A core scale thermal-fluid flow dynamic test platform based on holographic electrical method

Abstract

The application discloses a kind of core scale heat-flow transport dynamic test platform based on holographic electric method, it is related to rock detection technical field, including core bearing module, fluid loading module, holographic electric method acquisition module and control and processing module.The multiple channel layout of holographic electric method acquisition module is realized to the synergic collection of the electrical response of multiple positions of core circumference, to improve the spatial coverage capability of test, the timing control mode of control and processing module is reduced to the mutual interference between different electric method acquisition mode, improve the stability of test data, by joint analysis to electrical data, realize the dynamic characterization of the heat-flow transport process inside core, improve the analysis value of test result, while using functional modular design idea, improve the versatility and scalability of test platform.

Description

Technical Field

[0001] This invention relates to the field of rock testing technology, specifically to a core-scale thermal-fluid transport dynamic testing platform based on holographic electrical methods. Background Technology

[0002] In oil and gas exploration, geothermal resource development, and deep underground engineering research, the fluid transport process inside the core and its accompanying temperature change characteristics are important foundations for revealing the evolution of reservoir properties and the coupling mechanism of multiple physical fields.

[0003] Existing core-scale testing technologies mainly include computed tomography (CT), infrared thermography, and traditional electrical resistivity tomography (OTT). Among them, CT typically requires several minutes to tens of minutes to complete a scan at the core scale, resulting in low temporal resolution and difficulty in capturing transient processes such as fluid transport and thermal front changes. Traditional OTT, due to the limited number of electrodes, can usually only obtain overall or local electrical response information, making it difficult to reflect the spatial distribution characteristics of the internal state of the core.

[0004] Furthermore, existing testing methods mostly focus on acquiring single physical quantities, lacking solutions for the coordinated testing and dynamic analysis of thermal effects and fluid transport processes within the same testing platform. Therefore, it is necessary to provide a core-scale testing platform to achieve continuous and dynamic characterization of heat-fluid transport processes. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the technical solution adopted by this invention is: a core-scale thermal-fluid transport dynamic testing platform based on holographic electrical resistivity tomography (HOT). The testing platform provided by this invention includes a core-bearing module, a fluid loading module, a holographic electrical resistivity tomography acquisition module, and a control and processing module. These functional modules work collaboratively through signal or control connections, thus forming a functionally integrated core-scale HOT dynamic testing platform.

[0006] In this invention, "holographic electrical method" refers to a method of spatially covering and temporally continuous acquisition of the electrical response generated by the heat-fluid transport process inside the core by deploying electrical signal acquisition channels at multiple spatial locations around the core and combining different electrical measurement methods.

[0007] The holographic electrical resistivity acquisition module can employ self-electrostatic measurement to utilize the potential response generated by fluid flow or temperature gradient changes; or it can employ induced polarization measurement to acquire the electrical response related to temperature changes and pore state through an external electrical signal. These methods enable a comprehensive characterization of the changes in the internal thermal and flow fields of the core.

[0008] The holographic electrical resistivity acquisition module is used to acquire electrical signals from multiple spatial locations around the core. This module includes a multi-channel electrode array positioned around the core's circumference. The electrode array can be deployed using a flexible substrate to adapt to the core's shape and achieve a spatial distribution of multiple acquisition channels.

[0009] The control and processing module is used for unified scheduling and data processing of the testing process. This module performs timing control on the fluid loading process and electrical signal acquisition process, and processes and analyzes the acquired electrical data.

[0010] Based on the characteristics that the self-electric signal is sensitive to fluid flow and the induced polarization signal is sensitive to changes in temperature and pore state, the control and processing module performs time-division processing and joint analysis on the collected electrical data, thereby realizing the dynamic characterization of the heat-fluid transport state inside the core.

[0011] The fluid loading module is used to inject fluid into the core and can adjust the flow rate and pressure of the fluid according to preset working conditions to simulate the fluid transport process under different underground environmental conditions. The core bearing module is used to support the core to be tested and can maintain the stability of the environmental conditions of the core during the test through the temperature control unit and the confining pressure control unit.

