Optical fiber flow measuring device, method and system based on peak heating

Abstract

The invention discloses an optical fiber flow measuring device, method and system based on peak heating, and belongs to the technical field of petroleum geophysical exploration and development. According to the optical fiber flow measuring device, the heating devices are arranged at the horizontal bottoms and the upper portions of all the sections, equal-time-interval peak-shaped excitation is conducted on water flow through the heating devices, an inter-section adjacent temperature peak curve is obtained through optical fiber monitoring, and the yield of all the sections can be rapidly quantified. And under the quantitative constraint of the yield of each segment, the cluster yield of each segment is calculated by using a global optimization algorithm. At present, horizontal pressure optical fiber long-term monitoring faces serious temperature excursion, the processing and interpretation precision is low, and an effective flow calibration means is lacked. According to the method, the segmented accurate liquid production capacity of the horizontal well can be obtained, calibration is provided for fine calculation of clustering yield, and the technical problem can be effectively solved.

Description

Technical Field

[0001] The invention belongs to the technical field of petroleum geophysical exploration and development, and relates to an optical fiber flow measurement device, method and system based on peak heating. Background Art

[0002] With the deepening of exploration and development, various oil fields have generally adopted horizontal well staged fracturing technology to increase the production of single wells, but there has been a lack of effective means to dynamically monitor and evaluate the production capacity of horizontal wells. In recent years, distributed fiber optic logging (DTS / DAS) technology has the advantages of small size, light weight, anti-vibration, anti-interference, low power consumption, high sensitivity, ultra-high temperature and pressure resistance, etc., and has received widespread attention from users. Its application surface, application scenarios and application scale are constantly expanding, such as dynamic output monitoring, fracturing monitoring, and water plugging guidance of unconventional shale oil and gas horizontal wells. The rapid development of distributed fiber optic logging dynamic monitoring technology makes horizontal well staged fracturing monitoring and evaluation possible, and is expected to become a technical tool to guide production logging to the middle and high end. However, the existing horizontal well fiber optic logging DTS long-term monitoring data has temperature drift, lacks effective depth calibration and accurate interpretation means, resulting in reduced accuracy of fiber optic interpretation flow; some wells cannot lower the instrument to the bottom of the target layer, resulting in difficulty in calculating the bottom layer production; all of the above will affect the application of fiber optic logging data in oil fields. The existing technology directly uses the global optimization inversion model of the thermal flow field for calculation. This method is prone to multiple solutions, which restricts the large-scale application of existing fiber optic logging technology. There is an urgent need for a flow calibration method to perform cluster production fine calculation under the constraint of segmented flow calibration to improve the accuracy of existing fiber optic DTS logging interpretation. Summary of the invention

[0003] The purpose of the present invention is to solve the problem that the existing technology directly applies the global optimization inversion model of the thermal flow field for calculation. This method is prone to multiple solutions, which restricts the large-scale application of the existing optical fiber logging technology. A fiber optic flow measurement device, method and system based on peak heating are provided.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] The present invention provides an optical fiber flow measurement device based on peak heating, comprising a data processing device, an oil well casing, an oil well tubing and a peak heating device;

[0006] The port of the data processing equipment is connected to an optoelectronic composite cable, which is located between the oil well casing and the oil well tubing; a perforation section is opened on the wall of the oil well casing, and the peak heating device is installed at the other end of the optoelectronic composite cable and is located above the perforation section.

[0007] Preferably, there are several perforation sections;

[0008] Each perforation section consists of several perforation clusters.

[0009] Preferably, the perforation clusters are arranged at equal heights and intervals.

[0010] Preferably, the oil well casing is an L-shaped structure.

[0011] The present invention proposes a method for measuring optical fiber flow based on peak heating, comprising the following steps:

[0012] Obtain the heating time of the peak heating device at the perforation section and the perforation section distance;

[0013] Obtain the fluid velocity in the oil well casing according to the heating time and the distance of the perforation section;

[0014] The wellbore output is obtained based on the fluid flow rate in the oil well casing and the cross-sectional area of ​​the oil well casing to achieve optical fiber flow measurement.

