Ferromagnetic cavity force magnetic characteristic research experimental device and experimental method

Abstract

The application relates to a ferromagnetic cavity force magnetic characteristic research experimental device and an experimental method. The experimental device and the experimental method measure the change of the space magnetic field of a specified point outside a ferromagnetic cavity under different background magnetic fields and different pressures through a sensor array, are suitable for the research of the force magnetic characteristics of the ferromagnetic cavity under two working conditions that the background magnetic field is changed under the fixed pressure and the pressure is changed under the fixed background magnetic field, and have the advantages of miniaturization, flexible layout, large pressure change range, adjustable background magnetic field, accurate measurement and the like.

Description

Technical Field

[0001] This invention relates to an experimental apparatus and method for studying the mechanical and magnetic properties of ferromagnetic cavities, belonging to the field of physical performance analysis and testing technology. Background Technology

[0002] Deep-sea magnetic detection technology is primarily used to locate and position ferromagnetic targets in the deep sea, such as submarines, shipwrecks, and subsea pipelines. This technology relies on the magnetic anomalies generated by the target within the Earth's magnetic field. The magnetic fields generated by ferromagnetic materials can be categorized into fixed magnetic fields and induced magnetic fields. The magnitude and distribution of the fixed magnetic field are influenced by factors such as the material's magnetism, shape, the geomagnetic field of the construction area, and manufacturing processes. The induced magnetic field is mainly related to the properties and shape of the ferromagnetic material itself, as well as the background magnetic field. The spatial magnetic field anomalies caused by ferromagnetic materials can be detected by magnetic detection instruments, thus enabling the detection and positioning of targets.

[0003] Ferromagnetic cavities, including various functional pipes and underwater vehicles, are typically constructed from ferromagnetic materials. The mechanomagnetic coupling effect of these materials causes their magnetic fields to change with varying forces, thus reducing the accuracy of deep-sea magnetic detection. Therefore, research on the mechanomagnetic properties of ferromagnetic cavities is essential. Research on mechanomagnetic coupling began in 1945, and over decades, a series of theoretical models, such as the Jiles-Atherton theory, have been developed and applied to simulation models. However, current experimental research on mechanomagnetic coupling mainly focuses on rod-shaped structures, which are unsuitable for experimental study due to their enormous size. Summary of the Invention

[0004] This invention discloses an experimental device for studying the magnetic force characteristics of a ferromagnetic cavity under external pressure. The experimental device includes an inner ferromagnetic cavity, an outer pressurized container, a pressurized pump, a compensation current regulation system, a sensor array, and a pressure relief valve.

[0005] The inner ferromagnetic cavity is the experimental object for force-magnetic properties. When the background magnetic field is 0, its remanence will generate a fixed magnetic field in the external space. When it is subjected to pressure, the magnetic field in the external space will change due to the force-magnetic coupling effect.

[0006] The outer pressurized container covers the outside of the inner ferromagnetic cavity and is used to pressurize the inner ferromagnetic cavity;

[0007] The pressurizing pump is used to pressurize the cavity between the inner ferromagnetic cavity and the outer pressurizing container by filling it with water through the water injection valve. It stops working when the pressure reaches the set pressure value.

[0008] The compensation current adjustment system is used to adjust the compensation current in the x, y, and z directions, thereby adjusting the background magnetic field of the inner ferromagnetic cavity.

[0009] The sensor array is used to measure the magnetic field components of corresponding points in the outer space of the inner ferromagnetic cavity. It can measure both absolute and relative quantities. The absolute quantity is the actual magnetic field component of the point in space where the sensor is located, and the relative quantity is the change in the magnetic field component of the point in space where the sensor is located.

[0010] The pressure relief valve is used to relieve pressure in the ferromagnetic cavity. After completing the experiment on the force and magnetic characteristics, the ferromagnetic cavity needs to be depressurized to ensure safety.

[0011] Furthermore, the experimental apparatus for studying the force and magnetic properties of the ferromagnetic cavity under external pressure includes an operating platform; the operating platform is used to control the pressurization speed and pressure value, read the real-time internal pressure through a pressure sensor, and generate time-pressure tables and curves;

[0012] The operating platform is capable of conducting experiments under conditions where the pressure is changed while the background magnetic field is fixed.

[0013] A three-phase fluxgate sensor is placed at the point to be measured to obtain the compensation current data corresponding to the target background magnetic field and the fixed magnetic field distribution of the ferromagnetic cavity.

