Magnetic simulation gravitational field generating device and method for simulating different gravitational fields

Abstract

The invention discloses a magnetic simulation gravitational field generating device and method for simulating different gravitational fields, and belongs to the technical field of geotechnical engineering.The magnetic simulation gravitational field generating device comprises two sets of coils which are coaxially arranged up and down, the centers of the upper and lower sets of coils are hollow, a gap exists in the axial direction, and a test space is located between the two sets of coils; each group of coils comprises a uniform magnetic field coil for generating a uniform magnetic field and a gradient magnetic field coil which is positioned on the outer side of the uniform magnetic field coil and is used for generating a gradient magnetic field with constant magnetic field intensity; the uniform magnetic field coil and the gradient magnetic field coil in the group of coils positioned at the upper part are respectively arranged inside and at the upper end of the top coil bearing platform, and the uniform magnetic field coil group and the gradient magnetic field coil in the group of coils positioned at the lower part are respectively arranged at the upper end and inside the base; the top coil bearing platform and the base are connected through a plurality of side ribs which are symmetrically arranged in the axial direction. The device can be combined with other mechanical equipment conveniently, test phenomena are easy to observe, the test space is large, and a gravity field is convenient to control.

Description

Technical Field

[0001] The present invention belongs to the field of geotechnical engineering technology, and specifically relates to a magnetic pseudo-gravity field generating device and method for simulating different gravity fields. The device is suitable for conducting mechanical tests on geotechnical materials such as simulated lunar soil or simulated pyrotechnical soil under different gravity conditions, such as static penetration tests and load plate tests. Background Art

[0002] Traditional mechanical testing of geotechnical materials is mostly conducted under Earth's standard gravity field. These test results are unlikely to accurately reflect the actual stress and deformation characteristics of extraterrestrial materials, such as lunar and Martian regolith, in low-gravity or even microgravity environments. Therefore, constructing a laboratory test platform capable of accurately simulating different gravity environments has become a key technical challenge urgently needed to be addressed in scientific research and engineering. Existing methods for simulating different gravity environments include: centrifuge test simulation, water seepage force test, tilting model test, drop tower test, parabolic flight test, and magnetic simulated gravity field test. Centrifuge test simulation can only simulate a 1-ng gravity field and cannot simulate a 0-1g gravity field. Water seepage force test utilizes the seepage force generated by water flowing through geotechnical materials to simulate environments under different gravity levels. However, this method is more suitable for saturated soils. For most planets in outer space, there is no water on the surface. For the drop tower test method, parabolic flight test method and inclined model test method, for the first two methods, the low gravity simulation time is short, often less than one minute, making it difficult to conduct experimental research. Although the inclined model test method is not affected by time, the normal gravity component along the inclined surface will also have a certain impact on the test results, thereby causing experimental errors. The test method that uses magnetic force to simulate the gravity field can last for a long time and can form a stable low-gravity environment. It is currently the more ideal method. However, existing magnetic simulated gravity field equipment has certain shortcomings. On the one hand, the uniform magnetic field is mostly in the form of a solenoid, which makes the space relatively closed and difficult to combine with other mechanical equipment and conduct experimental observations. On the other hand, the test space of existing equipment is relatively small, and the solenoid form limits the size of the test space, making it difficult to take into account the size of the space and the uniformity of the magnetic field. Summary of the Invention

[0003] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide a magnetic pseudo-gravity field generating device and method for simulating different gravitational fields, which utilizes Helmholtz coils and Helmholtz coils with reverse current to generate a uniform magnetic field and a magnetic field with a constant magnetic field intensity gradient, respectively.

[0004] The present invention is achieved through the following technical solution: a magnetic pseudo-gravity field generating device for simulating different gravitational fields includes two sets of coils coaxially arranged above and below, the centers of the upper and lower sets of coils are hollow, there is a gap in the axial direction, and the test space is located between the two sets of coils; each set of coils includes a uniform magnetic field coil for generating a uniform magnetic field and a gradient magnetic field coil located outside the uniform magnetic field coil for generating a gradient magnetic field with constant magnetic field intensity.

