A device and method for testing dielectric properties of variable temperature rocks

Abstract

The invention discloses a variable-temperature rock dielectric property testing device and a testing method thereof, which relate to the field of microwave technology and include a temperature controller, a vector network analyzer and a dielectric property testing operation platform; the beneficial effects are: by arranging a heating box to slide and adjust its position on a slide rail, the heating position is ensured to be accurate and the heating efficiency is improved; a first guide rail and a second guide rail are arranged to enable the support to slide, and a limit device limits the rightward movement of a top tightening plate to ensure that the inside and outside of a rock sample are in close contact with the inside and outside conductors of a high-temperature coaxial line, thereby avoiding gaps affecting the accuracy of measurement results and reducing measurement errors; a left water-cooling base and a right water-cooling base are arranged for cooling and reducing the temperature, thereby avoiding damage to and influence on a radio frequency coaxial conversion joint; an air pump is arranged to start blowing air as needed, thereby avoiding the influence of irritating odors on rock samples on manual operation.

Description

Technical Field

[0001] The invention relates to the field of microwave technology, and in particular to a device and method for testing dielectric properties of variable-temperature rocks. Background Art

[0002] Microwave-assisted mechanical rock breaking is an auxiliary technology with great application prospects in tunnel construction. Hard rocks are often encountered in the rock breaking process of tunnel boring machines. The rock breaking cutters are subjected to large impact loads, and the key components of the cutter rings and bearings are easily damaged, affecting the construction efficiency. The use of microwave equipment can quickly heat the rock, and the thermal stress causes the micro-cracks inside the rock to crack and expand, reducing the strength and other mechanical properties of the rock. Therefore, the use of microwave-assisted mechanical rock breaking can improve the rock crushing efficiency during tunnel construction, reduce the loss of mechanical equipment, and reduce construction costs.

[0003] The dielectric properties of rock reflect its ability to absorb microwaves. The stronger the dielectric properties, the stronger the ability of rock to absorb microwaves, and the better the microwave heating effect. A set of variable temperature rock dielectric property test equipment is designed to measure the dielectric constant, dielectric loss, dielectric loss tangent and other influencing factors. Before microwave-assisted rock breaking, it is very necessary to accurately understand the dielectric properties of the rock in the construction section. Common rocks at the tunnel construction site were selected for dielectric property tests under variable temperature conditions, and the construction sections suitable for microwave-assisted rock breaking were selected, which has important reference and guiding significance for the engineering application of microwave-assisted mechanical rock breaking. Summary of the invention

[0004] The purpose of the present invention is to provide a variable temperature rock dielectric property testing device and a testing method thereof in order to solve the above problems.

[0005] The present invention achieves the above-mentioned purpose through the following technical solutions:

[0006] A variable temperature rock dielectric property test device, comprising a temperature controller, a vector network analyzer and a dielectric property test operation platform, wherein the dielectric property test operation platform comprises a base, wherein two parallel first guide rails are fixedly installed on the right side of the upper surface of the base, a top tightening plate is slidably arranged on the first guide rail, a force-bearing plate is fixedly installed on the left end of the top tightening plate, a right water-cooled base is fixedly installed on the left side of the force-bearing plate, a second guide rail is fixedly installed on the base corresponding to the position of the right water-cooled base, the right water-cooled base slides on the second guide rail, a left water-cooled base fixedly installed on the base is arranged on the left side of the right water-cooled base, a high-temperature coaxial line is arranged between the left water-cooled base and the right water-cooled base, a heat-insulating coaxial line is fixedly connected to the left and right sides of the high-temperature coaxial line respectively, a water-cooled coaxial line is passed through the left water-cooled base and the right water-cooled base, and the water-cooled coaxial line is fixedly connected to the heat-insulating coaxial line, and the A left RF coaxial conversion joint is fixedly installed on the left side of the left water-cooled base corresponding to the water-cooled coaxial line, and a right RF coaxial conversion joint is fixedly installed on the right side of the right water-cooled base corresponding to the water-cooled coaxial line, and a through hole is opened on the force-bearing plate corresponding to the position of the right RF coaxial conversion joint; a heating box is arranged on the rear side of the high-temperature coaxial line, and a slide rail is fixedly installed on the upper surface of the base corresponding to the position of the heating box, and the heating box slides on the slide rail, and an electromagnetic heating ring is fixedly installed on the front side of the heating box, and the electromagnetic heating ring wraps the high-temperature coaxial line; the high-temperature coaxial line includes a sample holder and high-temperature joints on the left and right sides of the sample holder, and the sample holder and the high-temperature joint are internally provided with inner conductors that are plugged in on the left and right sides; the vector network analyzer is connected to the left RF coaxial conversion joint and the left RF coaxial conversion joint respectively through a waveguide tube; the thermocouple of the temperature controller is inserted into the high-temperature coaxial line.