[0015] Preferably, the method for obtaining the fluid flow velocity v in the oil well casing is as follows:

[0016]

[0017] Where l is the average distance between two adjacent peak-shaped thermal marks, and t is the excitation time interval of the spike heating device.

[0018] Preferably, the method for obtaining the wellbore output q is as follows:

[0019] q=(vv 0 ).s

[0020] Where v is the fluid velocity in a certain section of the wellbore, v 0 is the fluid velocity in the previous section of the wellbore, and s is the cross-sectional area of ​​the wellbore.

[0021] The present invention proposes an optical fiber flow measurement system based on peak heating, comprising:

[0022] A data acquisition module, the data acquisition module is used to acquire the heating time of the peak heating device at the perforation section and the perforation section distance;

[0023] A data processing module, the data processing module is used to obtain the fluid flow rate in the oil well casing according to the heating time and the perforation section distance;

[0024] The production acquisition module is used to obtain the wellbore output according to the fluid flow rate in the oil well casing and the cross-sectional area of ​​the oil well casing, so as to realize the optical fiber flow measurement.

[0025] A computer device comprises a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of an optical fiber flow measurement method based on peak heating when executing the computer program.

[0026] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of a method for measuring optical fiber flow based on spike heating.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The present invention proposes a fiber optic flow measurement device based on peak heating, in which a peak heating device is installed on the optoelectronic composite cable and above the perforation section. The peak heating device is used to perform peak-shaped excitation of the water flow in the oil well casing at equal time intervals, and multiple flow calculations can be performed at the same position to ensure that the calculation results are accurate and effective. A peak heating device is provided above the perforation section, and the heating device can be used to calculate the wellbore flow at the corresponding position. The difference in flow can be used to conveniently and precisely obtain the production of the corresponding perforation section. Therefore, the measurement device proposed by the present invention can quickly perform quantitative interpretation of the production of each perforation section, provide calibration for the precise calculation of cluster production, effectively improve the accuracy of fiber optic logging interpretation, and provide a basis for fine adjustment of the profile of injection and production wells in the oil field. After the profile is adjusted, the degree of recovery will increase by 5%.

[0029] The present invention proposes an optical fiber flow measurement method based on peak heating. The adjacent temperature peak curves between segments are obtained through an optoelectronic composite cable. The fluid flow velocity at the corresponding position can be accurately calculated according to the distance difference corresponding to the adjacent peak positions. The flow rate can be used to calculate the flow rate, obtain the precise liquid production of the horizontal well segment, and provide calibration for the fine calculation of cluster production.

[0030] The present invention proposes a peak heating-based optical fiber flow measurement system, which realizes optical fiber flow measurement by dividing the system into a data acquisition module, a data processing module and a yield acquisition module. The modular concept is adopted to make each module independent of each other, which is convenient for unified management of each module. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0032] Figure 1 This is a structural diagram of the optical fiber flow measurement device based on peak heating of the present invention.

[0033] Figure 2 This is a flow chart of the optical fiber flow measurement method based on peak heating of the present invention.

[0034] Figure 3 It is a schematic diagram of the collection and processing method of the present invention.

[0035] Figure 4 This is a peak diagram of adjacent heating intervals (adjacent 5s) at the same peak heating point of the present invention.

[0036] Figure 5 Collect data for the optical fiber logging of the present invention.

[0037] Figure 6 Graphing of optical fiber DTS data of the present invention.

[0038] Figure 7 It is a histogram of segmented yields of the present invention.

[0039] Figure 8 It is a cluster yield bar graph of the present invention.

[0040] Fig. 9 This is a diagram of the optical fiber flow measurement system based on peak heating of the present invention.