[0005] Optionally, the uniform magnetic field coil and the gradient magnetic field coil in the upper group of coils are respectively installed in the interior and upper end of the circular top coil support, and the uniform magnetic field coil and the gradient magnetic field coil in the lower group of coils are respectively installed in the upper end and interior of the circular base, and the top coil support and the base are connected by multiple side ribs arranged axially symmetrically.

[0006] Preferably, the side ribs are arranged on the side, 3 on each side and arranged at equal intervals.

[0007] Preferably, the uniform magnetic field coil and the gradient magnetic field coil are unidirectionally wound coil windings.

[0008] Preferably, the uniform magnetic field coil and the gradient magnetic field coil are made of copper wire, and the winding specification is enameled rectangular copper wire.

[0009] Preferably, the base, the top coil support and the side ribs are made of non-ferromagnetic materials.

[0010] Optionally, a control device is also included, which includes a chassis for protecting the internal structure, a control module is arranged inside the chassis, and the control module is electrically connected to the knobs, switches and indicator lights arranged on the front panel of the chassis to achieve unified logical control of each function button.

[0011] Furthermore, a power input port and a current output port are respectively provided on both sides of the chassis. The power input port is used to supply power to the chassis, and the current output port is used to connect a magnetic field generating device to supply power to the coil.

[0012] Furthermore, the knobs, switches and indicator lights include a gradient magnetic field coil power-on indicator light, a uniform magnetic field coil power-on indicator light, a current display screen, a uniform magnetic field coil current control knob, a gradient magnetic field coil current control knob, a uniform magnetic field coil power control switch and a gradient magnetic field coil power control switch; When the uniform magnetic field coil is powered on, the uniform magnetic field coil power-on indicator light lights up; When the gradient magnetic field coil is powered on, the gradient magnetic field coil power-on indicator light lights up; The current display screen is used to display the real-time current and voltage of the uniform magnetic field coil and the gradient magnetic field coil; The uniform magnetic field coil current control knob is used to adjust the current and direction of the uniform magnetic field coil; The gradient magnetic field coil current control knob is used to adjust the current and direction of the gradient magnetic field coil; The uniform magnetic field coil power supply control switch and the gradient magnetic field coil power supply control switch are used to control the power supply of the uniform magnetic field coil and the gradient magnetic field coil respectively.

[0013] A method for simulating different gravitational fields, using the aforementioned magnetic pseudo-gravity field generating device for simulating different gravitational fields, comprises the following steps: (1) Connect the three-phase AC power to the power input port, turn on the uniform magnetic field coil power control switch, and the AC power is converted into DC power inside the chassis and input into the uniform magnetic field coil through the current output port; (2) The indicator light of the uniform magnetic field coil is on. The current input to the uniform magnetic field coil is adjusted to the target value by rotating the current control knob of the uniform magnetic field coil. The real-time current and voltage in the uniform magnetic field coil are displayed on the current display screen. At the same time, the magnetic field intensity and magnetic field intensity gradient at the center of the coil axis test space are displayed. A uniform magnetic field is formed by the uniform magnetic field coil to magnetize the test material, but the gradient magnetic field coil has not yet been powered on. The real-time current and voltage are 0, and the magnetic field intensity gradient should also be 0 kA / m 2 ; (3) Turn on the power control switch of the gradient magnetic field coil. The gradient magnetic field coil power indicator light will light up. Rotate the gradient magnetic field coil current control knob to adjust the current input into the gradient magnetic field coil to the target value. The current display will show the real-time current and voltage in the gradient magnetic field coil. At the same time, it will show the magnetic field intensity and magnetic field intensity gradient at the center of the test space along the coil axis. (4) The saturated magnetized test material located in the test area will produce a magnetic force under the action of the gradient magnetic field. The direction of the magnetic force is the same as the direction of the magnetic flux density gradient. The magnetic force will change the force on the test material and place it in the target gravity field.

