A method for evaluating the production enhancement effect of hydraulic jetting composite acidizing in open hole horizontal wells

Abstract

The invention discloses a method for evaluating the production increase effect of hydraulic jet composite acidizing of an open hole horizontal well, and relates to the field of oil and gas field development engineering. The method mainly comprises the steps of establishing a hydraulic jet composite acidizing model of an open hole horizontal well, calculating the effective development radius of a hydraulic jet composite acidizing wormhole, calculating a local skin coefficient of hydraulic jet composite acidizing, calculating an equivalent skin coefficient after hydraulic jet composite acidizing of a whole well section, and evaluating the composite acidizing effect based on a dimensionless production increase index, thereby eliminating the difficulty of transforming the whole well section of a horizontal well section and the limitation of insufficient penetration depth of an acid solution, so as to realize the production increase of acidizing of an open hole horizontal well of carbonate rock; by continuously comparing the skin coefficient and the dimensionless production increase index, the engineering parameters can be continuously optimized, the acidizing effect can be enhanced, and the composite acidizing can be made more economical to a maximum extent.

Description

Technical Field

[0001] The invention relates to the field of oil and gas field development engineering, and in particular to a method for evaluating the production increase effect of hydraulic jet composite acidification of an open hole horizontal well. Background Art

[0002] Open hole horizontal well completion is a commonly used completion method for carbonate reservoirs. It not only maximizes the release of the horizontal section's ability to control the oil leakage of the reservoir, but also saves the cost of horizontal section casing and cementing, and improves the development efficiency of the oil field. However, during the drilling and completion of horizontal wells, drilling fluid and completion fluid invade the open hole horizontal well section and damage the reservoir. The oil test results are often interpreted as a positive skin coefficient. This damage limits the production capacity of the oil well. Acidizing is an effective engineering means to remove near-wellbore pollution in carbonate reservoirs. For the completion of open hole horizontal wells in carbonate reservoirs, on the one hand, due to the difficulty of isolation, it is impossible to use the mechanical isolation and segmented acidizing method for unblocking; on the other hand, the horizontal well section is long. If the conventional vertical well acidizing design method is used, the scale of acid use is large, the on-site construction is difficult, the acid injection time is long, the cost is high, and the performance requirements of the acid system are high. At present, coiled tubing dragging acidizing is a commonly used unblocking method for open hole horizontal wells. The acid distribution is carried out by controlling the lifting speed of the coiled tubing and the injection speed of the acid to a certain extent, which promotes the uniform distribution of the acid. However, objective conditions such as long horizontal well sections, limited construction scale, and reservoir heterogeneity limit the full-well section transformation of horizontal well sections and the penetration depth of acid fluids, making it difficult to fully release the production capacity of horizontal wells and even more difficult to achieve the purpose of increasing production. Therefore, an economical and effective method for acidizing and increasing production in carbonate open-hole horizontal wells with deep penetration and full-well section transformation is needed to solve the above engineering problems. Summary of the invention

[0003] The purpose of the present invention is to remove the limitation of the whole well section transformation of the horizontal well section and the penetration depth of the acid fluid, so as to realize the high-efficiency acidizing and production increase of the carbonate open hole horizontal well.

[0004] The present invention is a method for evaluating the production enhancement effect of hydraulic jet composite acidizing in open hole horizontal wells, which mainly comprises the following steps:

[0005] S1. Establish a hydraulic jet composite acidizing model based on the actual size of the horizontal well;

[0006] S2. Calculate the effective development radius of the wormhole in the horizontal well according to the above hydraulic jet composite acidizing model;

[0007] S3. Calculate the local skin coefficient in the hydraulic jet composite acidification model according to the above hydraulic jet composite acidification model and the effective development radius of the wormhole;

[0008] S4. Calculate the equivalent skin coefficient of the entire well section after hydraulic jet composite acidizing based on the above local skin coefficient;

[0009] S5. Calculate the dimensionless increase index after acidizing based on the above equivalent skin coefficient and evaluate the effect of composite acidizing;

[0010] The open hole horizontal well hydraulic jet composite acidizing well model in step S1 is a top view of the horizontal well, including the horizontal well and the seepage control radius, and the jet holes and wormholes of each section of the horizontal well.

[0011] After determining these data, the relevant data are imported into the corresponding computer program to calculate the production increase effect of hydraulic jet composite acidizing in open hole horizontal wells in carbonate reservoirs. The production increase effect is continuously improved by continuously optimizing the engineering design parameters.