[0041] Among them: 1-data processing equipment, 2-photoelectric composite cable, 3-oil well casing, 4-oil well tubing, 5-perforation cluster, 6-perforation section, 7-peak heating device. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0043] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0044] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0045] In the description of the embodiments of the present invention, it should be noted that if the terms "upper", "lower", "horizontal", "inner", etc. indicate an orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use, it is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0046] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", which does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0047] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0048] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0049] The present invention proposes an optical fiber flow measurement device based on peak heating, such as Figure 1 As shown, it includes a data processing device 1, an oil well casing 3, an oil well tubing 4 and a peak heating device 7; the port of the data processing device 1 is connected to a photoelectric composite cable 2, and the photoelectric composite cable 2 is located between the oil well casing 3 and the oil well tubing 4; a perforation section 6 is opened on the wall of the oil well casing 3, and the peak heating device 7 is installed at the other end of the photoelectric composite cable 2 and is located above the perforation section 6.

[0050] Preferably, there are several perforation sections 6, and each perforation section 6 is composed of several perforation clusters 5. The perforation clusters 5 are arranged at equal heights and intervals. The oil well casing 3 is an L-shaped structure.

[0051] The present invention proposes a fiber optic flow measurement device based on peak heating, which obtains the fluid flow velocity between each section by performing peak heating on the water flow + real-time monitoring of the optical cable during collection, and obtains the clustered flow through the global inversion model of the optical fiber temperature field, thereby ultimately improving the accuracy of optical fiber logging interpretation.

[0052] The peak-shaped heating device 7 is a 1m peak-shaped heating device. The optoelectronic composite cable 2 is powered and tested through data processing equipment. It can perform rapid peak-shaped heating on the convection. After heating, the temperature can quickly return to the initial state. The heating time interval of the heating device can be set, generally 2-5s, 5 times in a group; the peak-shaped heating device includes multiple devices, which are fixed on the outside of the optical cable and near the top of each perforation section.

[0053] The present invention proposes a method for measuring optical fiber flow based on peak heating, such as Figure 2 As shown, the following steps are included:

[0054] Step 1, obtaining the heating time of the peak heating device 7 at the perforation section 6 and the distance of the perforation section 6;

[0055] Step 2, obtaining the fluid flow rate in the oil well casing 3 according to the heating time and the distance of the perforation section 6;

[0056] The method for obtaining the fluid velocity v in the oil well casing 3 is as follows:

[0057]

[0058] Where l is the average distance between two adjacent peak-shaped thermal marks, and t is the excitation time interval of the spike heating device.

[0059] Step 3: Obtain the wellbore output according to the fluid flow rate in the oil well casing 3 and the cross-sectional area of ​​the oil well casing 3 to achieve optical fiber flow measurement.

[0060] The method for obtaining the wellbore output q is as follows:

[0061] q=(vv 0 ).s

[0062] Where v is the fluid velocity in a certain section of the wellbore, v 0 is the fluid velocity in the previous section of the wellbore, and s is the cross-sectional area of ​​the wellbore.

[0063] The measurement process of the optical fiber flow measurement device based on spike heating is as follows:

[0064] Set up multiple monitoring work systems from small to large; in the process of each work system from non-steady state to steady state, the data acquisition device 1 is used for monitoring, during which the peak heating device 7 is in the closed state, and the time interval is set to 5 minutes; after each work system optical fiber monitoring reaches the steady state, the data acquisition device 1 continues to monitor for 2-3 hours, and then the data acquisition device 1 monitoring interval is set to 1 second, the peak heating device is turned on, and the optical fiber thermal mark monitoring is carried out; after continuously monitoring 5 groups of peak thermal marks, the peak heating device is turned off, and the wellhead production is modulated to the next work system. The data acquisition device 1 collection time interval is set to 5 minutes, and the next work system monitoring is started until all production work systems are monitored. The data acquisition device 1 is turned on for shut-in monitoring, and the collection time interval is still 5 minutes.

[0065] Next, after waiting for the measurement to be completed, the measured data is processed. First, the peak monitoring data is processed. Five peaks can be monitored on the DTS curve. The average distance between two adjacent peaks is calculated and divided by the excitation time interval of the peak heating device to obtain the total flow velocity v of the fluid under the corresponding section. The total flow velocity minus the total flow velocity of the previous section is the flow velocity corresponding to the fluid in this section. The flow velocity of the fluid in this section multiplied by the cross-sectional area can calculate the output q of this section.