[0014] Compared with the prior art, the beneficial effects of the present invention are mainly as follows: (1) Convenient to combine with other mechanical equipment: The magnetic field generating device is mainly composed of two sets of coils, the center of the coils is hollow and transparent from top to bottom. The test space is located between the two sets of coils, which are located above and below the test space respectively, making it convenient to combine with other loading equipment from top to bottom.

[0015] (2) Easy to observe the test phenomena: The sides are open and unobstructed, leaving a lot of empty areas, which is convenient for monitoring the test results and also easy to directly observe the deformation and destructive behavior of the test rock and soil.

[0016] (3) Larger test space: The side is open, making it easy to expand the test space. Compared with the previous solenoid form, the solenoid needs to be lengthened to ensure uniform magnetic field while expanding the space, which is more complicated and difficult to balance the two at the same time. Here, the coil form is adopted, and the coil can be expanded by simply increasing the number of turns.

[0017] (4) Easy to control the gravity field: The current control knob can be used to control the current flow, which can directly control the magnetic field strength and the gradient of the magnetic field strength in the test area, thereby controlling the size of the gravity field in which the test sample is located. In addition, the current input direction can be adjusted through the knob to adjust the simulated hypergravity or low gravity environment.

[0018] (5) Improved test results: This device reduces the difficulty of previous tests in simulated low-gravity environments, such as drop towers and parabolic flights. These tests were difficult to perform and made it difficult to ensure accurate test results. By simulating gravity through a magnetic field, the test environment is relatively more stable and the test results are more reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Other features, purposes and advantages of the present invention will become more apparent by reading the detailed description of the non-limiting embodiments with reference to the following drawings. The following is a brief introduction to the drawings required for describing the embodiments.

[0020] Figure 1 This is a schematic diagram of the coil being energized according to the present invention; Figure 2 This is a front view of the magnetic pseudo-gravity field generating device of the present invention; Figure 3 This is a side view of the magnetic pseudo-gravity field generating device of the present invention; Figure 4 This is a top view of the magnetic pseudo-gravity field generating device of the present invention.

[0021] In the figure: 1- gradient magnetic field coil; 2- uniform magnetic field coil; 3- gradient magnetic field coil power-on indicator light; 4- uniform magnetic field coil power-on indicator light; 5- current display screen; 6- uniform magnetic field coil current control knob; 7- gradient magnetic field coil current control knob; 8- uniform magnetic field coil power control switch; 9- gradient magnetic field coil power control switch; 10- power input port; 11- current output port; 12- chassis; 13- top coil support; 14- side ribs; 15- base. DETAILED DESCRIPTION

[0022] The present invention is described in detail below using specific examples. The following examples will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present invention. Example

[0023] like Figures 1 to 4 As shown, the magnetic pseudo-gravity field generating device for simulating different gravitational fields provided by the present invention includes a magnetic field generating device and a control device, wherein the magnetic field generating device includes two sets of coils arranged coaxially in an upper and lower direction, the centers of the upper and lower sets of coils are hollow, and there is a gap in the axial direction. The test space is located between the two sets of coils, which is convenient for combining with other loading equipment from above and below. Specifically, each set of coils includes a uniform magnetic field coil 2 and a gradient magnetic field coil 1 located outside the uniform magnetic field coil 2. The uniform magnetic field coil 2 is used to generate a uniform magnetic field, and the gradient magnetic field coil 1 is used to generate a magnetic field with a constant magnetic field intensity gradient. The uniform magnetic field coil 2 and the gradient magnetic field coil 1 in the upper set of coils are respectively mounted on the interior and upper end of a circular top coil support 13, while the uniform magnetic field coil group 2 and the gradient magnetic field coil 1 in the lower set of coils are respectively mounted on the upper end and interior of a circular base 15. At the same time, the top coil support 13 and the base 15 are connected by a plurality of axially symmetrical side ribs 14 to support the top coil support 13. More specifically, the top coil support 13 is hollow in the middle, and the hollow part is coaxially arranged with the coil. The side ribs 14 are arranged on the sides, 3 on each side and arranged at equal intervals, so that the front area can be reserved for test observation and monitoring equipment layout. The positioning method is simple to install and is convenient for coil replacement or adjustment, as well as combination with other mechanical equipment.