[0014] After adjusting the compensation current to make the background magnetic field zero, the ferromagnetic cavity is placed at the point to be measured, the data of the sensor array is read, and the fixed magnetic field distribution of the ferromagnetic cavity is measured.

[0015] After adjusting the background magnetic field to the target magnetic field by controlling the compensation current, keep the compensation current constant.

[0016] Fill the cavity with water until it is full and pressurize it. Once the preset pressure is reached, reduce the pressure to 0 and repeat the process twice.

[0017] Data from the sensor array is read to obtain the changes in the magnetic field components under different pressures. Based on the relationship between the changes and the background magnetic field and the pressure inside the cavity, the force-magnetic characteristics are analyzed.

[0018] Furthermore, the operating platform is capable of conducting experiments under conditions where the background magnetic field is changed by a fixed pressure:

[0019] A three-phase fluxgate sensor is placed at the point to be measured to obtain the compensation current data corresponding to the target background magnetic field and the fixed magnetic field distribution of the ferromagnetic cavity.

[0020] After adjusting the compensation current to make the background magnetic field zero, the ferromagnetic cavity is placed at the point to be measured, the data of the sensor array is read, and the fixed magnetic field distribution of the ferromagnetic cavity is measured.

[0021] Fill the cavity with water until it is full, and pressurize it to maintain a constant pressure inside the cavity;

[0022] Controlling the compensation current to adjust the background magnetic field, so that the background magnetic field in the x, y, and z directions follows the range (0, B) max ,0) changes twice;

[0023] By reading the sensor array data, the changes in the magnetic field components corresponding to different background magnetic fields under a fixed pressure are obtained.

[0024] Furthermore, the experimental apparatus for studying the force and magnetic properties of the ferromagnetic cavity under external pressure also includes a water tank and a water injection valve; the water tank is used to store water, and water is injected into the cavity between the inner ferromagnetic cavity and the outer pressurized container through the water injection valve before pressurization.

[0025] Furthermore, the experimental apparatus for studying the force and magnetic properties of the ferromagnetic cavity under external pressure also includes a water storage tank and a drain valve; the water storage tank is used to store the water discharged through the drain valve after the pressure is released, and the drain valve is closed after the drainage is completed, thus ending the experiment.

[0026] Furthermore, the experimental apparatus for studying the force and magnetic properties of the ferromagnetic cavity under external pressure also includes a power supply system; the power supply system supplies power to the pressurization pump, the operating platform, the compensation current adjustment system, and the sensor array.

[0027] Furthermore, the sensor array includes 5 measurement lines with a distance of 200 mm between adjacent measurement lines. Each measurement line has 12 three-phase fluxgate sensors with a distance of 200 mm between adjacent sensors. Each three-phase fluxgate sensor can measure the absolute value and change of the magnetic field component at its spatial point.

[0028] Furthermore, the compensation current adjustment system is used to adjust the compensation current in the x, y, and z directions, thereby adjusting the background magnetic field of the ferromagnetic cavity; three sets of coils, referred to as the x coil, y coil, and z coil respectively, are distributed outside the measurement space and linked to the x, y, and z axes. The current magnitudes in the coils are independent of each other and are superimposed to generate the background magnetic field.

[0029] A method for studying the mechanomagnetic properties of a ferromagnetic cavity is also provided. This method is used to conduct experiments under conditions of changing pressure within a fixed background magnetic field. The method includes the following steps:

[0030] Step 11: Place the ferromagnetic cavity at a remote end to ignore its influence on the background magnetic field of the measurement point, place a three-phase fluxgate sensor at the point to be measured, and read the magnetic field at that point as the background magnetic field of the measurement environment; control the compensation current in the x, y, and z directions to adjust the background magnetic field to the target value, and record the compensation current data corresponding to different target magnetic fields.

[0031] Step 12: Remove the three-phase fluxgate sensor at the point to be measured, adjust the compensation current to make the background magnetic field 0, place the ferromagnetic cavity at the point to be measured, read the data of the sensor array, and measure the fixed magnetic field distribution of the ferromagnetic cavity.

[0032] Step 13: Control the compensation current, adjust the background magnetic field to the target magnetic field, and keep the compensation current unchanged. At this time, the magnetic field in the space to be measured is the target magnetic field.