[0066] A perforation section contains several perforation clusters. After the flow rate of each segment is obtained, the flow rate of each segment of the well is assigned using the perforation clusters. Figure 3 The process shown is to perform global optimization inversion flow calculation, and to calculate and obtain the cluster flow of horizontal wells under the constraint of segmented production.

[0067] The present invention is described in detail below with reference to an example, wherein the target well is a horizontal well of shale oil in X oil field, specifically as follows:

[0068] Step 101, the heating device is a 1m peak heating device, which is powered by the wellhead and can perform rapid peak heating on the fluid. The temperature recovers quickly after heating. The heating time interval of the heating device can be set, generally 2-5s, 5 times in a group; the peak heating device includes multiple devices, which are fixed at the bottom of the optical cable and near the top of each perforation section.

[0069] Step 102, measurement process: set up multiple monitoring work systems from small to large; perform optical fiber DTS monitoring during the process of each work system from non-steady state to steady state, during which the peak heating device is in the off state, and the time interval is set to 5 minutes; after each work system optical fiber monitors the steady state, DTS continues to monitor for 2-3 hours, and then the DTS monitoring interval is set to 1 second, the peak heating device is turned on, and optical fiber thermal mark monitoring is performed; after continuously monitoring 5 groups of peak thermal marks, the peak heating device is turned off, the wellhead production is modulated to the next work system, the DTS acquisition time interval is set to 5 minutes, and the next work system monitoring is started until all production work systems are monitored. Then, DTS well shut-in monitoring is started, and the acquisition time interval is still 5 minutes.

[0070] Step 103: After the measurement is completed, the measurement data is processed. First, the peak monitoring data is processed. Five peaks can be monitored on the DTS curve. Figure 4 As shown, the distance between two peaks can be accurately determined; the average distance between two adjacent peaks is calculated, divided by the time interval of the peak heating device excitation, and the total flow velocity v of the fluid under the corresponding section is obtained. The total flow velocity minus the total flow velocity of the previous section is the flow velocity corresponding to the fluid in this section. The flow velocity of the fluid in this section multiplied by the cross-sectional area can calculate the output q of this section. The flow rate of each section is calculated as follows Figure 7 shown.

[0071] Step 104, Figure 5 The monitored DTS data are array temperature data, with depth in the vertical direction and time in the horizontal direction. Figure 6 The DTS waterfall chart shows the array temperature curve monitored by DTS. After the flow rate of each segment is obtained, it is used as a constraint, and the existing temperature field global optimization inversion model algorithm is used to calculate the horizontal well cluster flow rate using DTS data. The calculation results are shown in Figure 8 shown.

[0072] The present invention proposes a fiber optic flow measurement system based on peak heating, such as Fig. 9 As shown, it includes a data acquisition module, a data processing module and a yield acquisition module;

[0073] The data acquisition module is used to acquire the heating time of the peak heating device 7 at the perforation section 6 and the distance of the perforation section 6;

[0074] The data processing module is used to obtain the fluid flow rate in the oil well casing 3 according to the heating time and the distance of the perforation section 6;

[0075] The production acquisition module is used to obtain the wellbore production according to the fluid flow rate in the oil well casing 3 and the cross-sectional area of ​​the oil well casing 3, so as to realize the optical fiber flow measurement.

[0076] The terminal device provided in an embodiment of the present invention comprises: a processor, a memory, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps in the above-mentioned method embodiments are implemented. Alternatively, when the processor executes the computer program, the functions of the modules / units in the above-mentioned device embodiments are implemented.

[0077] The computer program may be divided into one or more modules / units, and the one or more modules / units are stored in the memory and executed by the processor to accomplish the present invention.

[0078] The terminal device may be a computing device such as a desktop computer, a notebook, a PDA, a cloud server, etc. The terminal device may include, but is not limited to, a processor and a memory.