[0024] In the present invention, since the upper and lower gradient magnetic field coils 1 are relatively far apart, simulating different gravity requires a magnetic field with a constant magnetic field intensity gradient formed by the gradient magnetic field coil 1. The magnetic field intensity gradient required to offset gravity is relatively large. Therefore, the power of the gradient magnetic field coil 1 will be slightly greater than that of the uniform magnetic field coil 2.

[0025] like Figure 2As shown, the control device includes a chassis 12 for protecting the internal structure, and a power input port 10 and a current output port 11 are respectively provided on both sides of the chassis 12. The power input port 10 is used to supply power to the chassis 12, and the current output port 11 is used to connect the magnetic field generating device to supply power to the coil; the chassis 12 is also provided with a gradient magnetic field coil power-on indicator 3, a uniform magnetic field coil power-on indicator 4, a current display screen 5, a uniform magnetic field coil current control knob 6, a gradient magnetic field coil current control knob 7, a uniform magnetic field coil power control switch 8 and a gradient magnetic field coil power control switch 9. Among them, when the uniform magnetic field coil 2 is energized, the uniform magnetic field coil 2 is turned on. The strong magnetic field coil power-on indicator light 4 lights up; after the gradient magnetic field coil 1 is powered on, the gradient magnetic field coil power-on indicator light 3 lights up; the current display screen 5 is used to display the real-time current and voltage of the uniform magnetic field coil 2 and the gradient magnetic field coil 1, which is convenient for controlling the coil current size and thus the magnetic field strength; the uniform magnetic field coil current control knob 6 is used to adjust the current and direction of the uniform magnetic field coil 2; the gradient magnetic field coil current control knob 7 is used to adjust the current and direction of the gradient magnetic field coil 1; the uniform magnetic field coil power control switch 8 and the gradient magnetic field coil power control switch 9 are used to control the power supply of the uniform magnetic field coil 2 and the gradient magnetic field coil 1 respectively.

[0026] In the present invention, a control module is housed within the chassis 12. This module integrates a rectifier and a power supply module, centrally coordinating power supply control and logic regulation. The rectifier converts the input three-phase AC power into DC power, while the power supply module stabilizes the voltage. Control logic is used to control the power supply to the upper and lower coils, including adjusting the current level, direction, and on / off state, enabling unified logical control of each function key. The control module is electrically connected to the knobs, switches, and indicator lights on the front panel of the chassis 12. Specifically, the knob control signal is processed by the control module to adjust the current output to the coils. The real-time current value is detected and fed back to the control module, driving the current display to update in real time. The power-on status signal is detected by the control module and then illuminates the corresponding indicator lights. The power supply module converts the external three-phase AC power into a stable DC current, which is distributed to the uniform magnetic field coil and gradient magnetic field coil via the control module. Protection mechanisms are also implemented, such as automatic power-off for overcurrent and short-circuit protection.

[0027] In some preferred embodiments of the present invention, the uniform magnetic field coil 2 and the gradient magnetic field coil 1 are unidirectionally wound coil windings. The windings for the uniform magnetic field coil 2 and the gradient magnetic field coil 1 are enameled rectangular copper wire. The uniform magnetic field coil 2 and the gradient magnetic field coil 1 are made of copper wire. The base 15, top coil support 13, and side ribs 14 are made of non-ferromagnetic materials.