[0033] Step 14: Close the drain valve, open the water inlet valve, and fill the cavity with water from the water tank until it is full; open the operating platform and adjust the pressurization rate and the upper limit of the pressure stabilization P. max Start the air pump to pressurize the air to P. max Afterwards, turn off the air pump and pressurization valve, and open the pressure relief valve to release the pressure until the pressure inside the cavity is 0. Repeat the above operation twice.

[0034] Step 15: Read the sensor array data to obtain the changes in the magnetic field components under different pressures. Based on the relationship between the changes and the background magnetic field and the pressure inside the cavity, perform a force-magnetic characteristic analysis.

[0035] Step 16: Determine whether the experimental objective has been achieved. If not, return to step 13, change the background magnetic field, and repeat steps 14 and 15. If the objective has been achieved, open the drain valve and close it after draining. The experiment ends.

[0036] A method for studying the mechanomagnetic properties of a ferromagnetic cavity is also provided. This method is used to conduct experiments under conditions of changing pressure within a fixed background magnetic field. The method includes the following steps:

[0037] Step 21: Place the ferromagnetic cavity at a far end to ignore its influence on the background magnetic field of the measurement point, place a three-phase fluxgate sensor at the point to be measured, and read the magnetic field at that point as the background magnetic field of the measurement environment; control the compensation current in the x, y, and z directions to adjust the background magnetic field to the target value, and record the compensation current data corresponding to different target magnetic fields.

[0038] Step 22: Remove the three-phase fluxgate sensor at the point to be measured, adjust the compensation current to make the background magnetic field 0, place the ferromagnetic cavity at the point to be measured, read the data of the sensor array, and measure the fixed magnetic field distribution of the ferromagnetic cavity.

[0039] Step 23: Close the drain valve and open the water inlet valve to fill the cavity with water from the tank. Open the operating platform and adjust the pressurization rate and the upper pressure limit P. max Start the air pump to pressurize the air to P. max Then, keep the pressure inside the cavity constant;

[0040] Step 24: Combining the demagnetizing current corresponding to different background magnetic fields, and according to the experimental requirements, control the compensation current to adjust the background magnetic field so that the background magnetic fields in the x, y, and z directions are aligned with the range (0, B). max ,0) changes twice;

[0041] Step 25: Read the sensor array data to obtain the change in magnetic field components corresponding to different background magnetic fields under a fixed pressure;

[0042] Step 26: Determine if the experimental objective has been achieved. If not, return to step 23, change the pressure, and repeat steps 24 and 25. If the objective has been achieved, close the pressurization valve, open the pressure relief valve to release pressure, open the drain valve after pressure release, and close the drain valve after drainage is complete. The experiment ends.

[0043] The beneficial effects achieved by this invention are:

[0044] The experimental apparatus for studying the mechanomagnetic properties of ferromagnetic cavities provided by this invention has the advantages of miniaturization and flexible layout. This experimental apparatus and method employ an analogical research approach, solving the problem that large ferromagnetic cavities are unsuitable as experimental subjects.

[0045] The experimental apparatus for studying the mechanical and magnetic properties of a ferromagnetic cavity provided by this invention has the advantage of a wide pressure variation range. The ferromagnetic cavity used in the experiment is designed based on the pressure levels experienced on the outer wall of an actual deep-sea ferromagnetic cavity. The pressure experienced by the ferromagnetic cavity can be displayed and recorded in real time, reaching a maximum of MPa.

[0046] The experimental apparatus for studying the mechanomagnetic properties of ferromagnetic cavities provided by this invention is applicable to two working conditions: a fixed pressure with a changed background magnetic field and a fixed background magnetic field with a changed pressure. The change in the external magnetic field of the ferromagnetic cavity is mainly related to the internal pressure and the background magnetic field. This apparatus adopts the concept of the controlled variable method, which supports the exploration of the relationship between a single independent variable and a dependent variable, and is beneficial for the study of the mechanomagnetic properties of ferromagnetic cavities. Attached Figure Description

[0047] Figure 1 This is a schematic diagram of the experimental apparatus for studying the mechanical and magnetic properties of the ferromagnetic cavity of the present invention;

[0048] Figure 2 This is a flowchart of the experimental method for studying the mechanical and magnetic properties of ferromagnetic cavities under a fixed background magnetic field and changing pressure conditions.