[0012] The upper end of the inner wall of the horizontal well is provided with a plurality of injection holes, and the horizontal well is divided into a plurality of sections with each injection hole as the center. The composite acidizing of the present invention using a continuous oil pipe to drag the injection tool can realize the production increase transformation of the entire section of the open hole horizontal well in a single construction, which greatly improves the effectiveness and economy of the construction.

[0013] Under the high-speed jet of the downhole jet tool, the acid will continuously erode and react the well wall rock to form a jet hole, and break through the reservoir pollution depth along the jet hole under the pressure squeeze action. After breaking through the inner wall of the jet hole, the acid spreads in a dendrite shape to form an acid wormhole. Sufficient jet and impact flow can promote the development of acid wormholes to the deep reservoir and increase the coverage of the acidizing effect. Moreover, while the acid is being sprayed, the acid that has not entered the jet hole will react with the surrounding open hole section to react with matrix acidification to remove surface pollution. The operating efficiency of this jet composite acidizing method is greatly affected by the number of jet sections and the jet flow rate. Therefore, the best production increase effect can be obtained through reasonable parameter design. According to the different acidizing effects and control areas, the area near the jet hole and other areas can be divided into jet acidizing areas and matrix acidizing areas. This hydraulic jet composite acidizing can not only remove the near-well pollution, but also achieve the purpose of increasing production through deep penetration of the acid wormhole.

[0014] The effective development radius of wormholes in the hydraulic jetting composite acidification model in step S2 represents the extent to which wormholes can spread during the hydraulic jetting composite acidification process, including the effective wormhole radius of jetting acidification and the effective wormhole radius of matrix acidification, wherein:

[0015] The calculation formula of the effective wormhole radius of the jet acidification is shown in formula (1): je =r j I a Formula (1);

[0016] The calculation formula of the effective wormhole radius of the matrix acidification is shown in formula (2): me =r m I a Formula (2);

[0017] In formula (1) and formula (2), r m The radius of radially developed wormholes designed for single-well matrix acidizing; r me I is the effective wormhole radius of matrix acidizing in a single well section under the condition of permeability anisotropy; a is the permeability anisotropy, representing the ability of fluid to flow in different directions, that is, the ability of wormhole development; r j The radius of the wormhole designed for single-section jet acidizing; r je It is the effective wormhole radius of single well section jet acidizing under the condition of permeability anisotropy.

[0018] In this step, the entire horizontal well section of the open hole well is first discretized into n single well sections with a length of Δx according to the model in step S1, and then the downhole jetting tool is dragged to perform composite acidizing on each single well section from the "toe" to the "root" of the horizontal well. After the acidizing of each section is completed, the jetting tool can be dragged to perform the acidizing composite jetting of the next section. The operation is simple and easy to apply, and the single-trip construction greatly improves the efficiency and economy of the operation.

[0019] In this step, the effective wormhole radius of the jet acidification and the effective wormhole radius of the matrix acidification are calculated based on the known radial development wormhole radius. If the existing radial development wormhole radius is simply used, the differential development of acid wormholes caused by formation anisotropy cannot be considered. a Calculations are performed to make the calculated data closer to the true value.

[0020] Here, the permeability anisotropy I a The calculation formula is shown in formula (3):

[0021] In formula (3), k H is the horizontal permeability of the reservoir; k V is the vertical permeability of the reservoir.

[0022] The calculation of the skin coefficient of the single well section hydraulic jet composite acidizing in step S3 mainly calculates the skin coefficient, that is, the seepage resistance coefficient of the near-well zone, which is a dimensionless coefficient indicating the degree of perfection of the well. Its size is affected by many factors such as working fluid invasion, perforation opening degree, acidizing, fracturing and non-Darcy seepage during the completion process.

[0023] In order to calculate the perfection of horizontal wells after jetting composite acidizing, the value of the skin coefficient here is mainly affected by acidizing, so it is necessary to calculate the perfection of different areas of a single well section after acidizing, including the local skin coefficient S of jetting acidizing. j and matrix acidification local skin factor S m ;

[0024] S j The calculation formula is shown in formula (4):

[0025] S m The calculation formula is shown in formula (5):

[0026] In formula (4), r w is the borehole radius, and the other values ​​come from step S2. The result S m and S j It can represent the degree of perfection of matrix acidizing zone and jet acidizing zone in different well sections respectively.

