A method, system and product for monitoring reservoir rock structure degradation under high temperature and long-term conditions

Abstract

The invention discloses a method, system and product for monitoring reservoir rock structure degradation under high temperature and long-term conditions, and relates to the field of reservoir rock engineering geomechanics. The method comprises the following steps: arranging an ultrasonic transducer and an EFPI optical fiber sensor on a loading block, and using the ultrasonic transducer to load ultrasonic waves on a rock sample; using the EFPI optical fiber sensor to monitor ultrasonic waves and acoustic emission signals at the rock sample; using standard optimized fast acoustic emission tomography technology to invert a velocity model of the time-varying wave velocity inside the rock sample according to the ultrasonic and acoustic emission signals; using a fast advancement method to perform joint inversion according to the velocity model, the acoustic emission signal and the observation data, and determining the location of rock fractures in the rock sample; the invention can improve the accuracy of monitoring the structural degradation process of the rock under high temperature and long-term conditions and improve the positioning accuracy.

Description

Technical Field

[0001] The present invention relates to the field of reservoir rock mass engineering geomechanics, and in particular to a method, system and product for monitoring reservoir rock mass structural degradation under high temperature and long-term conditions. Background Art

[0002] In the field of reservoir rock engineering geomechanics research, fluid injection into underground rock may induce the initiation and expansion of existing cracks, forming a complex fracture network, causing the rock structure to deteriorate. The deterioration of the rock structure will cause its deformation and strength properties to deteriorate, thereby affecting the stability of the reservoir.

[0003] For the quantitative characterization of rock mass structural degradation, currently available experimental technologies include X-ray computed tomography, nuclear magnetic resonance, geophysical detection, and acoustic emission monitoring. The image resolution or test accuracy of X-ray computed tomography and nuclear magnetic resonance is inversely proportional to the sample size and scanning time, and long-term scanning may cause distortion of the results. Among them, geophysical detection technologies, such as seismic wave velocity detection and electrical resistance tomography, are also effective means to obtain rock mass structure and fracture and fissure structure. However, the disadvantage of such technologies is the multi-solution nature of the inversion results and the large uncertainty. Acoustic emission monitoring technology obtains and processes the stress wave signals generated by internal fractures of the rock mass through acoustic emission probes, which can directly reveal the laws of internal fracture evolution in the rock mass. At present, most acoustic emission probes use piezoelectric ceramic transducers, but the problem of piezoelectric ceramic performance loss under high temperature conditions has not been effectively solved.

[0004] In addition, the premise of studying the extension of rock microcracks is to determine the location of the rock acoustic emission signal. At present, the classic source location method is mostly used for location. Based on the assumption of uniform velocity model, the inversion equation is simplified to a linear form. However, when facing long-term test conditions, the location results are not ideal because they are affected by factors such as the first arrival time of the stress wave, signal-to-noise ratio, velocity model and travel time algorithm, and inversion optimization strategy.

[0005] Therefore, in order to accurately characterize the structural degradation process of rock mass under high temperature and long-term conditions in the field of reservoir rock mass engineering geomechanics research, it is urgent to provide a detection and monitoring system for reservoir rock mass structural degradation. Summary of the invention

[0006] The purpose of the present invention is to provide a method, system and product for monitoring reservoir rock structure degradation under high temperature and long time conditions, which can improve the accuracy of monitoring the structural degradation process of rock mass under high temperature and long time conditions and improve the positioning accuracy.

[0007] To achieve the above-mentioned purpose, the present invention provides the following scheme: a method for monitoring reservoir rock structure degradation under high temperature and long-term conditions, the method comprising: setting an ultrasonic transducer and a non-intrinsic Fabry-Perot interferometer EFPI optical fiber sensor in a loading block, the ultrasonic transducer and the EFPI optical fiber sensor being arranged relative to each other in the loading block; the EFPI optical fiber sensor contacts the rock sample in the loading block through a sensor channel in the loading block; the ultrasonic transducer comprises: a longitudinal wave ultrasonic transducer and a shear wave ultrasonic transducer; a longitudinal wave ultrasonic transducer and a shear wave ultrasonic transducer are arranged in the same direction of the loading block.

[0008] Ultrasonic waves are applied to rock samples using an ultrasonic transducer.

[0009] The ultrasonic and acoustic emission signals at the rock samples were monitored using EFPI fiber optic sensors.