[0049] Figure 3 This is a flowchart of the experimental method for studying the mechanical and magnetic properties of a ferromagnetic cavity under the condition of fixed pressure and changing background magnetic field. Detailed Implementation

[0050] The present invention will be further described below with reference to specific embodiments, and the advantages and features of the present invention will become clearer as a result. However, these embodiments are merely exemplary and do not constitute any limitation on the scope of the present invention. Those skilled in the art should understand that modifications or substitutions can be made to the details and form of the technical solutions of the present invention without departing from the spirit and scope of the present invention, but all such modifications and substitutions fall within the protection scope of the present invention.

[0051] Example 1

[0052] As attached Figure 1 As shown, the present invention provides an experimental device for studying the mechanical and magnetic properties of a ferromagnetic cavity. This experimental device is suitable for two working conditions: a fixed background magnetic field with changing pressure and a fixed pressure with changing the background magnetic field. It includes an inner ferromagnetic cavity, an outer pressurized container, a water tank, a pressurized pump, a water storage tank, an operating platform, a compensation current regulation system, a power supply system, a sensor array, a pressure relief valve, a water injection valve, and a drain valve.

[0053] The inner ferromagnetic cavity, used for mechanical and magnetic property experiments, is made of ferromagnetic material. Its magnetization is related to the background magnetic field by a hysteresis loop. When the background magnetic field is zero, its remanence generates a fixed magnetic field in the external space. When subjected to pressure, the external magnetic field changes due to the mechanical-magnetic coupling effect.

[0054] The outer pressure vessel is wrapped around the outer side of the inner ferromagnetic cavity. The outer pressure vessel is used to pressurize the inner ferromagnetic cavity and is made of low magnetic material.

[0055] The water tank is used to store water. Before pressurization, water is injected into the cavity between the inner ferromagnetic cavity and the outer pressurized container through the water injection valve until it is full.

[0056] The pressurization pump is used to fill the cavity between the inner ferromagnetic cavity and the outer pressurization container with water, and then pressurize the cavity between the inner ferromagnetic cavity and the outer pressurization container through the water injection valve. It stops working when the pressure reaches the set pressure value.

[0057] The operating platform is used to control the pressurization rate and pressure value, read the internal real-time pressure through pressure sensors, and generate time-pressure tables and curves.

[0058] The compensation current adjustment system is used to adjust the compensation current in the x, y, and z directions, thereby adjusting the background magnetic field of the inner ferromagnetic cavity. The three types of compensation currents flow independently in three sets of coils linked to the x, y, and z axes, respectively, and superimpose to generate the background magnetic field.

[0059] The sensor array is used to measure the magnetic field components at corresponding points in the outer space of the inner ferromagnetic cavity. It can measure both absolute and relative quantities. The absolute quantity is the actual magnetic field component at the point where the sensor is located, and the relative quantity is the change in the magnetic field component at the point where the sensor is located.

[0060] The power supply system is a collective term for a series of power sources that provide power to modules and systems that require power, such as pressurization pumps, operating platforms, compensation current regulation systems, and sensor arrays.

[0061] The pressure relief valve is used to relieve pressure in the ferromagnetic cavity. After completing the experiment on the force and magnetic characteristics, the ferromagnetic cavity needs to be depressurized to ensure safety.

[0062] The water storage tank is used to store the water discharged through the drain valve after the pressure is released. Once the drainage is complete, the drain valve is closed, and the experiment ends.

[0063] Example 2

[0064] To make the experimental method for studying the mechanical and magnetic properties of ferromagnetic cavities proposed in this invention clearer, the following will be combined with... Figure 2 The experimental methods will be further explained.

[0065] As attached Figure 2 As shown in this embodiment, an experimental method for studying the mechanical and magnetic properties of a ferromagnetic cavity is provided. This experimental method is conducted under the condition of a fixed background magnetic field and varying pressure. The experimental method includes the following steps:

[0066] Step 11: Place the ferromagnetic cavity at a remote location to ignore its influence on the background magnetic field at the measurement point. Place a three-phase fluxgate sensor at the measurement point and read the magnetic field at that point as the background magnetic field of the measurement environment. Control the compensation current in the x, y, and z directions to adjust the background magnetic field to the target value, and record the compensation current data corresponding to different target magnetic fields.

[0067] Step 12: Remove the three-phase fluxgate sensor at the point to be measured, adjust the compensation current to make the background magnetic field 0, place the ferromagnetic cavity at the point to be measured, read the data of the sensor array, and measure the fixed magnetic field distribution of the ferromagnetic cavity.