[0027] In step S4, the local skin factor of a single section cannot replace the completion degree of the horizontal well as a whole. Therefore, in order to calculate the skin factor of the horizontal well as a whole, the equivalent skin factor of the whole section after hydraulic jetting composite acidizing is obtained by combining the local skin factor of matrix acidizing of a single section and the local skin factor of jetting acidizing: S eq , S eq The calculation formula is shown in formula (6):

[0028]

[0029] In formula (6), N P is the number of injection holes in the horizontal well section. Each horizontal well section generally contains one injection hole, so it can also refer to the number of horizontal well sections; L is the length of the horizontal well section; Δx j is the effective well section length of injection acidizing; h is the reservoir thickness.

[0030] This formula integrates the local skin coefficients of multiple segments into the equivalent skin coefficient of the horizontal well as a whole, which is the most important part of the evaluation of the hydraulic jet composite acidizing effect of open hole horizontal wells. After determining and calculating the skin coefficient data, this method can adjust the injection intensity, injection time and number of injection sections according to the data to make the acidizing efficiency stronger and stronger. It is an important method that can continuously promote the acidizing effect and experience development.

[0031] Finally, the dimensionless yield increase index J in step S5 is s / J0 is the ratio of the production index of the open hole horizontal well after composite acidizing and the initial production index of the open hole horizontal well. This ratio can reflect the final result of the calculation of various engineering parameters. Its value represents the degree of improvement of the oil well production capacity relative to before acidizing. If its value is greater than 1,

[0032] The calculation formula is shown in formula (7):

[0033] In formula (7), β ris the radial flow geometry factor, β l is the linear flow geometry factor, and S0 is the initial wellbore equivalent skin coefficient.

[0034] Where the radial flow geometry factor β r The calculation formula is shown in formula (8):

[0035] The linear flow geometry factor β l The calculation formula is shown in formula (9):

[0036] Under the existing construction capacity, by optimizing the key parameters such as the number of injection sections, the radius of wormhole development in injection acidification, and the radius of wormhole development in matrix acidification, the dimensionless increase ratio of composite acidification under different conditions was obtained. s / J0, corresponding to horizontal wells under different geological reservoir parameter conditions, combined with economic evaluation, the optimal engineering parameters can be determined. During the acidizing process of different horizontal wells, continuous combination and comparison can continuously select various engineering parameters that are suitable for different reservoir geological conditions.

[0037] The advantages of the present invention are as follows: it eliminates the limitation of insufficient transformation and production increase capacity of the entire well section in the single general acidizing process of the prior art, increases the penetration depth and difference of wormholes through the combination of jet acidizing and matrix acidizing, eliminates the surface pollution of the entire well section, adapts to different geological reservoir parameters, and realizes efficient production increase of carbonate open hole horizontal well acidizing; by continuously comparing the surface coefficient and the dimensionless production increase index, the engineering parameters can be continuously optimized, and at the same time, the composite acidizing can be made more economical to the greatest extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The drawings described herein are used to provide a further understanding of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings:

[0039] Figure 1 It is the main flow chart of the present invention;

[0040] Figure 2 It is a cross-sectional schematic diagram of a horizontal well in the present invention;

[0041] Attached Figure 2 Marks and corresponding parts names:

[0042] 1-jet hole; 2-wormhole; 3-toe; 4-root; 5-jet tool; 6-jet acidizing zone; 7-matrix acidizing zone. DETAILED DESCRIPTION

[0043] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0044] In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present invention. However, it is apparent to one of ordinary skill in the art that these specific details are not necessarily employed to practice the present invention. In other embodiments, in order to avoid obscuring the present invention, well-known structures, circuits, materials, or methods are not specifically described.

[0045] Throughout the specification, references to "one embodiment," "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in conjunction with the embodiment or example is included in at least one embodiment of the present invention. Therefore, the phrases "one embodiment," "an embodiment," "an example," or "an example" appearing in various places throughout the specification do not necessarily all refer to the same embodiment or example. In addition, particular features, structures, or characteristics may be combined in one or more embodiments or examples in any suitable combination and / or sub-combination. In addition, it will be appreciated by those of ordinary skill in the art that the figures provided herein are for illustrative purposes and that the figures are not necessarily drawn to scale. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0046] In the description of the present invention, the directions or positional relationships indicated by terms such as “front”, “rear”, “left”, “right”, “up”, “down”, “vertical”, “horizontal”, “high”, “low”, “inside” and “outside” are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limiting the scope of protection of the present invention.

