of time steps in which the change in the water distribution ratio is greater than zero, I represent the number of time steps in which the change in the water distribution ratio is less than zero, and H represent the number of time steps in which the change in the water distribution ratio is equal to zero. The actual evaluation coefficients for the degree of control over water-driven fractured cavern reserves and the actual evaluation coefficients for the degree of utilization of water-driven fractured cavern reserves are calculated using the following steps: The dynamic production curve of the current well to be evaluated is obtained, and the dynamic production curve is used to fit a preset type C water drive characteristic curve to determine the controlled reserves of water drive fractures and vulnerabilities, thereby calculating the slope of the fitted curve. Obtain the volume of the fractured cavity region associated with the current well to be evaluated, and calculate the actual evaluation coefficient of the water-drive fractured cavity reserve control degree by referring to the slope of the current fitted curve. The final recovery level of the current fractured cavity region is obtained. Based on this, the actual evaluation coefficient of the water-driven fractured cavity reserve utilization level is calculated according to the volume of the current fractured cavity region and the slope of the current fitted curve. The actual evaluation coefficients of the water-driven fractured cavity reserve control level and the actual evaluation coefficients of the water-driven fractured cavity reserve utilization level are calculated using the following expressions respectively: Among them, E c E represents the actual evaluation coefficient indicating the degree of control over the water-driven fractured cavity reserves. M The actual evaluation coefficient representing the degree of utilization of water-driven fractured-vuggy reserves, k represents the slope of the current fitted curve, V represents the total unit fractured-vuggy volume corresponding to the entire oilfield injection-production well group to which the current well to be evaluated belongs, and R gm This indicates the final extraction level of the current fractured area.

2. The method according to claim 1, characterized in that, The dynamic single-well data includes basic parameters of the single well, dynamic production data, drilling data, and logging data.

3. The method according to claim 2, characterized in that, Set the time step size, and divide the production time of the well to be evaluated into several time-continuous time steps according to the set step size; Calculate the natural decline rate, water content, and water fraction change data for each time step. The number of positive, negative, and zero values ​​for each type of change data is counted. Based on the statistical results, the actual evaluation coefficients of the natural decline rate, the moisture content, and the water separation ratio are calculated respectively.

4. The method according to claim 2, characterized in that, Based on the formation pressure of the well to be evaluated at the current production time and the original formation pressure, the actual evaluation coefficient of the pressure maintenance level is calculated, wherein the actual evaluation coefficient of the pressure maintenance level is calculated using the following expression: Where η represents the actual evaluation coefficient of the pressure maintenance level, p represents the current formation pressure, p i This represents the original formation pressure.

5. The method according to any one of claims 1 to 4, characterized in that, The weighted matrix is ​​obtained by sequentially performing mean-averaging, calculating the absolute difference of the standard index of the matrix, applying extreme value weighting amplification based on the absolute difference, and weighting and normalizing the column elements.

6. The method according to claim 5, characterized in that, Using the principle of maximum membership, the element with the largest comprehensive influence coefficient in the weighted matrix is ​​taken as the evaluation coefficient of the single well, and the evaluation level corresponding to the current evaluation coefficient is determined by using a preset grade coefficient evaluation standard network.