[0068] Step 13: Control the compensation current, adjust the background magnetic field to the target magnetic field, and keep the compensation current unchanged. At this time, the magnetic field in the space to be measured is the target magnetic field.

[0069] Step 14: Close the drain valve and open the water inlet valve to fill the cavity with water from the tank. Open the operating platform and adjust the pressurization rate and the upper pressure limit P. max Open the pressure valve, close the pressure relief valve, and start the air pump to pressurize. Pressurize to P. max Afterwards, turn off the air pump and pressurization valve, and open the pressure relief valve to release the pressure until the pressure inside the cavity is 0. Repeat the above operation twice.

[0070] Step 15: Read the sensor array data to obtain the changes in the magnetic field components under different pressures. Based on the relationship between the changes and the background magnetic field and the pressure inside the cavity, perform force-magnetic characteristic analysis.

[0071] Step 16: Determine whether the experimental objective has been achieved. If not, return to step 13, change the background magnetic field, and repeat steps 14 and 15. If the objective has been achieved, open the drain valve and close it after draining. The experiment ends.

[0072] Example 3

[0073] As attached Figure 3 As shown in this embodiment, an experimental method for studying the mechanical and magnetic properties of a ferromagnetic cavity is provided. The experiment is conducted under the condition of a fixed pressure and a changed background magnetic field. The experimental method includes the following steps:

[0074] Step 21: Place the ferromagnetic cavity at a remote location to ignore its influence on the background magnetic field at the measurement point. Place a three-phase fluxgate sensor at the measurement point and read the magnetic field at that point as the background magnetic field of the measurement environment. Control the compensation current in the x, y, and z directions to adjust the background magnetic field to the target value, and record the compensation current data corresponding to different target magnetic fields.

[0075] Step 22: Remove the three-phase fluxgate sensor at the point to be measured, adjust the compensation current to make the background magnetic field 0, place the ferromagnetic cavity at the point to be measured, read the data of the sensor array, and measure the fixed magnetic field distribution of the ferromagnetic cavity.

[0076] Step 23: Close the drain valve and open the water inlet valve to fill the cavity with water from the tank. Open the operating platform and adjust the pressurization rate and the upper pressure limit P. max Open the pressure valve, close the pressure relief valve, and start the air pump to pressurize. Pressurize to P. max Then, keep the pressure inside the cavity constant;

[0077] Step 24: Combining the demagnetizing current corresponding to different background magnetic fields, and according to the experimental requirements, control the compensation current to adjust the background magnetic field so that the background magnetic fields in the x, y, and z directions are aligned with the range (0, B). max ,0) changes twice; B max The maximum preset magnetic field strength;

[0078] Step 25: Read the sensor array data to obtain the change in magnetic field components corresponding to different background magnetic fields under a fixed pressure;

[0079] Step 26: Determine if the experimental objective has been achieved. If not, return to step 23, change the pressure, and repeat steps 24 and 25. If the objective has been achieved, close the pressurization valve, open the pressure relief valve to release pressure, open the drain valve after pressure release, and close the drain valve after drainage is complete. The experiment ends.

[0080] This invention is not limited to the specific embodiments described above. Those skilled in the art can implement this invention using various other specific embodiments based on the disclosed content of the embodiments and accompanying drawings. Therefore, any design that adopts the design structure and concept of this invention and makes some simple changes or modifications falls within the protection scope of this invention.