[0047] Example

[0048] A method for evaluating the effect of hydraulic jetting composite acidizing on open hole horizontal well production increase, the main steps are as follows: Figure 1 As shown, the following steps are included:

[0049] S1. Establish a hydraulic jet composite acidizing model based on the actual size of the horizontal well;

[0050] S2. Calculate the effective development radius of the wormhole in the horizontal well according to the above hydraulic jet composite acidizing model;

[0051] S3. Calculate the local skin coefficient in the hydraulic jet composite acidification model according to the above hydraulic jet composite acidification model and the effective development radius of the wormhole;

[0052] S4. Calculate the equivalent skin coefficient of the entire well section after hydraulic jet composite acidizing based on the above local skin coefficient;

[0053] S5. Calculate the dimensionless increase index after acidizing based on the above equivalent skin coefficient and evaluate the effect of composite acidizing;

[0054] The following is the specific content of the embodiment using a set of calculation data as an example:

[0055] S1. Establish a hydraulic jet composite acidizing model based on the actual size of the horizontal well;

[0056] The open hole horizontal well hydraulic jet composite acidizing well model in step S1 is a top view of the horizontal well, which is shown in FIG. Figure 2 As shown, it includes multiple horizontal wells and seepage control range, injection holes and wormholes in each section of the horizontal well.

[0057] In the model of the open hole horizontal well hydraulic jet composite acidizing well embodiment, the open hole horizontal well section length L = 800m, the single well section length Δx = 10m, the wellbore radius r w =0.1m, seepage control radius y b = 200m, reservoir thickness h = 20m, horizontal permeability k H =20mD, vertical permeability k V =10mD, initial wellbore equivalent skin coefficient S0=2.3.

[0058] After these data are determined, drawings of multiple sections of open hole horizontal wells can be drawn. The operation process of hydraulic jet composite acidizing of open hole horizontal wells in carbonate reservoirs has certain requirements for data control. Figure 2 In this embodiment, the part of the horizontal well is divided into three sections, and a jet hole is opened in the center of each section. The jet tool 5 inside the horizontal well moves from the toe 3 to the root 4. After completing the composite acidizing of one section, it is dragged to the next section to continue acidizing. This draggable design allows the interior of the horizontal well to be exposed to the acid as much as possible, which saves material costs and improves the efficiency and coverage of acidizing. There are wormholes 2 around each jet hole caused by acid injection. This part of the jet hole and the wormhole 2 together constitute the jet acidizing area 6, and there are also certain wormholes 2 on the surface of other parts of the horizontal well. These areas constitute the matrix acidizing area 7. It can be seen that it is very important to calculate and evaluate the acidizing effects of the two areas separately and comprehensively obtain the overall acidizing effect for optimizing hydraulic jet composite acidizing.

[0059] Under the high-speed jet of the downhole jet tool 5, the acid will continuously erode and react the well wall rock to form a jet hole 1, and break through the reservoir pollution depth along the jet hole 1 under the pressure squeeze action. After breaking through the inner wall of the jet hole 1, the acid spreads in a dendrite shape to form an acid-etched wormhole 2. Sufficient jetting and impact flow can promote the development of the acid-etched wormhole 2 to the deep reservoir, increasing the coverage of the acidizing effect; and while the acid is being sprayed, the acid that has not entered the jet hole 1 will react with the surrounding open hole section to react with the matrix acidification to remove the surface pollution. The operating efficiency of this jet composite acidification method is greatly affected by the number of jet sections, jet flow and jet time, so the best production increase effect can be obtained through reasonable calculation. This hydraulic jet composite acidification can not only remove the near-well pollution, but also achieve a better acidizing coverage effect and achieve the purpose of increasing production.

[0060] S2. Calculate the effective development radius of the wormhole in the horizontal well according to the above hydraulic jet composite acidizing model;

[0061] In step S2, the entire horizontal well section of the open hole well is first discretized into n single well sections with a length of Δx according to the model in step S1, and then the downhole jetting tool 5 is dragged to perform composite acidizing on each single well section in turn from the "toe 3" to the "root 4" of the horizontal well. After the acidizing of each section is completed, the jetting tool 5 can be dragged to perform the acidizing composite jetting of the next section, which is very convenient to use.