[0010] According to the ultrasonic and acoustic emission signals, the velocity model of the time-varying wave velocity inside the rock sample is inverted using the standard optimized fast acoustic emission tomography technology.

[0011] The location of rock fracture in the rock sample is determined by joint inversion using the rapid marching method based on the velocity model, acoustic emission signals and observation data including EFPI optical fiber sensor coordinates and active / passive arrival times.

[0012] Optionally, ultrasonic waves are loaded onto the rock sample using an ultrasonic transducer, specifically including: performing ultrasonic detection once at specific intervals.

[0013] For step-by-step loading conditions, ultrasonic detection is performed when the pressure value at each level reaches stability.

[0014] Optionally, a rapid advance method is used to perform a joint inversion based on a velocity model, acoustic emission signals and observation data to determine the location of rock fracture in the rock sample, specifically including: a rapid advance method is used to perform a joint inversion based on a velocity model, acoustic emission signals and observation data to determine the theoretical arrival time.

[0015] The arrival time residual is determined based on the signal arrival time obtained from the ultrasonic and acoustic emission signals and the theoretical arrival time; and the minimum arrival time residual is determined within the detection range; the minimum arrival time residual is the location of the rock fracture in the rock sample.

[0016] Determine whether the minimum arrival residual satisfies the error.

[0017] If satisfied, the rock fracture position in the rock sample of active and passive joint inversion is obtained.

[0018] If it is not satisfied, the velocity model is inverted according to the quasi-Newton method combined with the minimum arrival time residual; the inverted velocity model replaces the current velocity model, and the steps of jointly inverting and determining the theoretical arrival time according to the velocity model, acoustic emission signal and observation data using the rapid marching method are repeated until the minimum arrival time residual satisfies the error.

[0019] A reservoir rock structure degradation monitoring system under high temperature and long-term conditions is applied to a reservoir rock structure degradation monitoring method under high temperature and long-term conditions. The system includes: an ultrasonic transducer, an EFPI optical fiber sensor, a data acquisition module, a central processing module, a data communication module and a host computer.

[0020] The ultrasonic transducer is used to load ultrasonic waves on the rock sample.

[0021] The EFPI optical fiber sensor is connected to the ultrasonic transducer and the data acquisition module respectively; the EFPI optical fiber sensor is used to monitor the ultrasonic and acoustic emission signals at the rock sample.

[0022] The central processing module is connected to the EFPI optical fiber sensor, the data acquisition module and the ultrasonic transducer respectively; the central processing module is used to obtain the ultrasonic and acoustic emission signals collected by the data acquisition module, and based on the ultrasonic and acoustic emission signals, use the standard optimized fast acoustic emission tomography technology to invert the velocity model of the wave velocity inside the rock sample changing with time; based on the velocity model, the acoustic emission signal and the observation data, a rapid advancement method is used to perform joint inversion to determine the location of rock fractures in the rock sample; the central processing module is also used to send an excitation instruction to the ultrasonic transducer.

[0023] The host computer communicates with the central processing module and the EFPI optical fiber sensor through the data communication module.

[0024] Optionally, the data acquisition module includes: an ultrasonic emission card and an acoustic emission acquisition card.

[0025] Optionally, the ultrasonic transmitter card is an AD-IPR-1210 ultrasonic transmitter card.

[0026] Optionally, the acoustic emission acquisition card is a PCI-2 acoustic emission acquisition card.

[0027] Optionally, the ultrasonic transducer simulates an active source in the form of a sharp wave pulse, the pulse output voltage is 500V, and the waveform is superimposed 25 times during pulse excitation.

[0028] A computer program product includes a computer program, which, when executed by a processor, implements a method for monitoring reservoir rock structure degradation under high temperature and long-term conditions.