[0028] When the coil of the present invention is energized, a magnetic field is generated around the coil, such as Figure 1As shown, the uniform magnetic field coil 2 forms a uniform magnetic field between the upper and lower coils, which magnetizes the test material. The gradient magnetic field coil 1 forms a magnetic field with a constant magnetic field gradient in the test space. Since the saturated magnetized material experiences a force in a magnetic field with a constant magnetic field gradient, the gradient of the magnetic field strength can be adjusted by controlling the current, thereby controlling the magnitude of the force applied to the material. This achieves the goal of simulating different gravitational fields. Specifically, when the generated magnetic force partially offsets the gravitational force, a gravitational field of 0-1g can be simulated. Example

[0029] A method for simulating different gravitational fields, using the magnetic pseudo-gravity field generating device for simulating different gravitational fields described in Example 1, comprises the following steps: First, connect the power input port 10 to a three-phase 380V AC power source, then turn on the uniform magnetic field coil power control switch 8. The rectifier inside the chassis 10 will convert the AC power into DC power, and input it into the uniform magnetic field coil 2 through the current output port 11. At this point, the uniform magnetic field coil power indicator 4 lights up, indicating that the control device is powered on normally and the uniform magnetic field coil 2 has been successfully powered on. By rotating the uniform magnetic field coil current control knob 6, the current input from the chassis into the uniform magnetic field coil 2 is adjusted to the target value. At this point, the current display screen 5 will display the real-time current and voltage in the uniform magnetic field coil 2, as well as the magnetic field intensity and magnetic field intensity gradient at the center of the coil axis test space. At this point, a uniform magnetic field will be formed to magnetize the test material, but the gradient magnetic field coil 1 has not yet been powered on. The real-time current and voltage are 0, and the magnetic field intensity gradient should also be 0 kA / m 2 .

[0030] Next, turn on the gradient magnetic field coil power control switch 9. At this time, the gradient magnetic field coil power indicator light 3 lights up, indicating that the gradient magnetic field coil is powered normally. Rotate the gradient magnetic field coil current control knob 7 to adjust the current input into the gradient magnetic field coil 1 to the target value. The current display screen 5 will display the real-time current and voltage in the gradient magnetic field coil, and at the same time display the magnetic field intensity and magnetic field intensity gradient at the center of the coil axis test space.

[0031] Finally, the saturated magnetized test material located in the test area will produce a magnetic force under the action of the gradient magnetic field. The direction of the magnetic force is the same as the direction of the magnetic flux density gradient. The magnetic force will change the force on the test material and place it in the target gravity field.

[0032] The above describes specific embodiments of the present invention. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art may make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. The embodiments of this application and the features in the embodiments may be combined with each other in any manner unless there is a conflict.

Claims

1. A magnetic pseudo-gravity field generating device for simulating different gravitational fields, characterized in that: It includes two sets of coils coaxially arranged above and below. The centers of the upper and lower sets of coils are hollow and there is a gap in the axial direction. The test space is located between the two sets of coils. Each set of coils includes a uniform magnetic field coil for generating a uniform magnetic field and a gradient magnetic field coil located outside the uniform magnetic field coil for generating a gradient magnetic field with constant magnetic field strength.

2. The magnetic pseudo-gravity field generating device for simulating different gravitational fields according to claim 1, characterized in that: The uniform magnetic field coil and the gradient magnetic field coil in the upper group of coils are respectively installed in the interior and upper end of the circular top coil support, and the uniform magnetic field coil and the gradient magnetic field coil in the lower group of coils are respectively installed in the upper end and interior of the circular base, and the top coil support and the base are connected by multiple side ribs arranged axially symmetrically.

3. The magnetic pseudo-gravity field generating device for simulating different gravitational fields according to claim 2, characterized in that: The side ribs are arranged on the side, 3 on each side and equidistantly spaced.