[0062] In this step, the calculation of the effective wormhole 2 radius of the hydraulic jet composite acidification and the effective wormhole 2 radius of the matrix acidification is obtained by calculating the known radial development wormhole 2 radius. If the existing radial development wormhole 2 radius is simply used, the differential development of wormholes caused by formation anisotropy cannot be considered. However, the radius of the wormhole 2 generated in the actual jetting process is larger in the horizontal direction than in the vertical direction, and the overall development range is elliptical. Therefore, it is necessary to add the permeability anisotropy I a Calculations are performed to make the calculated data closer to the true value in order to maximize the acidification coverage and acidification effect.

[0063] Here, the entire horizontal section of the open hole well is discretized into 40 single well sections with a length of Δx = 20m. The downhole jetting tool 5 is dragged from the "toe 3" to the "root 4" of the horizontal well to perform composite acidizing on each single well section. The radial development radius of the wormhole 2 designed for hydraulic jetting composite acidizing in the single well section is r j =1.5m, the effective well section length of the jet acidizing is Δx j =1m; the radial development radius of matrix acidification wormhole 2 in a single well section is r m =0.3m.

[0064] Considering the anisotropy of reservoir permeability in the horizontal and vertical directions, the development of wormhole 2 in the near-wellbore area is elliptical, that is, the length of wormhole 2 in the horizontal direction is greater than the length of wormhole 2 in the vertical direction. The effective wormhole 2 radii of hydraulic jet composite acidizing and matrix acidizing are:

[0065]

[0066]

[0067] in:

[0068]

[0069] In formula (1) and formula (2), r j and r m They are respectively the radial development radius of the wormholes 2 in the hydraulic jet composite acidification zone 6 and the matrix acidification zone 7, that is, the radius of the root of the wormhole 2. Through simple measurement, it can be concluded that due to the impact force, the development radius of the hydraulic jet composite acidification zone 6 is usually higher than that of the matrix acidification zone 7.

[0070] This radius is fixed in direction during measurement. The development direction of wormhole 2 is uncertain. The actual effective development radius is different from the radial development radius. Therefore, it is necessary to use the permeability anisotropy I in formula (3) a The calculation is carried out based on the permeability of the reservoir in both horizontal and vertical directions.

[0071] S3. Calculate the local skin coefficient in the hydraulic jet composite acidification model according to the above hydraulic jet composite acidification model and the effective development radius of the wormhole;

[0072] In step S3, the calculation of the skin coefficient of the single-well section hydraulic jet composite acidizing mainly calculates the skin coefficient, that is, the bottom hole resistance coefficient, which is a dimensionless coefficient indicating the degree of perfection of the well. Its size is determined by multiple factors such as liquid invasion during the completion process, imperfect perforation opening, acidizing, fracturing, and non-Darcy seepage formed by gas near the wellbore.

[0073] In order to measure the perfection of horizontal wells, the value of the skin coefficient here is mainly affected by acidification, so it is necessary to calculate the local skin coefficient S of the injection acidification separately. j and matrix acidification local skin factor S m Among them, the local skin factor of jet acidification and the local skin factor of matrix acidification are:

[0074]

[0075]

[0076] In formulas (4) to (5), S m and S j is the skin coefficient of the jet acidizing zone 6 and the matrix acidizing zone 7. The completion is perfect only when the skin coefficient is less than or equal to 0. The skin coefficients at both ends calculated here are negative values, which means that the state is super perfect and the benefits are higher than those of ordinary acidizing. The jet acidizing skin coefficient here mainly represents the skin coefficient of the jet acidizing zone 6, and the matrix acidizing skin coefficient represents the skin coefficient of the matrix acidizing zone 7. S m >S j , which means that the radius of the wormhole 2 in the jet acidification zone 6 is larger, and its acidification yield-increasing benefit is higher.

[0077] The skin coefficients in the jet acidizing zone 6 and the matrix acidizing zone 7 in this step are calculated by the radial development radius of the wormholes 2 in the two zones and the permeability anisotropy I a The calculation formula is different because the impact force of jet acidification is different from that of matrix acidification and the radius of wormhole 2.