[0007] Preferably: the rock sample to be tested is placed in a sample holder surrounded by an electromagnetic heating ring.

[0008] Preferably: a limiting device is fixedly installed on the tightening plate, and the limiting device includes a clamping block and a limiting rack. The clamping block moves up and down on the tightening plate, and a supporting spring is fixedly installed between the lower part of the clamping block and the tightening plate. The lower end of the clamping block extends out of the lower surface of the tightening plate and teeth are fixedly installed, and a limiting rack is fixedly installed on the upper surface of the base corresponding to the position of the clamping block.

[0009] Preferably, an air pump is also included, and the air pump extends to above the high-temperature coaxial line through a pipeline.

[0010] Preferably, the temperature of the heating box is adjustable, the temperature range is from room temperature to 600°C, the equipment test frequency is 0.9 to 5 GHz, and the control temperature accuracy is ≤4%.

[0011] Preferably: the upper surfaces of the left water-cooling base and the right water-cooling base are both provided with a cooling water inlet and a cooling water outlet, and are connected to an external water supply pipe.

[0012] The variable temperature rock dielectric property testing method using the variable temperature rock dielectric property testing device includes a rock sample installation method, a test method with a normal temperature test environment, and a test method with a variable temperature test environment.

[0013] The installation method of the rock sample is as follows: the rock sample is placed in the sample holder, the clamping block is pulled upward to compress the support spring, the clamping block and the limit rack are separated, the top clamping plate is pushed to move to the left, the high-temperature joint clamps the sample holder, the inside and outside of the rock sample are in close contact with the inside and outside conductors of the high-temperature coaxial line, the clamping block is released, the teeth at the lower end of the clamping block engage with the limit rack to achieve locking, the heating box is pushed to slide on the slide rail, the position of the electromagnetic heating ring is adjusted to make the sample holder and the rock sample located in the effective heating area of ​​the electromagnetic heating ring, the vector network analyzer is connected to the left RF coaxial conversion joint and the left RF coaxial conversion joint respectively through the waveguide, the thermocouple of the temperature controller is inserted into the high-temperature coaxial line, and the vector network analyzer is connected to an external computer

[0014] When the test environment is measured at room temperature, the specific steps of the test method are as follows:

[0015] Step a1: Initialize the equipment and instruments before testing the variable temperature rock dielectric properties test device to ensure that the equipment is normal;

[0016] Step a2, selecting standard calibration parts to perform through calibration, reflection calibration, and transmission line calibration respectively, to complete the calibration of the vector network analyzer;

[0017] Step a3, the variable temperature rock dielectric property testing device performs dielectric property testing on the polytetrafluoroethylene standard parts at room temperature, and uses the polytetrafluoroethylene standard sample to determine whether the system calibration is successful;

[0018] Step a4: After calibration, insert the hollow columnar rock sample for dielectric property test. When assembling the sample, the end faces need to be aligned and cannot be pushed into the coaxial lines at both ends. Then enter the sample size in the software to perform dielectric property parameter test.

[0019] Step a5, the microwave signal emitted by the vector network analyzer is connected through the right RF coaxial conversion connector, passes through the rock sample to be tested through the coaxial line, and the vector network analyzer collects the feedback microwave signal from the left RF coaxial conversion connector for calculation, obtains the dielectric constant and dielectric loss of the sample material to be tested, and transmits the analysis results to the computer.