4. The magnetic pseudo-gravity field generating device for simulating different gravitational fields according to claim 2, characterized in that: The uniform magnetic field coil and the gradient magnetic field coil are unidirectionally wound coil windings.

5. The magnetic pseudo-gravity field generating device for simulating different gravitational fields according to claim 2, characterized in that: The uniform magnetic field coil and the gradient magnetic field coil are made of copper wire, and the winding specification is enameled rectangular copper wire.

6. The magnetic pseudo-gravity field generating device for simulating different gravitational fields according to claim 2, characterized in that: The base, the top coil support and the side ribs are made of non-ferromagnetic materials.

7. The magnetic pseudo-gravity field generating device for simulating different gravitational fields according to claim 1, characterized in that: It also includes a control device, which includes a chassis for protecting the internal structure. A control module is arranged inside the chassis. The control module is electrically connected to the knobs, switches and indicator lights arranged on the front panel of the chassis to achieve unified logical control of each function button.

8. The magnetic pseudo-gravity field generating device for simulating different gravitational fields according to claim 7, characterized in that: A power input port and a current output port are respectively provided on both sides of the chassis. The power input port is used to supply power to the chassis, and the current output port is used to connect a magnetic field generating device to supply power to the coil.

9. The magnetic pseudo-gravity field generating device for simulating different gravitational fields according to claim 8, characterized in that: The knobs, switches and indicator lights include a gradient magnetic field coil power-on indicator light, a uniform magnetic field coil power-on indicator light, a current display screen, a uniform magnetic field coil current control knob, a gradient magnetic field coil current control knob, a uniform magnetic field coil power control switch and a gradient magnetic field coil power control switch; When the uniform magnetic field coil is powered on, the uniform magnetic field coil power-on indicator light lights up; When the gradient magnetic field coil is powered on, the gradient magnetic field coil power-on indicator light lights up; The current display screen is used to display the real-time current and voltage of the uniform magnetic field coil and the gradient magnetic field coil; The uniform magnetic field coil current control knob is used to adjust the current and direction of the uniform magnetic field coil; The gradient magnetic field coil current control knob is used to adjust the current and direction of the gradient magnetic field coil; The uniform magnetic field coil power supply control switch and the gradient magnetic field coil power supply control switch are used to control the power supply of the uniform magnetic field coil and the gradient magnetic field coil respectively.

10. A method for simulating different gravitational fields, using the magnetic pseudo-gravity field generating device for simulating different gravitational fields according to any one of claims 1 to 9, characterized in that: The following steps are involved: (1) Connect the three-phase AC power to the power input port, turn on the uniform magnetic field coil power control switch, and the AC power is converted into DC power inside the chassis and input into the uniform magnetic field coil through the current output port; (2) The indicator light of the uniform magnetic field coil is on. The current input to the uniform magnetic field coil is adjusted to the target value by rotating the current control knob of the uniform magnetic field coil. The real-time current and voltage in the uniform magnetic field coil are displayed on the current display screen. At the same time, the magnetic field intensity and magnetic field intensity gradient at the center of the coil axis test space are displayed. A uniform magnetic field is formed by the uniform magnetic field coil to magnetize the test material, but the gradient magnetic field coil has not yet been powered on. The real-time current and voltage are 0, and the magnetic field intensity gradient should also be 0 kA / m 2 ; (3) Turn on the power control switch of the gradient magnetic field coil. The gradient magnetic field coil power indicator light will light up. Rotate the gradient magnetic field coil current control knob to adjust the current input into the gradient magnetic field coil to the target value. The current display will show the real-time current and voltage in the gradient magnetic field coil. At the same time, it will show the magnetic field intensity and magnetic field intensity gradient at the center of the test space along the coil axis. (4) The saturated magnetized test material located in the test area will produce a magnetic force under the action of the gradient magnetic field. The direction of the magnetic force is the same as the direction of the magnetic flux density gradient. The magnetic force will change the force on the test material and place it in the target gravity field.

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