7. A system for evaluating the flow regulation effect of fractured-vuggy reservoirs, comprising: The actual evaluation coefficient calculation module is configured to collect dynamic single-well data of the well to be evaluated, determine the key parameters related to the current flow regulation effect evaluation, and calculate the actual evaluation coefficient of each key parameter. The evaluation standard coefficient establishment module is configured to establish a flow regulation effect evaluation coefficient network based on the development database of fractured-vuggy oilfields in different regions. The evaluation coefficient network includes the evaluation standard coefficient of each key parameter under different evaluation levels. The single-well evaluation coefficient generation module is configured to construct a multivariate coefficient initial matrix based on the flow regulation effect evaluation coefficient network and the actual evaluation coefficients of each key parameter. Then, using the grey relational analysis method, it normalizes the coefficients at different evaluation levels in the multivariate coefficient initial matrix, forming a weighted matrix composed of the comprehensive influence coefficients at each evaluation level. This yields the single-well evaluation coefficient used to characterize the flow regulation effect of the well to be evaluated. The key parameters include natural decline rate, water cut, water fractionation ratio, degree of control over water-driven fractured-vuggy reserves, degree of utilization of water-driven fractured-vuggy reserves, and pressure maintenance level. The water allocation ratio data corresponding to each time step is calculated using the following expression. The difference between the water allocation ratio in the current time step and the water allocation ratio in the previous time step is then used to represent the change in the water allocation ratio at the current time step and the corresponding actual evaluation coefficient: W x =N px +W px +V px B ox C t △P+Wh N px +W px =∑(P j -P x )T xj △E=E actual -AND ideal Where x represents the well number to be evaluated, W x P represents the water distribution ratio of well x to be evaluated within the current time step. x P represents the reservoir pressure of well x to be evaluated within the current time step. j Indicates the injection pressure of injection well j in the current time step, ΔP represents the production pressure differential in the current time step, n is the total number of effective wells in the production well group, and N is the total number of effective wells in the production well group. px W represents the cumulative oil production of well x under evaluation. px W represents the cumulative water production of well x in the current time step. inx V represents the cumulative water injection volume of well x to be evaluated within the current time step. px T represents the control volume between well x to be evaluated and injection well j within the current time step. xj B represents the combined conductivity between the well to be evaluated (x) and the injection well (j) within the current time step. ox C represents the volume factor of the evaluation well x. t E represents the overall compressibility coefficient of the rock, and ΔE represents the change in the water distribution ratio within the current time step. actual E represents the actual water distribution ratio within the current time step. ideal E represents the ideal water allocation ratio within the current time step, and E represents the actual evaluation coefficient of the water allocation ratio within the current time step. △E i Let J represent the change in the water distribution ratio within the i-th time step, J represent the number of time steps in which the change in the water distribution ratio is greater than zero, I represent the number of time steps in which the change in the water distribution ratio is less than zero, and H represent the number of time steps in which the change in the water distribution ratio is equal to zero. The actual evaluation coefficient calculation module is further configured to calculate the actual evaluation coefficient of the water-driven fractured cavity reserve control degree and the actual evaluation coefficient of the water-driven fractured cavity reserve utilization degree using the following steps respectively: The dynamic production curve of the current well to be evaluated is obtained, and the dynamic production curve is used to fit a preset type C water drive characteristic curve to determine the controlled reserves of water drive fractures and vulnerabilities, thereby calculating the slope of the fitted curve. Obtain the volume of the fractured cavity region associated with the current well to be evaluated, and calculate the actual evaluation coefficient of the water-drive fractured cavity reserve control degree by referring to the slope of the current fitted curve. The final recovery level of the current fractured cavity region is obtained. Based on this, the actual evaluation coefficient of the water-driven fractured cavity reserve utilization level is calculated according to the volume of the current fractured cavity region and the slope of the current fitted curve. The actual evaluation coefficients of the water-driven fractured cavity reserve control level and the actual evaluation coefficients of the water-driven fractured cavity reserve utilization level are calculated using the following expressions respectively: Among them, E c E represents the actual evaluation coefficient indicating the degree of control over the water-driven fractured cavity reserves. M The actual evaluation coefficient representing the degree of utilization of water-driven fractured-vuggy reserves, k represents the slope of the current fitted curve, V represents the total unit fractured-vuggy volume corresponding to the entire oilfield injection-production well group to which the current well to be evaluated belongs, and R gm This indicates the final extraction level of the current fractured area.

8. The system according to claim 7, characterized in that, The dynamic single-well data includes basic parameters of the single well, dynamic production data, drilling data, and logging data.

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