[0020] When the test environment is variable temperature measurement, the specific steps are as follows:

[0021] Step b1: Before testing, turn on the water cooler and temperature control box, push the heating box to slide on the slide rail, adjust the position of the electromagnetic heating coil, make the sample holder and the rock sample within the effective heating area of ​​the electromagnetic heating coil, and input the sample size;

[0022] Step b2, after each temperature point is tested, click "Save Data" to obtain the dielectric constant and dielectric loss of the sample material under test, and save the analysis results to the computer, then enter the next temperature point, click "Test after calibration", and test the data of the next temperature point;

[0023] Step b3: After completing the test of all temperature points, pull apart the high-temperature coaxial line, turn on the air pump to the maximum for cooling, and turn off the water cooler after cooling.

[0024] Preferably: in step b1, when the rock sample has a high volatility, the air pump is turned on to blow air toward the rock sample position.

[0025] Compared with the prior art, the beneficial effects of the present invention are: by setting the heating box to slide and adjust the position on the slide rail, the heating position is guaranteed to be accurate and the heating efficiency is improved; the first guide rail and the second guide rail are set to make the support slide, and the limit device limits the rightward movement of the top tightening plate to ensure that the inside and outside of the rock sample are in close contact with the inner and outer conductors of the high-temperature coaxial line, avoiding the gap from affecting the accuracy of the measurement result and reducing the measurement error; a left water-cooled base and a right water-cooled base are set for cooling to avoid damage and influence on the radio frequency coaxial conversion connector; an air pump is set to start blowing as needed to avoid affecting manual operation when there is a pungent smell in the rock sample; by analyzing the influence of temperature on dielectric properties, in the subsequent microwave-assisted rock breaking process, the temperature can be combined with the rock destruction mechanism, and microwave-assisted rock breaking can be performed for different rocks with good microwave absorption performance and high rock damage degree, thereby reducing energy consumption and improving rock breaking efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] 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 or the description of the prior art 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 labor.

[0027] Figure 1 It is a structural schematic diagram of a variable temperature rock dielectric property testing device described in the present invention.

[0028] Figure 2 It is a front view of a dielectric property test operating platform of a variable temperature rock dielectric property test device described in the present invention.

[0029] Figure 3It is a schematic diagram of the three-dimensional structure from the first perspective of a device for testing dielectric properties of variable-temperature rocks according to the present invention.

[0030] Figure 4 It is a schematic diagram of the three-dimensional structure from a second viewing angle of a device for testing dielectric properties of variable-temperature rocks according to the present invention.

[0031] Figure 5 It is a structural schematic diagram of a calibration component group and a rock sample of a variable temperature rock dielectric property testing device described in the present invention.

[0032] The following are the descriptions of the reference numerals:

[0033] 1. Temperature controller; 2. Vector network analyzer; 3. Dielectric properties test operating platform; 4. Heating box; 5. Slide rail; 6. Base; 7. First guide rail; 8. Limit rack; 9. Tightening plate; 10. High-temperature coaxial line; 11. High-temperature connector; 12. Left water-cooled base; 13. Right water-cooled base; 14. Limit device; 15. Sample holder; 16. Electromagnetic heating coil; 17. Right RF coaxial conversion connector; 18. Second guide rail; 19. Force plate; 20. Left RF coaxial conversion connector; 21. Thermal insulation coaxial line; 23. Straight-through calibration piece; 24. Standard calibration piece; 25. Rock sample. DETAILED DESCRIPTION

[0034] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate directions or positional relationships 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, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and the like are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second", and the like may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0035] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" 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 an indirect connection through an intermediate medium, or it can be the internal connection of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0036] The present invention will be further described below in conjunction with the accompanying drawings:

[0037] like Figure 1-Figure 5As shown, a variable temperature rock dielectric property test device includes a temperature controller 1, a vector network analyzer 2 and a dielectric property test operation platform 3, the dielectric property test operation platform 3 includes a base 6, the base 6 is used for supporting, two parallel first guide rails 7 are fixedly installed on the right side of the upper surface of the base 6, a top tightening plate 9 is slidably arranged on the first guide rail 7, a force plate 19 is fixedly installed on the left end of the top tightening plate 9, the force plate 19 is used for transmitting force, a right water-cooled base 13 is fixedly installed on the left side of the force plate 19, a second guide rail 18 is fixedly installed on the position of the base 6 corresponding to the right water-cooled base 13, the first guide rail 7 and the second guide rail 18 are used for guiding movement respectively, the right water-cooled base 13 slides on the second guide rail 18, and a fixedly installed The left water-cooled base 12 on the base 6, the left water-cooled base 12 and the right water-cooled base 13 are used for cooling respectively, a high-temperature coaxial line 10 is arranged between the left water-cooled base 12 and the right water-cooled base 13, and the left and right sides of the high-temperature coaxial line 10 are respectively fixedly connected with the heat-insulating coaxial line 21, the left water-cooled base 12 and the right water-cooled base 13 are penetrated with a water-cooled coaxial line, and the water-cooled coaxial line is fixedly connected with the heat-insulating coaxial line 21, a left RF coaxial conversion joint 20 is fixedly installed on the left side of the left water-cooled base 12 corresponding to the water-cooled coaxial line, the water-cooled coaxial line, the heat-insulating coaxial line 21 and the high-temperature coaxial line 10 are respectively used for waveguide, a right RF coaxial conversion joint 17 is fixedly installed on the right side of the right water-cooled base 13 corresponding to the water-cooled coaxial line, and the force plate 19 corresponds to the right RF coaxial line A through hole is provided at the position of the conversion joint 17; a heating box 4 is provided at the rear side of the high-temperature coaxial line 10, and the heating box 4 is used for heating; a slide rail 5 is fixedly installed on the upper surface of the base 6 corresponding to the position of the heating box 4, and the slide rail 5 is used for directional sliding, and the heating box 4 slides on the slide rail 5; an electromagnetic heating coil 16 is fixedly installed at the front side of the heating box 4, and the electromagnetic heating coil 16 is used for heating, and the electromagnetic heating coil 16 wraps the high-temperature coaxial line 10; the high-temperature coaxial line 10 includes a sample holder 15 and high-temperature joints 11 on the left and right sides of the sample holder 15, and the sample holder 15 and the high-temperature joint 11 are provided with inner conductors that are plugged in on the left and right sides; the vector network analyzer 2 is connected to the left RF coaxial conversion joint 20 and the left RF coaxial conversion joint 20 respectively through a waveguide; the temperature control The thermocouple of the instrument 1 is inserted into the high-temperature coaxial line 10; the rock sample 25 to be tested is placed in the sample holder 15 surrounded by the electromagnetic heating ring 16; the limit device 14 is fixedly installed on the top tightening plate 9, and the limit device 14 includes a clamping block and a limit rack 8. The clamping block moves up and down on the top tightening plate 9, and a support spring is fixedly installed between the lower part of the clamping block and the top tightening plate 9. The support spring is used to support the reset. The lower end of the clamping block extends out of the lower surface of the top tightening plate 9 and is fixedly installed with teeth. The upper surface of the base 6 is fixedly installed with a limit rack 8 corresponding to the position of the clamping block, and the limit rack 8 and the clamping block are locked together; it also includes an air pump, which extends to the top of the high-temperature coaxial line 10 through a pipeline; the temperature of the heating box 4 is adjustable, and the temperature range is: room temperature ~ 600 ° C, and the equipment test frequency is: 0.9~5GHz, control temperature accuracy: ≤4%; the upper surfaces of the left water-cooled base 12 and the right water-cooled base 13 are both provided with cooling water inlet and cooling water outlet, and are connected to the external water supply pipe, and also include a straight-through calibration piece 23, a standard calibration piece 24 and a rock sample 25, and the material of the standard calibration piece 24 is polytetrafluoroethylene. .

[0038] The accuracy of dielectric property parameters of rock sample 25 should meet the following requirements:

[0039] Production requirements of rock sample 25: The sample to be tested is processed into a hollow column, sample size: outer diameter 16mm (negative tolerance), inner diameter 6.95mm (positive tolerance), length 10mm (negative tolerance), both end surfaces of rock sample 25 are smooth and flat, and the inside and outside of the rock sample are in close contact with the inner and outer conductors of the coaxial fixture to avoid air gaps affecting the accuracy of the measurement results and reduce measurement errors.

[0040] Both the through calibration part 23 and the standard calibration part 24 are made of metal materials with high hardness. The materials are first annealed before processing. After processing, the calibration part port and the surface used as the test port are polished and anti-oxidation treated to ensure the stability of the shape and surface electrical properties of the calibration part and the test socket during the calibration process.