Claims

1. A device for studying the magnetic properties of ferromagnetic cavities under external compressive force, characterized in that, The ferromagnetic cavity outer pressure force magnetic characteristic research experimental device comprises an inner layer ferromagnetic cavity, an outer layer pressurizing container, a pressurizing pump, a compensation current adjusting system, a sensor array, a pressure relief valve and an operation platform. The inner layer ferromagnetic cavity is a force magnetic characteristic experimental object, and when the background magnetic field is 0, the residual magnetism of the inner layer ferromagnetic cavity generates a fixed magnetic field in the outer space; when the inner layer ferromagnetic cavity is subjected to pressure, due to the force magnetic coupling effect, the magnetic field in the outer space changes. The outer layer pressurizing container is wrapped outside the inner layer ferromagnetic cavity and is used for pressurizing the inner layer ferromagnetic cavity. The pressurizing pump is used for pressurizing the cavity between the inner layer ferromagnetic cavity and the outer layer pressurizing container through the water injection valve after the cavity is filled with water, and stops working when the pressure reaches the set value. The compensation current adjusting system is used for adjusting the compensation currents in the x, y and z directions, so as to adjust the background magnetic field in which the inner layer ferromagnetic cavity is located. The sensor array is used for measuring the magnetic field components of the corresponding points in the outer space of the inner layer ferromagnetic cavity, and can measure absolute quantity and relative quantity, wherein the absolute quantity is the actual magnetic field component of the point in the space where the sensor is located, and the relative quantity is the change amount of the magnetic field component of the point in the space where the sensor is located. The pressure relief valve is used for pressure relief of the ferromagnetic cavity, and after the force magnetic characteristic research experiment is completed, the ferromagnetic cavity needs to be depressurized to ensure safety. The operation platform can perform experiments under the condition that the fixed pressure changes the background magnetic field: Three-phase fluxgate sensors are placed at the measuring points, compensation current data corresponding to the target background magnetic field are obtained, and the fixed magnetic field distribution of the ferromagnetic cavity is obtained. After the background magnetic field is adjusted to 0 by adjusting the compensation current, the ferromagnetic cavity is placed at the measuring point, the data of the sensor array are read, and the fixed magnetic field distribution of the ferromagnetic cavity is measured. Water is injected into the cavity until the cavity is filled, and the pressure is kept constant. The compensation current is controlled to adjust the background magnetic field, so that the background magnetic fields in x, y and z directions change twice according to range(0, B max , 0); The sensor array data are read, and the change amount of the magnetic field component corresponding to different background magnetic fields under the fixed pressure is obtained.

2. The experimental apparatus for studying the magnetic properties of ferromagnetic cavities under external compressive force according to claim 1, characterized in that, The operation platform is used for generating a time-pressure table and curve by controlling the pressurizing speed and pressure value and reading the internal real-time pressure through the pressure sensor. The operation platform can perform experiments under the condition that the fixed background magnetic field changes the pressure: Three-phase fluxgate sensors are placed at the measuring points, compensation current data corresponding to the target background magnetic field are obtained, and the fixed magnetic field distribution of the ferromagnetic cavity is obtained. After the background magnetic field is adjusted to 0 by adjusting the compensation current, the ferromagnetic cavity is placed at the measuring point, the data of the sensor array are read, and the fixed magnetic field distribution of the ferromagnetic cavity is measured. The compensation current is controlled, the background magnetic field is adjusted to the target magnetic field, and then the compensation current is kept constant. Water is injected into the cavity until the cavity is filled, and the pressure is kept constant. The sensor array data are read, and the change amount of the magnetic field component corresponding to different background magnetic fields under the fixed pressure is obtained.

3. The experimental apparatus for studying the magnetic properties of ferromagnetic cavities under external compressive force according to claim 1, characterized in that, The ferromagnetic cavity outer pressure force magnetic characteristic research experimental device further comprises a water tank and a water injection valve; the water tank is used for storing water, and the water is injected into the cavity between the inner layer ferromagnetic cavity and the outer layer pressurizing container through the water injection valve before pressurizing.

4. The experimental apparatus for studying the magnetic properties of ferromagnetic cavities under external compressive force according to claim 1, characterized in that, The ferromagnetic cavity external pressure under force magnetic characteristic research experimental device further comprises a water reservoir and a drain valve; the water reservoir is used for storing water discharged through the drain valve after pressure relief is completed, the drain valve is closed after drainage is completed, and the experiment is ended.

5. The experimental apparatus for studying the magnetic properties of ferromagnetic cavities under external compressive force according to claim 2, characterized in that, The ferromagnetic cavity external pressure under force magnetic characteristic research experimental device further comprises a power supply system; the power supply system supplies power for the pressurizing pump, the operation platform, the compensation current adjustment system and the sensor array.

6. The experimental apparatus for studying the magnetic properties of ferromagnetic cavities under external compressive force according to claim 1, characterized in that, The sensor array comprises five measurement lines, the distance between adjacent measurement lines is 200 mm, 12 three-phase fluxgate sensors are distributed on each measurement line, and the distance between adjacent sensors is 200 mm; each three-phase fluxgate sensor can measure the absolute value and the change of the magnetic field component at the space point where the three-phase fluxgate sensor is located.