[0078] S4. Calculate the equivalent skin coefficient of the entire well section after hydraulic jet composite acidizing based on the above local skin coefficient;

[0079] Furthermore, in step S4, the local skin coefficient of matrix acidification of a single well section and the local skin coefficient of jet acidification are combined, and the equivalent skin coefficient of the whole well section after hydraulic jet composite acidification is:

[0080]

[0081] In formula (6): S eq is the equivalent skin factor of the entire well section; N P is the number of injection holes 1 in the horizontal well section. Generally, there is one injection hole 1 in each horizontal well section. Here, N P =n=40; ​​L is the length of the horizontal well section, which can be obtained through drilling and completion data; Δx j is the effective well section length of the injection acidizing, that is, the well section length of the injection acidizing zone 6; h is the reservoir thickness, which can be obtained through geological reservoir parameters, and the injection acidizing skin coefficient S j and matrix acidification local skin factor S m Then from step S3.

[0082] The equivalent skin factor S of the entire well section calculated here is eq The value of is reduced from 2.3 to -1.65 relative to the initial equivalent skin coefficient S0 of the entire well section, which not only eliminates the near-well pollution (the skin coefficient is 0 when there is no pollution near the well), but also achieves the effect of increasing production.

[0083] S5. Calculate the dimensionless increase index after acidizing based on the above equivalent skin coefficient and evaluate the effect of composite acidizing;

[0084] In step S5, the production increase effect after composite acidizing can be obtained by calculating the dimensionless production increase index model, thereby further optimizing the construction design parameters. Among them, the dimensionless production increase index Js / J0 is:

[0085]

[0086] in:

[0087]

[0088]

[0089] In formulas (7)-(9), S0 is the initial wellbore equivalent skin coefficient, which is the equivalent skin coefficient before acidizing. βr is the radial flow geometry factor, β l is the linear flow geometry factor, J0 is the initial production index of the open hole horizontal well, J s is the production index of open hole horizontal well after compound acidizing and production enhancement, π is the pi, which is generally taken as 3.14; the seepage control radius y b To control the parameters of acid penetration, 200 is taken here; the reservoir thickness h is 20.

[0090] Dimensionless yield increase index J s If the value of / J0 is equal to 1, it means that the production index of the open hole horizontal well after composite acidizing has not exceeded the initial production index of the open hole horizontal well. In this embodiment, the dimensionless production increase index J s / J0 is 1.16, which is 16% higher than the initial state, and its production increase effect is very obvious.

[0091] Finally, after the calculation in step S5, under the existing construction capacity, the dimensionless increase index under different conditions can be obtained by optimizing the key parameters such as the number of injection sections, the development radius of the hydraulic injection composite acidification wormhole 2, and the development radius of the matrix acidification wormhole 2. The optimal engineering parameters have been determined in combination with economic evaluation. After more attempts have been made by controlling different parameters, the dimensionless increase index J s The value of / J0 will become larger and larger, and the production increase effect will become higher and higher as this evaluation method continues.

[0092] The electronic device may be a computing device such as a desktop computer, a notebook, a PDA, and a cloud server. The electronic device may include, but is not limited to, a processor. Those skilled in the art will appreciate that the schematic diagram is merely an example of an electronic device and does not constitute a limitation on the electronic device. The electronic device may include more or fewer components than shown in the diagram, or may combine certain components, or different components. For example, the electronic device may also include an input / output device, a network access device, etc.

[0093] The processor may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc. The processor is the control center of the electronic device, and uses various interfaces and lines to connect various parts of the entire electronic device.

[0094] The memory can be used to store the computer program or module, and the processor realizes various functions of the electronic device by running or executing the computer program or module stored in the memory, and calling the data stored in the memory. The memory can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, an application required for at least one function (such as a sound playback function, an image playback function, etc.), etc.; the data storage area can store data created according to the use of the mobile phone (such as audio data, a phone book, etc.), etc. In addition, the memory can include a high-speed random access memory, and can also include a non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a smart memory card (Smart Media Caed, SMC), a secure digital (Secure Digital, SD) card, a flash card (FlashCard), at least one disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0095] If the electronic device integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present invention implements all or part of the process in the above-mentioned embodiment method, and can also instruct the relevant hardware to complete it through a computer program. The computer program can be stored in a computer-readable storage medium, and when the computer program is executed by a processor, it can implement the steps of the above-mentioned various method embodiments.

[0096] The computer program includes computer program code, which may be in source code form, object code form, executable file or some intermediate form, etc. The computer readable medium may include: any entity or device capable of carrying the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electric carrier signal, telecommunication signal and software distribution medium, etc. It should be noted that the content contained in the computer readable medium may be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer readable media do not include electric carrier signals and telecommunication signals.