[0041] The software of the variable temperature rock dielectric property test device used by the external computer is based on the vector network analyzer 2 and the software provided by the equipment, and uses the driver software of SICL (Standard Instrument Control Library) and VISA (Virtual Instrument Software Architecture) to complete the driving, control and management of the instrument equipment.

[0042] Before the variable temperature rock dielectric properties test system tests the rock sample 25, the test system host must be calibrated first to solve the problems of establishing the calibration parts and calibrating the system errors. The test system adopts TRL (Thru-Reflect-Line) calibration technology to perform through calibration, reflection calibration and transmission line calibration to achieve accurate measurement of precision coaxial systems and non-coaxial systems such as waveguides and microstrip lines. The calibration parts are made of high-hardness alloy and are made of national standard flanges, including three types of test calibration parts: transmission line calibration parts, through calibration parts 23 and standard calibration parts 24.

[0043] When calibrating the transmission line calibration component, the insertion phase of the transmission line should be between 20° and 160° within the frequency range of use. The characteristic impedance of the transmission line and the test port must be consistent, and there should be no discontinuity or step mutation at the connection to ensure reflection-free transmission.

[0044] The variable temperature rock dielectric property testing method using the variable temperature rock dielectric property testing device includes a rock sample installation method, a test method with a normal temperature test environment, and a test method with a variable temperature test environment.

[0045] The installation method of the rock sample 25 is as follows: the rock sample 25 is placed in the sample holder 15, and the support spring is compressed by pulling the card block upward, so that the card block and the limit rack 8 are separated, and the top clamping plate 9 is pushed to move to the left, and the high-temperature joint 11 clamps the sample holder 15, so that the inside and outside of the rock sample 25 are in close contact with the inside and outside conductors of the high-temperature coaxial line 10, and the card block is released, and the teeth at the lower end of the card block are engaged with the limit rack 8 to achieve locking, and the heating box 4 is pushed to slide on the slide rail 5, and the position of the electromagnetic heating coil 16 is adjusted so that the sample holder 15 and the rock sample 25 are located in the effective heating area of ​​the electromagnetic heating coil 16, and the vector network analyzer 2 is respectively connected to the left RF coaxial conversion joint 20 and the left RF coaxial conversion joint 20 through the waveguide, and the thermocouple of the temperature controller 1 is inserted into the high-temperature coaxial line 10, and the vector network analyzer 2 is connected to the external computer

[0046] When the test environment is measured at room temperature, the specific steps of the test method are as follows:

[0047] Step a1: Initialize the equipment and instruments before testing the variable temperature rock dielectric properties test device to ensure that the equipment is normal;

[0048] Step a2, selecting a standard calibration piece 24 to perform through calibration, reflection calibration, and transmission line calibration respectively, to complete the calibration of the vector network analyzer 2;

[0049] Step a3: The variable temperature rock dielectric property test device performs dielectric property test on the polytetrafluoroethylene standard parts at room temperature, and uses the polytetrafluoroethylene standard sample to determine whether the system calibration is successful; (the test result shows that the standard value of the polytetrafluoroethylene dielectric constant is around 2.07, and the error within 10% indicates that the system calibration is successful)

[0050] Step a4: After the calibration is completed, the hollow columnar rock sample 25 is loaded for dielectric property test. When assembling the sample, the end faces need to be aligned and cannot be pushed into the coaxial lines at both ends. Then, the sample size is input into the software to perform dielectric property parameter test.

[0051] Step a5, the microwave signal emitted by the vector network analyzer 2 is connected through the right RF coaxial conversion connector 17, passes through the rock sample 25 to be tested via the coaxial line, and the vector network analyzer 2 collects the feedback microwave signal from the left RF coaxial conversion connector 20 for calculation, obtains the dielectric constant and dielectric loss of the sample material to be tested, and transmits the analysis results to the computer.

[0052] When the test environment is variable temperature measurement, the specific steps are as follows:

[0053] Step b1: Before testing, turn on the water cooler and the temperature control box, push the heating box 4 to slide on the slide rail 5, adjust the position of the electromagnetic heating coil 16, so that the sample holder 15 and the rock sample 25 are located in the effective heating area of ​​the electromagnetic heating coil 16, and input the sample size;

[0054] Step b2, after each temperature point is tested, click "Save Data" to obtain the dielectric constant and dielectric loss of the sample material under test, and save the analysis results to the computer, then enter the next temperature point, click "Test after calibration", and test the data of the next temperature point;

[0055] Step b3: After completing the test of all temperature points, pull apart the high-temperature coaxial line 10, turn on the air pump to the maximum for cooling, and turn off the water cooler after cooling is completed.