[0012] During the test, the core-bearing module provides a stable testing environment; the fluid loading module injects fluid into the core according to preset operating conditions; the holographic electrical resistivity acquisition module, under the control of the control and processing module, dynamically acquires the electrical responses at multiple locations around the core; the control and processing module processes and analyzes the acquired electrical data to obtain test results reflecting the dynamic changes in the heat-fluid transport process inside the core. The beneficial effects of this invention are as follows: 1. By deploying a multi-channel holographic electrical resistivity acquisition module, the electrical response at multiple locations around the core is acquired collaboratively, thereby improving the spatial coverage of the test. 2. By using timing control methods in the control and processing modules, mutual interference between different electrical method acquisition methods is reduced, and the stability of test data is improved; 3. By jointly analyzing electrical data, the dynamic characterization of the heat-fluid transport process inside the core is realized, thereby improving the analytical value of the test results. At the same time, the functional modular design concept is adopted to enhance the versatility and scalability of the test platform. Attached Figure Description

[0013] Figure 1 This is a functional module structure diagram of the testing platform of the present invention. Detailed Implementation

[0014] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. The embodiments of the present invention are given for illustrative and descriptive purposes only, and are not intended to be exhaustive or to limit the invention to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described to better illustrate the principles and practical application of the invention, and to enable those skilled in the art to understand the invention and design various embodiments with various modifications suitable for a particular purpose.

[0015] Example 1: This embodiment provides a core-scale thermal-fluid transport dynamic testing platform based on holographic electrical resistivity tomography, including a core bearing module, a fluid loading module, a holographic electrical resistivity tomography acquisition module, and a control and processing module.

[0016] The core support module is used to fix and support the core sample to be tested and to provide stable environmental conditions for core testing. In this embodiment, the core support module may include a confining pressure control unit and a temperature control unit, used to apply a preset confining pressure to the core during the test and maintain the core within a set temperature range, thereby simulating underground environmental conditions.

[0017] The fluid loading module is used to inject fluid into the core to simulate the fluid transport process inside the core. This fluid loading module can adjust the flow rate and pressure of the injected fluid according to preset test conditions, so that the fluid forms a stable or changing flow state inside the core.

[0018] The holographic electrical resistivity acquisition module is used to acquire the electrical response generated by the thermal-fluid transport process inside the core. In this embodiment, the holographic electrical resistivity acquisition module includes a multi-channel electrode array disposed around the core, with each electrode distributed at a predetermined interval on the outer surface of the core to form a spatial coverage electrical signal acquisition of the internal state of the core.

[0019] During the test, the holographic electrical method acquisition module can use the self-electric measurement method to acquire the natural potential signal caused by fluid flow or temperature gradient changes; at the same time or alternatively, it can also use the induced polarization measurement method to obtain electrical information related to the changes in the internal state of the core by applying an excitation signal to the core and acquiring the response signal.

[0020] The control and processing module is used to uniformly control the fluid loading process and the electrical signal acquisition process, and to process and analyze the acquired electrical data. In this embodiment, the control and processing module can control the holographic electrical method acquisition module according to a preset time sequence, so that the self-electric measurement mode and the induced polarization measurement mode are switched in a time-division manner, thereby reducing the mutual interference between different measurement modes.

[0021] The control and processing module can also continuously process and analyze the collected electrical data to generate dynamic test results that reflect the changes in the heat-fluid transport process inside the core over time.

[0022] In the specific testing process, the core is first subjected to preset confining pressure and temperature conditions through the core bearing module; then, fluid is injected into the core through the fluid loading module; during the fluid injection process, the holographic electrical resistivity acquisition module dynamically acquires the electrical response at multiple locations around the core under the control of the control and processing module; the control and processing module processes and analyzes the acquired data to obtain dynamic information reflecting the heat-fluid transport process inside the core.

[0023] Example 2: The thermal-fluid transport dynamic test based on self-electric measurement method has the same overall structure as that in Example 1. The difference is that the holographic electrical method acquisition module mainly uses self-electric measurement method to test the internal state changes of the core.

[0024] During the test, as the fluid migrates within the core and undergoes temperature changes, a spontaneous potential distribution is formed within the core due to fluid flow, electrochemical effects, and the presence of a temperature gradient. The holographic electrical resistivity acquisition module continuously acquires these spontaneous potential signals through a multi-channel electrode array deployed around the core.

[0025] The control and processing module performs time series analysis on the acquired self-electric signals to obtain the response characteristics of the self-electric signals as a function of time. Combined with the operating parameters of the fluid loading module, the module dynamically characterizes the fluid transport process inside the core and the corresponding changes in thermal effects.

[0026] This embodiment enables continuous monitoring of the thermal-fluid transport process inside the core without applying external electrical excitation, and is suitable for testing the core response under natural flow conditions or weak disturbance conditions.

[0027] Example 3: The thermal-fluid transport dynamic test based on induced polarization measurement also includes a core bearing module, a fluid loading module, a holographic electrical resistivity acquisition module, and a control and processing module. The difference is that the holographic electrical resistivity acquisition module mainly uses induced polarization measurement to test the changes in the internal state of the core.