[0029] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects: a method, system and product for monitoring reservoir rock structure degradation under high temperature and long-term conditions provided by the present invention utilizes an ultrasonic transducer based on piezoelectric effect and an EFPI optical fiber sensor based on a micro-electromechanical system (MEMS) to intuitively and in real time obtain information such as the internal wave velocity structure and crack propagation parameters of the rock mass; based on ultrasonic and acoustic emission signals, a standard optimized fast acoustic emission tomography technology is used to invert the velocity model of the internal wave velocity of the rock mass sample changing with time, that is, the present invention adopts the active source (ultrasonic wave) and passive source (acoustic emission) joint detection and monitoring technology principle, utilizes an optical fiber acoustic emission sensor that is adapted to high temperature and long-term working environment, and proposes a technical process for jointly carrying out the detection of P-wave and S-wave velocity fields inside the rock mass during continuous acoustic emission monitoring, and jointly inverts the real-time updated velocity model and the acoustic emission signal to achieve a fine quantitative characterization of the entire process of internal degradation of the rock mass. The change of velocity model can also characterize the formation and expansion process of the fracture network, and verify with stress, strain and acoustic emission event time and space distribution indicators, so as to realize the real-time dynamic tracking of the whole process of rock deformation, damage and fracture. That is, the present invention can improve the accuracy of monitoring the structural degradation process of rock mass under high temperature and long time conditions and improve the positioning accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0031] Figure 1 A schematic flow chart of a method for monitoring reservoir rock structure degradation under high temperature and long-term conditions provided in Example 1 of the present invention.

[0032] Figure 2 This is a schematic diagram of the layout of rock ultrasonic detection and acoustic emission monitoring.

[0033] Figure 3 Schematic diagram of the ultrasonic transducer structure.

[0034] Figure 4 This is the block diagram of the ultrasonic transducer circuit principle.

[0035] Figure 5 Schematic diagram of the EFPI fiber optic sensor model.

[0036] Figure 6 Schematic diagram of the demodulation principle of EFPI fiber optic sensor.

[0037] Figure 7Schematic diagram of ultrasonic transducer detection steps.

[0038] Figure 8 This is the flow chart of joint inversion of wave velocity and acoustic emission.

[0039] Fig. 9 This is a schematic diagram of the structure of a reservoir rock structure degradation monitoring system under high temperature and long-term conditions.

[0040] Fig.10 This is a schematic diagram of the central processing module circuit. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. 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.

[0042] The purpose of the present invention is to provide a method, system and product for monitoring reservoir rock structure degradation under high temperature and long time conditions, which can improve the accuracy of monitoring the structural degradation process of rock mass under high temperature and long time conditions and improve the positioning accuracy.

[0043] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0044] Example 1

[0045] like Figure 1 As shown, the present invention provides a method for monitoring reservoir rock structure degradation under high temperature and long-term conditions, the method comprising: S101, setting an ultrasonic transducer and an EFPI optical fiber sensor on a loading block, such as Figure 2 As shown, the ultrasonic transducer and the EFPI optical fiber sensor are arranged relative to each other in the loading block; the EFPI optical fiber sensor contacts the rock sample in the loading block through the sensor channel in the loading block; the ultrasonic transducer includes: a longitudinal (P) wave ultrasonic transducer and a transverse (S) wave ultrasonic transducer; a P wave ultrasonic transducer and an S wave ultrasonic transducer are arranged in the same direction of the loading block; the EFPI optical fiber sensors are evenly spaced in the loading block, and only one EFPI optical fiber sensor is arranged in each optical fiber channel.

[0046] S102, using an ultrasonic transducer to load ultrasonic waves onto the rock sample.

[0047] like Figure 3 and Figure 4As shown in the figure, the ultrasonic transducer based on the piezoelectric effect converts the input electrical power into mechanical power (i.e. ultrasonic wave) to perform ultrasonic tomography of the rock mass. The ultrasonic transducer is composed of piezoelectric material, electrode, acoustic matching layer, backing, flexible circuit board and shell, etc. It can be used for measurement under high temperature and high pressure conditions. The waveform types that can be excited include square pulse, sharp pulse and modulated pulse. The excitation voltage range is 50V~400V, the pulse width is 20ns~400ns, the resolution is 5ns, the repetition frequency is 2000 / s, and the impedance includes 1Ω, 100Ω and >10kΩ.

[0048] like Figure 7 As shown, it specifically includes: performing ultrasonic detection once every specific time.

[0049] For step-by-step loading conditions, ultrasonic detection is performed when the pressure value at each level reaches stability. Figure 7 The numbers in the middle represent the order and number of ultrasonic detections.

[0050] S103, using EFPI optical fiber sensors to monitor ultrasonic and acoustic emission signals at the rock sample.