[0056] Among them, in step b1, when the rock sample has a high volatility, turn on the air pump to blow air towards the position of the rock sample 25.

[0057] The temperature controller 1, the vector network analyzer 2, the left water-cooling base 12, the right water-cooling base 13, the electromagnetic heating coil 16, the right RF coaxial conversion connector 17 and the left RF coaxial conversion connector 20 are all universal standard parts or parts known to those skilled in the art, and their structures and principles can be known to those skilled in the art through technical manuals or through conventional experimental methods, so they will not be described in detail here.

[0058] The basic principles, main features and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for illustrating the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. A variable temperature rock dielectric property testing device, comprising a temperature controller (1), a vector network analyzer (2) and a dielectric property testing operating platform (3), characterized in that: The dielectric property test operation platform (3) comprises a base (6), two parallel first guide rails (7) are fixedly installed on the right side of the upper surface of the base (6), a top tightening plate (9) is slidably installed on the first guide rail (7), a force-bearing plate (19) is fixedly installed on the left end of the top tightening plate (9), a right water-cooling base (13) is fixedly installed on the left side of the force-bearing plate (19), a second guide rail (18) is fixedly installed on the base (6) at a position corresponding to the right water-cooling base (13), the right water-cooling base (13) slides on the second guide rail (18), a left water-cooling base (12) fixedly installed on the base (6) is arranged on the left side of the right water-cooling base (13), and the left water-cooling base (12) and the right water-cooling base (13) are fixedly installed on the base (6). A high-temperature coaxial line (10) is arranged between the two sides, and the left and right sides of the high-temperature coaxial line (10) are respectively fixedly connected with a heat-insulating coaxial line (21). The left water-cooling base (12) and the right water-cooling base (13) are both penetrated with a water-cooling coaxial line, and the water-cooling coaxial line is fixedly connected to the heat-insulating coaxial line (21). A left radio frequency coaxial conversion joint (20) is fixedly installed on the left side of the left water-cooling base (12) corresponding to the water-cooling coaxial line, and a right radio frequency coaxial conversion joint (17) is fixedly installed on the right side of the right water-cooling base (13) corresponding to the water-cooling coaxial line. A through hole is opened at the position of the force-bearing plate (19) corresponding to the right radio frequency coaxial conversion joint (17); a heating box (4) is arranged on the rear side of the high-temperature coaxial line (10), and the base ( 6) A slide rail (5) is fixedly installed on the upper surface corresponding to the position of the heating box (4), the heating box (4) slides on the slide rail (5), an electromagnetic heating coil (16) is fixedly installed on the front side of the heating box (4), and the electromagnetic heating coil (16) wraps the high-temperature coaxial line (10); the high-temperature coaxial line (10) includes a sample holder (15) and high-temperature connectors (11) on the left and right sides of the sample holder (15), and the sample holder (15) and the high-temperature connector (11) are provided with inner conductors that are plugged in on the left and right sides; the vector network analyzer (2) is connected to the left RF coaxial conversion connector (20) and the left RF coaxial conversion connector (20) respectively through a waveguide; the thermocouple of the temperature controller (1) is plugged into the high-temperature coaxial line (10); The clamping plate (9) is provided with a limit device (14), the limit device (14) comprising a clamping block and a limit rack (8), the clamping block moves up and down on the clamping plate (9), a support spring is fixedly installed between the lower part of the clamping block and the clamping plate (9), the lower end of the clamping block extends out of the lower surface of the clamping plate (9) and a tooth is fixedly installed, and the upper surface of the base (6) is provided with a limit rack (8) corresponding to the position of the clamping block; the rock sample (25) to be tested is placed in a sample holder (15) surrounded by an electromagnetic heating ring (16); the upper surfaces of the left water-cooling base (12) and the right water-cooling base (13) are both provided with a cooling water inlet and a cooling water outlet, and are connected to an external water supply pipe.