7. The experimental apparatus for studying the magnetic properties of ferromagnetic cavities under external compressive force according to claim 1, characterized in that, The compensation current regulating system is used for regulating x 、 y 、 z the compensation currents in three directions, so as to regulate the background magnetic field where the ferromagnetic cavity is located. The measuring space is externally distributed with x 、 y 、 z Three groups of coils respectively intersected by three axes are respectively called x coil, y coil and z coil, the current in the coils is independent of each other and superimposed to generate a background magnetic field.

8. A method for studying the ferromagnetic cavity force magnetic properties based on the experimental device for studying the ferromagnetic cavity force magnetic properties according to any one of claims 1-7, characterized in that, The ferromagnetic cavity force magnetic characteristic research experimental method is used for experiments under the condition that the pressure is changed while the background magnetic field is fixed, and the experimental method comprises the following steps: Step 11, place the ferromagnetic cavity at the far end to ignore its effect on the background magnetic field of the measurement point, place a three-phase fluxgate sensor at the point to be measured, read the magnetic field of the point as the background magnetic field of the measurement environment; control x 、 y 、 z the compensation currents of the three directions to adjust the background magnetic field to the target value, and record the compensation current data corresponding to different target magnetic fields; Step 12, the three-phase fluxgate sensor at the to-be-measured point is removed, the compensation current is adjusted to make the background magnetic field 0, the ferromagnetic cavity is placed at the to-be-measured point, the data of the sensor array is read, and the fixed magnetic field distribution of the ferromagnetic cavity is measured; Step 13, the compensation current is controlled, the background magnetic field is adjusted to the target magnetic field, and the compensation current is kept unchanged at this time, and the magnetic field in the to-be-measured space is the target magnetic field; Step 14, close the drain valve, open the water injection valve, inject water into the cavity from the water tank until it is full; open the operation platform, adjust the pressurization rate and the upper limit of pressure stabilization P max ; start the air pump for pressurization, pressurize to P max , then close the air pump and the pressurization valve, open the pressure relief valve for pressure relief, until the pressure in the cavity is 0, the above operations are repeated 2 times; Step 15, the sensor array data is read, the change of the magnetic field component under different pressures is obtained, the force magnetic characteristic analysis is performed according to the relationship between the change, the background magnetic field and the cavity pressure; Step 16, whether the experimental target is completed is judged, if not, step 13 is returned, the background magnetic field is changed, and steps 14 and 15 are repeated, if yes, the drain valve is opened, and the drain valve is closed after drainage is completed, and the experiment is ended.

9. A method for studying the ferromagnetic cavity force magnetic properties based on the experimental device for studying the ferromagnetic cavity force magnetic properties according to any one of claims 1-7, characterized in that, The ferromagnetic cavity force magnetic characteristic research experimental method is used for experiments under the condition that the pressure is changed while the background magnetic field is fixed, and the experimental method comprises the following steps: Step 21, place the ferromagnetic cavity at the far end to ignore its influence on the measured point background magnetic field, place a three-phase fluxgate sensor at the measured point, read the magnetic field of the point as the background magnetic field of the measured environment; control x 、 y 、 z The compensation currents in three directions are adjusted to adjust the background magnetic field to the target value, and the compensation current data corresponding to different target magnetic fields are recorded; Step 22, the three-phase fluxgate sensor at the to-be-measured point is removed, the compensation current is adjusted to make the background magnetic field 0, the ferromagnetic cavity is placed at the to-be-measured point, the data of the sensor array is read, and the fixed magnetic field distribution of the ferromagnetic cavity is measured; Step 23, close the drain valve, open the water injection valve, inject water into the cavity from the water tank until it is full; open the operation platform, adjust the pressurization rate and the upper limit of the pressure stabilization P max ; start the air pump for pressurization, pressurize to P max , and keep the pressure in the cavity unchanged; Step 24, combine the demagnetizing current corresponding to different background magnetic field, according to the experimental requirements, control the compensation current to adjust the background magnetic field, make x , y , z The background magnetic field in three directions changes twice according to range(0, B max , 0); Step 25, the sensor array data is read, the change of the magnetic field component corresponding to different background magnetic fields under the fixed pressure is obtained; Step 26, whether the experimental target is completed is judged, if not, step 23 is returned, the pressure is changed, and steps 24 and 25 are repeated, if yes, the pressurizing valve is closed, the pressure relief valve is opened to perform pressure relief, the drain valve is opened after pressure relief is completed, and the drain valve is closed after drainage is completed, and the experiment is ended.

Images