[0051] like Figure 5 and Figure 6 As shown, the MEMS-based EFPI fiber sensor is used to receive ultrasonic and acoustic emission signals. The vibration demodulation technology using a sampled grating distributed Bragg reflector tunable laser as the light source, the tunable laser emits a fixed step scanning laser beam according to the signal requirements of the control module, the laser beam is conditioned by the laser output module, and enters the fiber splitter, the control module of the tunable laser sends a control signal and sends a pulse signal to the counting output module, the counting output module receives the pulse signal and outputs the counting signal to the sampling circuit. After receiving the laser beam output by the laser, the fiber splitter divides the laser beam into n channel laser beams, and enters the three-port fiber coupler of the n channels respectively, the fiber coupler outputs the laser beam to the corresponding EFPI fiber sensor. The vibration signal acts on the sensor diaphragm, causing the FP cavity length to change to form an interference spectrum, and returns through the original optical path, and enters the corresponding photodetector through the fiber coupler, the photodetector converts the received reflected laser beam into an electrical signal input amplifier circuit. The amplifier circuit amplifies the received electrical signal and outputs it to the sampling circuit. The sampling circuit uses the counting signal to sample the electrical signal and transmits the obtained sampled data to the communication module to realize information transmission with the monitoring host. The software of the monitoring host realizes waveform spectrum restoration through calculation. The vibration signal of the sensor's environment is reflected through the waveform spectrum, thereby restoring the ultrasonic and acoustic emission signals.

[0052] S104, based on the ultrasonic and acoustic emission signals, the fastmarching acoustic emission tomography using standard optimisation (FaATSO) technique is used to invert the velocity model of the wave velocity inside the rock sample over time.

[0053] S105, performing joint inversion using a rapid advance method based on the velocity model, the acoustic emission signal and the observation data to determine the location of the rock fracture in the rock sample; the observation data includes: EFPI optical fiber sensor coordinates and active / passive arrival times.

[0054] While the rock mass is being loaded, periodic active source (ultrasonic) signal detection and continuous passive source (acoustic emission) signal monitoring are performed. The EFPI fiber optic sensor can collect continuous acoustic emission signals and perform ultrasonic detection at specific intervals after the start of the test. In ultrasonic detection, the ultrasonic transducer simulates the active source in the form of a sharp wave pulse, and the pulse output voltage is set to 500V. When the pulse is excited, the waveform is superimposed 25 times to improve the signal-to-noise ratio. The EFPI fiber optic sensor is used as a receiving sensor to obtain the ultrasonic wave velocity changes during the rock mass loading process.

[0055] like Figure 8 As shown, S106 specifically includes: according to the velocity model, the acoustic emission signal and the observation data, a fast marching method is used to perform a joint inversion to determine the theoretical arrival time.

[0056] The arrival time residual is determined based on the signal arrival time obtained from the ultrasonic and acoustic emission signals and the theoretical arrival time; and the minimum arrival time residual is determined within the detection range; the minimum arrival time residual is the location of the rock fracture in the rock sample.

[0057] Determine whether the minimum arrival residual satisfies the error.

[0058] If satisfied, the rock fracture position in the rock sample of active and passive joint inversion is obtained.

[0059] If it is not satisfied, the velocity model is inverted according to the quasi-Newton method combined with the minimum arrival time residual; the inverted velocity model replaces the current velocity model, and the steps of jointly inverting and determining the theoretical arrival time according to the velocity model, acoustic emission signal and observation data using the rapid marching method are repeated until the minimum arrival time residual satisfies the error.

[0060] Example 2

[0061] like Fig. 9As shown, a reservoir rock structure degradation monitoring system under high temperature and long-term conditions provided by the present invention is applied to a reservoir rock structure degradation monitoring method under high temperature and long-term conditions, and the system includes: an ultrasonic transducer, an EFPI optical fiber sensor, a data acquisition module, a central processing module, a data communication module and a host computer.

[0062] The ultrasonic transducer is used to load ultrasonic waves on the rock sample.

[0063] The EFPI optical fiber sensor is connected to the ultrasonic transducer and the data acquisition module respectively; the EFPI optical fiber sensor is used to monitor the ultrasonic and acoustic emission signals at the rock sample.