2. A variable temperature rock dielectric property testing device according to claim 1, characterized in that: It also includes an air pump, which extends to above the high-temperature coaxial line (10) through a pipeline.

3. A device for testing dielectric properties of variable temperature rocks according to claim 1, characterized in that: The temperature of the heating box (4) is adjustable, the temperature range is: room temperature ~ 600 ° C, the equipment test frequency is: 0.9 ~ 5GHz, and the control temperature accuracy is: ≤4%.

4. A method for testing the dielectric properties of variable-temperature rocks using a device for testing the dielectric properties of variable-temperature rocks according to any one of claims 1 to 3, characterized in that: It includes a rock sample installation method, a test method for measuring in a normal temperature test environment, and a test method for measuring in a variable temperature test environment.

5. A method for testing dielectric properties of variable temperature rocks according to claim 4, characterized in that: The rock sample (25) is installed in the following manner: the rock sample (25) is placed in the sample holder (15), the clamping block is pulled upwards, the support spring is compressed, the clamping block and the limit rack (8) are separated, the top clamping plate (9) is pushed to move to the left, the high temperature joint (11) clamps the sample holder (15), the inside and outside of the rock sample (25) are in close contact with the inside and outside conductors of the high temperature coaxial line (10), the clamping block is released, the teeth at the lower end of the clamping block engage with the limit rack (8) to achieve locking, and the top clamping plate (9) is pushed to move to the left. The heating box (4) slides on the slide rail (5), and the position of the electromagnetic heating coil (16) is adjusted so that the sample holder (15) and the rock sample (25) are located within the effective heating area of ​​the electromagnetic heating coil (16). The vector network analyzer (2) is connected to the left radio frequency coaxial conversion joint (20) and the left radio frequency coaxial conversion joint (20) respectively through a waveguide, the thermocouple of the temperature controller (1) is inserted into the high temperature coaxial line (10), and the vector network analyzer (2) is connected to an external computer.

6. A method for testing dielectric properties of variable temperature rocks according to claim 4, characterized in that: When the test environment is measured at room temperature, the specific steps are as follows: Step a1: Initialize the equipment and instruments before testing the variable temperature rock dielectric properties test device to ensure that the equipment is normal; Step a2, selecting a standard calibration piece (24) to perform through calibration, reflection calibration, and transmission line calibration respectively, to complete calibration of the vector network analyzer (2); Step a3, the variable temperature rock dielectric property testing device performs dielectric property testing on the polytetrafluoroethylene standard parts at room temperature, and uses the polytetrafluoroethylene standard sample to determine whether the system calibration is successful; Step a4: After the calibration is completed, the hollow columnar rock sample (25) is loaded for dielectric property testing. When assembling the sample, the end faces need to be aligned and the sample cannot be pushed into the coaxial lines at both ends. Then, the sample size is input into the software to perform dielectric property parameter testing. Step a5, the microwave signal emitted by the vector network analyzer (2) is connected via the right radio frequency coaxial conversion connector (17), passes through the rock sample (25) to be tested via the coaxial line, and the vector network analyzer (2) collects the feedback microwave signal from the left radio frequency coaxial conversion connector (20) for calculation, obtains the dielectric constant and dielectric loss of the sample material to be tested, and transmits the analysis result to the computer.

7. A method for testing dielectric properties of variable temperature rocks according to claim 4, characterized in that: When the test environment is variable temperature measurement, the specific steps are as follows: Step b1: Before testing, turn on the water cooler and the temperature control box, push the heating box (4) to slide on the slide rail (5), adjust the position of the electromagnetic heating coil (16), make the sample holder (15) and the rock sample (25) located within the effective heating area of ​​the electromagnetic heating coil (16), and input the sample size; Step b2, after each temperature point is tested, click "Save Data" to obtain the dielectric constant and dielectric loss of the sample material under test, and save the analysis results to the computer, then enter the next temperature point, click "Test after calibration", and test the data of the next temperature point; Step b3: After completing the test of all temperature points, pull apart the high-temperature coaxial line (10), turn on the air pump to the maximum for cooling, and turn off the water cooler after cooling is complete.

8. A method for testing dielectric properties of variable temperature rocks according to claim 7, characterized in that: In the step b1, when the rock sample has a high volatility, the air pump is turned on to blow air toward the position of the rock sample (25).

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