[0079] The processor may be a central processing unit (CPU), or 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.

[0080] The memory may be used to store the computer programs and / or modules, and the processor implements various functions of the terminal device by running or executing the computer programs and / or modules stored in the memory and calling the data stored in the memory.

[0081] If the module / unit integrated in the terminal device 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 processes in the above-mentioned embodiment method, and can also be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of the above-mentioned various method embodiments when executed by the processor. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electric carrier signal, telecommunication signal and software distribution medium. It should be noted that the content contained in the computer-readable medium can 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.

[0082] The optical cable of the present invention adopts a customized optoelectronic composite cable, and peak heating devices are arranged at the bottom of the optical cable and the upper position of each production layer section. The flow rate of each section of the horizontal well is accurately obtained through pulsed peak-shaped thermal marking. Based on the flow constraints of each section, the global optimization algorithm of the temperature field is used to accurately calculate the flow rate of each cluster. This method can effectively solve the technical bottleneck problem of low precision of optical fiber DTS logging, and lay the foundation for further promoting the large-scale application of optical fiber logging in various oil fields.

[0083] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An optical fiber flow measurement device based on peak heating, characterized in that: It comprises a data processing device (1), an oil well casing (3), an oil well tubing (4) and a peak heating device (7); The port of the data processing device (1) is connected to an optoelectronic composite cable (2), and the optoelectronic composite cable (2) is located between the oil well casing (3) and the oil well tubing (4); a perforation section (6) is provided on the wall of the oil well casing (3), and the peak heating device (7) is installed at the other end of the optoelectronic composite cable (2) and is located above the perforation section (6).

2. The optical fiber flow measurement device based on peak heating according to claim 1, characterized in that: There are a plurality of perforation sections (6); Each perforation section (6) is composed of a number of perforation clusters (5).

3. The optical fiber flow measurement device based on peak heating according to claim 2, characterized in that: The perforation clusters (5) are arranged at equal heights and intervals.

4. The optical fiber flow measurement device based on peak heating according to claim 1, characterized in that: The oil well casing (3) is an L-shaped structure.

5. A method for measuring optical fiber flow based on peak heating, characterized in that: The steps include: Obtaining the heating time of the peak heating device (7) at the perforation section (6) and the distance of the perforation section (6); Obtaining the fluid flow rate in the oil well casing (3) according to the heating time and the distance of the perforation section (6); The wellbore output is obtained according to the flow velocity of the fluid in the oil well casing (3) and the cross-sectional area of ​​the oil well casing (3), thereby realizing optical fiber flow measurement.

6. The optical fiber flow measurement method based on peak heating according to claim 5, characterized in that: The method for obtaining the fluid velocity v in the oil well casing (3) is as follows: Where l is the average distance between two adjacent peak-shaped thermal marks, and t is the excitation time interval of the spike heating device.

7. The optical fiber flow measurement method based on peak heating according to claim 5, characterized in that: The method for obtaining the wellbore output q is as follows: q=(v-v0).s Among them, v is the fluid flow velocity in a certain section of the wellbore, v0 is the fluid flow velocity in the previous section of the wellbore, and s is the cross-sectional area of ​​the wellbore.

8. An optical fiber flow measurement system based on peak heating, characterized in that: include: A data acquisition module, the data acquisition module is used to acquire the heating time of the peak heating device (7) at the perforation section (6) and the distance of the perforation section (6); A data processing module, the data processing module being used to obtain the flow rate of the fluid in the oil well casing (3) according to the heating time and the distance of the perforation section (6); A production acquisition module is used to acquire the wellbore production according to the fluid flow rate in the oil well casing (3) and the cross-sectional area of ​​the oil well casing (3), thereby realizing optical fiber flow measurement.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the optical fiber flow measurement method based on spike heating as claimed in any one of claims 5 to 7 are implemented.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the optical fiber flow measurement method based on spike heating as claimed in any one of claims 5 to 7 are implemented.

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