[0064] The central processing module is connected to the EFPI optical fiber sensor, the data acquisition module and the ultrasonic transducer respectively; the central processing module is used to obtain the ultrasonic and acoustic emission signals collected by the data acquisition module, and based on the ultrasonic and acoustic emission signals, use the standard optimized fast acoustic emission tomography technology to invert the velocity model of the wave velocity inside the rock sample changing with time; based on the velocity model, the acoustic emission signal and the observation data, a rapid advancement method is used to perform joint inversion to determine the location of rock fractures in the rock sample; the central processing module is also used to send an excitation instruction to the ultrasonic transducer.

[0065] The host computer communicates with the central processing module and the EFPI optical fiber sensor through the data communication module.

[0066] Among them, the data acquisition module and the central processing module constitute the data processing host; the structure of the central processing module is as follows Fig. 9 As shown; the data acquisition module includes: an ultrasonic emission card and an acoustic emission acquisition card.

[0067] The ultrasonic transmitter card is AD-IPR-1210 ultrasonic transmitter card, which has 14-bit D / A accuracy and 100MHz sampling rate.

[0068] The acoustic emission acquisition card is a PCI-2 acoustic emission acquisition card, which has 18-bit analog-to-digital conversion (A / D) accuracy, 10MHz sampling rate and 1kHz~3MHz bandwidth.

[0069] While the rock mass is being loaded, periodic active source (ultrasonic) signal detection and continuous passive source (acoustic emission) signal monitoring are performed. The EFPI fiber optic sensor can collect continuous acoustic emission signals and perform ultrasonic detection at specific intervals after the start of the test. In ultrasonic detection, the ultrasonic transducer simulates the active source in the form of a sharp wave pulse, and the pulse output voltage is set to 500V. When the pulse is excited, the waveform is superimposed 25 times to improve the signal-to-noise ratio. The EFPI fiber optic sensor is used as a receiving sensor to obtain the ultrasonic wave velocity changes during the rock mass loading process.

[0070] Example 3

[0071] A computer program product includes a computer program, which, when executed by a processor, implements a method for monitoring reservoir rock structure degradation under high temperature and long-term conditions in Example 1.

[0072] It should be noted that the object information (including but not limited to object device information, object personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in the present invention are all information and data authorized by the object or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant laws, regulations and standards of relevant countries and regions.

[0073] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided by the present invention can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided by the present invention may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided by the present invention may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but are not limited to this.

[0074] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0075] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A method for monitoring reservoir rock structure degradation under high temperature and long-term conditions, characterized in that: The method comprises: An ultrasonic transducer and a non-intrinsic Fabry-Perot interferometer EFPI optical fiber sensor are arranged in a loading block, and the ultrasonic transducer and the EFPI optical fiber sensor are arranged relative to each other in the loading block; the EFPI optical fiber sensor contacts the rock sample in the loading block through a sensor channel in the loading block; the ultrasonic transducer includes: a longitudinal wave ultrasonic transducer and a shear wave ultrasonic transducer; a longitudinal wave ultrasonic transducer and a shear wave ultrasonic transducer are arranged in the same direction of the loading block; Using ultrasonic transducers to load ultrasonic waves on rock samples; The ultrasonic and acoustic emission signals at the rock samples were monitored using EFPI fiber optic sensors; Based on the ultrasonic and acoustic emission signals, the standard optimized fast acoustic emission tomography technology is used to invert the velocity model of the wave velocity inside the rock sample changing with time; The location of rock fracture in the rock sample is determined by joint inversion using the fast marching method based on the velocity model, acoustic emission signals and observation data; the observation data include: EFPI fiber optic sensor coordinates and active / passive arrival times; Based on the velocity model, acoustic emission signals and observation data, the rapid advance method is used for joint inversion to determine the location of rock fracture in the rock sample, including: The theoretical arrival time is determined by joint inversion using the fast marching method based on the velocity model, acoustic emission signals and observation data. Determine the arrival time residual according to the signal arrival time obtained from the ultrasonic wave and the acoustic emission signal and the theoretical arrival time; and determine the minimum arrival time residual within the detection range; the minimum arrival time residual is the position of the rock fracture in the rock sample; Determine whether the minimum arrival residual satisfies the error; If it is satisfied, the rock fracture position in the rock sample of active and passive joint inversion is obtained; If it is not satisfied, the velocity model is inverted according to the quasi-Newton method combined with the minimum arrival time residual; the inverted velocity model replaces the current velocity model, and the steps of jointly inverting and determining the theoretical arrival time according to the velocity model, acoustic emission signal and observation data using the rapid marching method are repeated until the minimum arrival time residual satisfies the error; Among them, a vibration demodulation technology using a sampled grating distributed Bragg reflection tunable laser as a light source is used. The tunable laser emits a scanning laser beam with a fixed step length according to the signal requirements of the control module. After the laser beam is conditioned by the laser output module, it enters the optical fiber splitter. The control module of the tunable laser sends a pulse signal to the counting output module while sending a control signal. After receiving the pulse signal, the counting output module outputs a counting signal to the sampling circuit. After receiving the laser beam output by the laser, the optical fiber splitter divides the laser beam into n channel laser beams, and enters the three-port optical fiber coupler of the n channels respectively. The optical fiber coupler outputs the laser beam to the corresponding EF On the PI optical fiber sensor; the vibration signal acts on the sensor diaphragm, causing the FP cavity length to change to form an interference spectrum, and returns through the original optical path, and enters the corresponding photodetector through the optical fiber coupler. The photodetector converts the received reflected laser beam into an electrical signal and inputs it into the amplifier circuit; the amplifier circuit amplifies the received electrical signal and outputs it to the sampling circuit. The sampling circuit uses the counting signal to sample the electrical signal and transmits the obtained sampled data to the communication module to realize information transmission with the monitoring host. The software of the monitoring host realizes waveform spectrum restoration through calculation; the vibration signal of the sensor's environment is reflected through the waveform spectrum, thereby restoring the ultrasonic and acoustic emission signals.