[0028] During the test, the control and processing module controls the holographic electrical resistivity acquisition module to apply a preset electrical excitation signal to the core, and acquires the core's response to the electrical excitation signal through a multi-channel electrode array. The electrical excitation signal can be a pulse signal or an alternating signal to obtain induced polarization response information reflecting changes in the internal electrical properties of the core.

[0029] As fluid migrates within the core and temperature conditions change, the pore structure and electrical parameters of the core alter, leading to corresponding changes in the induced polarization (IP) response signal. The control and processing module continuously processes and analyzes the acquired IPI signals to obtain the characteristics of the IPI response over time, thereby reflecting the dynamic changes in the heat-fluid transport process within the core.

[0030] This embodiment can improve the detection sensitivity of changes in the internal state of the core under external excitation conditions, and is suitable for testing scenarios that are sensitive to changes in temperature or pore structure.

[0031] Example 4: The holographic electrical dynamic test is a time-series coordinated test of self-electricity and induced electricity. The holographic electrical acquisition module supports both self-electricity and induced electricity measurement modes. The control and processing module is configured to control the two measurement modes in a time-division manner.

[0032] Specifically, during the testing process, the control and processing module alternately controls the holographic electrical resistivity acquisition module to perform self-electrical measurement and induced polarization measurement according to a preset time sequence, thereby acquiring two types of electrical response data in the same testing process. Through this method, a multi-dimensional dynamic characterization of the heat-fluid transport process inside the core can be achieved while avoiding interference between different measurement methods.

[0033] The control and processing module can jointly analyze self-electric measurement data and induced polarization measurement data to comprehensively reflect fluid migration behavior and its accompanying thermal effect changes, thereby improving the ability to analyze complex dynamic processes inside the core.

[0034] Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art and related fields based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention. Structures, devices, and operating methods not specifically described and explained in the present invention, unless otherwise specified or limited, shall be implemented according to conventional means in the art.

Claims

1. A core-scale thermal-fluid transport dynamic testing platform based on holographic electrical resistivity tomography, characterized in that, include: The core support module is used to support the core to be tested under preset temperature and confining pressure conditions. A fluid loading module is used to inject fluid into the core to simulate the fluid transport process inside the core. The holographic electrical resistivity acquisition module is used to acquire electrical signals from multiple spatial locations around the core using a multi-channel electrical resistivity acquisition method, in order to obtain electrical data reflecting changes in the internal state of the core. The control and processing module is connected to the fluid loading module and the holographic electrical signal acquisition module, and is used to perform timing control on the fluid loading process and the electrical signal acquisition process, and to process and analyze the acquired electrical data. The control and processing module is configured to control the holographic electrical resistivity acquisition module according to a preset time sequence, so that the electrical data can be used to characterize the dynamic changes of the heat-fluid transport process inside the core.

2. The testing platform according to claim 1, wherein, The holographic electrical resistivity acquisition module includes a multi-channel electrode array arranged around the core, used to form a spatial coverage electrical signal acquisition of the internal state of the core.

3. The testing platform according to claim 2, wherein, The holographic electrical resistivity acquisition module is configured to acquire the electrical response generated by changes in the internal state of the core using at least one of self-electric measurement and induced polarization measurement methods.

4. The testing platform according to claim 3, wherein, The control and processing module is configured to control the self-electric measurement method and the induced polarization measurement method in a time-division multiplexing manner to reduce mutual interference between different electrical acquisition methods.

5. The test platform according to any one of claims 1 to 4, wherein, The control and processing module includes a data analysis unit, which is used to perform joint analysis on the collected electrical data in order to invert the fluid transport process inside the core and the characteristics of its accompanying thermal effects.

6. The test platform according to any one of claims 1 to 5, wherein, The fluid loading module is configured to adjust the flow rate and pressure of the injected fluid according to preset working conditions to simulate the fluid transport process inside the core under different underground environmental conditions.

7. The test platform according to any one of claims 1 to 6, wherein, The core support module includes a temperature control unit and a confining pressure control unit, which are used to maintain the stability of the environmental conditions of the core during the test.

8. The test platform according to any one of claims 1 to 7, wherein, The control and processing module is configured to continuously process the acquired electrical data to generate dynamic test results that reflect the changes in the heat-fluid transport process inside the core over time.

9. The test platform according to any one of claims 1 to 8, wherein, The multi-channel electrode array is deployed using a flexible substrate carrier or other carrier form suitable for the shape of the rock core.

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