[0097] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for evaluating the production enhancement effect of hydraulic jet composite acidizing in open hole horizontal wells, characterized in that: The following steps are involved: S1. Establish a hydraulic jet composite acidizing model based on the actual size of the horizontal well; S2. According to the above hydraulic jet composite acidizing model, the effective development radius of the wormhole in the horizontal well is calculated. The effective development radius of the wormhole in the hydraulic jet composite acidizing model includes two parts: the effective wormhole radius of the jet acidizing and the effective wormhole radius of the matrix acidizing. The calculation formula of the effective wormhole radius of the jet acidizing is shown in formula (1): je =r j I a Formula (1); The calculation formula of the effective wormhole radius of the matrix acidification is shown in formula (2): me =r m I a Formula (2); In formula (1) and formula (2), r j and r m are the radial development radius of the wormholes in the jet acidification zone and the matrix acidification zone, respectively. a is the permeability anisotropy; S3. According to the above hydraulic jet composite acidification model and the effective development radius of the wormhole, the local skin coefficient in the hydraulic jet composite acidification model is calculated. The calculation of the local skin coefficient in the hydraulic jet composite acidification model includes the injection acidification local skin coefficient S j and matrix acidification local skin factor S m ; S j The calculation formula is shown in formula (4): S m The calculation formula is shown in formula (5): In formulas (4)-(5), r w is the wellbore radius of the horizontal well; S4. Based on the above local skin coefficient, the equivalent skin coefficient after the full-well section hydraulic jetting composite acidizing is calculated. The local skin coefficient of single-well section matrix acidizing and the local skin coefficient of jetting acidizing are combined. The equivalent skin coefficient after the full-well section hydraulic jetting composite acidizing is S eq , S eq The calculation formula is shown in formula (6): In formula (6), N P is the number of injection holes in the horizontal well section, which is consistent with the number of sections of the horizontal well section; Δx j is the effective well section length of the injection acidizing, that is, the well section length of the injection acidizing zone; r w is the wellbore radius of the horizontal well; L is the length of the horizontal well section, and h is the reservoir thickness; S5. According to the above equivalent skin coefficient, the dimensionless increase index after acidification is calculated to evaluate the effect of composite acidification. The dimensionless increase index J s The calculation formula of / J0 is shown in formula (7): In formula (7), βr is the radial flow geometry factor, βl is the linear flow geometry factor, J0 is the initial production index of the open hole horizontal well, and J s S is the production index of open hole horizontal well after composite acidizing stimulation; eq is the equivalent skin coefficient after the completion of hydraulic jet composite acidizing of the whole well section; S0 is the initial equivalent skin coefficient of the whole well section; The open hole horizontal well hydraulic jet composite acidizing well model in step S1 is a top view of the horizontal well, including the horizontal well and the seepage control radius, and the jet holes and wormholes of each section of the horizontal well.

2. The method for evaluating the production enhancement effect of hydraulic jet composite acidizing in open hole horizontal wells according to claim 1, characterized in that: The acidizing method is hydraulic jet composite acidizing using a continuous tubing towed jet tool.

3. The method for evaluating the production enhancement effect of hydraulic jet composite acidizing in open hole horizontal wells according to claim 1, characterized in that: The permeability anisotropy I a The calculation formula is shown in formula (3): In formula (3), k H is the horizontal permeability of the reservoir; k V is the vertical permeability of the reservoir.

4. The method for evaluating the production enhancement effect of hydraulic jet composite acidizing in open hole horizontal wells according to claim 1, characterized in that: Radial flow geometry factor β r The calculation formula is shown in formula (8): Linear flow geometry factor β l The calculation formula is shown in formula (9): In formula (9), π is the circumference of a circle, and the seepage control radius y is b It is the parameter of the wellbore that effectively controls the seepage area.

5. An electronic device, characterized in that include: processor; A memory for storing processor executable instructions; The processor is configured to execute the method for evaluating the effect of hydraulic jet composite acidizing on production enhancement of open hole horizontal wells as described in any one of claims 1 to 4.

6. A computer-readable storage medium, characterized in that The invention comprises a stored computer program, which, when running, executes the method for evaluating the hydraulic jet composite acidizing production enhancement effect of an open hole horizontal well as claimed in any one of claims 1 to 4.

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