2. The method for monitoring reservoir rock structure degradation under high temperature and long-term conditions according to claim 1, characterized in that: The ultrasonic transducer is used to load ultrasonic waves on the rock sample, which specifically includes: Perform ultrasonic detection at specific intervals; For step-by-step loading conditions, ultrasonic detection is performed when the pressure value at each level reaches stability.

3. A system for monitoring reservoir rock structure degradation under high temperature and long-term conditions, applied to a method for monitoring reservoir rock structure degradation under high temperature and long-term conditions as claimed in any one of claims 1 to 2, characterized in that: The system includes: an ultrasonic transducer, an EFPI optical fiber sensor, a data acquisition module, a central processing module, a data communication module and a host computer; The ultrasonic transducer is used to load ultrasonic waves on the rock sample; The EFPI optical fiber sensor is connected to the ultrasonic transducer and the data acquisition module respectively; the EFPI optical fiber sensor is used to monitor the ultrasonic and acoustic emission signals at the rock sample; The central processing module is connected to the EFPI optical fiber sensor, the data acquisition module and the ultrasonic transducer respectively; the central processing module is used to obtain the ultrasonic and acoustic emission signals collected by the data acquisition module, and based on the ultrasonic and acoustic emission signals, adopt the standard optimized fast acoustic emission tomography technology to invert the velocity model of the internal wave velocity of the rock sample changing with time; based on the velocity model, the acoustic emission signal and the observation data, the rapid advancement method is used to perform joint inversion to determine the location of the rock fracture in the rock sample; the central processing module is also used to send an excitation instruction to the ultrasonic transducer; The host computer communicates with the central processing module and the EFPI optical fiber sensor through the data communication module.

4. A reservoir rock structure degradation monitoring system under high temperature and long-term conditions according to claim 3, characterized in that: The data acquisition module includes: an ultrasonic emission card and an acoustic emission acquisition card.

5. A reservoir rock structure degradation monitoring system under high temperature and long-term conditions according to claim 4, characterized in that: The ultrasonic transmitter card is AD-IPR-1210 ultrasonic transmitter card.

6. The system for monitoring reservoir rock structure degradation under high temperature and long-term conditions according to claim 4, characterized in that: The acoustic emission acquisition card is a PCI-2 acoustic emission acquisition card.

7. The system for monitoring reservoir rock structure degradation under high temperature and long-term conditions according to claim 3 is characterized in that: The ultrasonic transducer simulates the active source in the form of sharp wave pulses, the pulse output voltage is 500V, and the waveform is superimposed 25 times during pulse excitation.

8. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, it implements a method for monitoring reservoir rock structure degradation under high temperature and long-term conditions as described in any one of claims 1-2.

Images