Magnetic fluid tuned mass damper utilizing particle collision damping

Abstract

Magnetic liquid tuned mass damper with particle collision damping belongs to the field of vibration control. It successfully solves the problem that the existing magnetic liquid tuned mass damper cannot be applied to medium and high frequency vibration. The tuned mass damper comprises a shell (1), a left return permanent magnet (2), a left supporting magnetic liquid (3), a left supporting permanent magnet (4), an inner cavity magnetic liquid (5), a right supporting magnetic liquid (6), a right supporting permanent magnet (7), a right return permanent magnet (8), a right excitation coil (9), a ball (10), a Hall element (11), a supporting shell (12), an air passage (13) and a left excitation coil (14). The tuned mass damper combines magnetic liquid damping and particle collision damping, and simultaneously introduces active control, which is not only suitable for low frequency vibration below 10 Hz, but also has effect on high frequency vibration above 100 Hz.

Description

Technical Field

[0001] This invention belongs to the field of vibration control in mechanical engineering (including machines, mechanisms and various parts under gravity and weightlessness). Background Technology

[0002] A magnetic fluid tuned mass damper is an active vibration damper, consisting of four elements: a tuned mass, a damping unit, an elastic unit, and a control unit. Common magnetic fluid tuned mass dampers use a magnetic fluid as the tuned mass, employing a coil to generate a changing magnetic field that drives the magnetic fluid to oscillate within a container, producing viscous damping to reduce vibration. However, the magnetic fluid acts as both the tuned mass and the elastic element, resulting in very low density and magnetization, leading to minimal inertial force. Furthermore, the viscous damping force of the magnetic fluid is extremely limited, resulting in existing magnetic fluid tuned mass dampers being relatively large, having a slow response speed, a very narrow operating frequency band, and poor vibration reduction performance, only showing some effect within the 10Hz range.

[0003] Regarding improving damping force, some literature has adopted methods such as increasing surface roughness and using porous media. For example, Literature 1 (patent application CN 112727972 B) increases frictional damping by texturing the contact surface of the magnetic liquid. However, the damping provided by this method cannot be automatically adjusted according to the vibration frequency, and the damping force provided by the viscous friction of the magnetic liquid is still very limited and cannot meet the requirements of high-frequency vibration. Literature 2 (patent application CN 112392887 B) adds porous media to the surface of the permanent magnet and uses a protrusion structure processed on one side of the end cap to squeeze the magnetic liquid, thereby achieving the repositioning of the permanent magnet through the change of the levitation force of the magnetic liquid. However, the levitation force of the magnetic liquid is very limited and ineffective for high frequencies. Moreover, when the external vibration frequency is high, the permanent magnet is prone to collision with the protrusion structure on the end cap, which may even cause the permanent magnet to break. References 3 (patent application CN 112392885 B), 4 (patent application CN 112392886 B), and 5 (patent application CN 112392890 B) all utilize the protruding portions at both ends of an inertial mass block to compress the magnetic fluid within a pipe, thereby dissipating energy through a porous medium. However, this damping force still falls under the category of liquid viscous damping, which has limited effectiveness and is not ideal for high-frequency vibrations. Furthermore, Reference 5's method of using compressed air to enhance the restoring force is unreliable. Reference 6 (patent application CN 114962514 B) employs impact damping, suspending a sphere within a cavity filled with magnetic fluid and equipped with an elastic cushion under the influence of an external magnetic field. Impact damping is used to improve the application frequency band, but this invention uses only one sphere, and the impact damping occurs only between the copper sphere and the cushion inside the cavity, resulting in very limited damping force. As the vibration frequency increases, the damping force of this damper will be insufficient. Therefore, there is currently a lack of a magnetic fluid tuned mass damper that can have nonlinear damping and stiffness and can be adjusted according to the vibration frequency. Summary of the Invention

[0004] The technical problem this invention aims to solve is that existing magnetic fluid tuned mass dampers suffer from very narrow operating frequency bands due to the low density and large volume of the magnetic fluid as the tuned mass, resulting in slow response speed and limited damping and elastic forces. This makes them ineffective at suppressing vibrations above 10Hz and completely ineffective at vibrations above 100Hz or even 1000Hz. This invention provides a magnetic fluid tuned mass damper utilizing particle collision damping. It utilizes the repulsive force between permanent magnets as an elastic element to provide the required nonlinear stiffness for the system, and the viscous damping force of the magnetic fluid to address low-frequency vibrations. Furthermore, by inserting non-magnetic spheres into a shell suspended by the magnetic fluid to form the tuned mass, the volume is significantly reduced compared to using the magnetic fluid as the tuned mass. This creates particle collision damping with strong nonlinear characteristics, thereby reducing the volume and solving the problem of insufficient damping force at high frequencies. The magnetic attraction and repulsion between the excitation coil and the permanent magnets enhance the response speed of the tuned mass. Therefore, this tuned mass damper has excellent vibration reduction performance, small size, and fast response, whether it is low-frequency vibration of only a few hertz or high-frequency vibration of thousands of hertz.

[0005] The technical solution adopted by this invention to solve its technical problem is: The tuned mass damper includes: a housing, a left restoring permanent magnet, a left supporting magnetic fluid, a left supporting permanent magnet, an inner cavity magnetic fluid, a right supporting magnetic fluid, a right supporting permanent magnet, a right restoring permanent magnet, a right excitation coil, a sphere, a Hall element, a supporting housing, a vent, and a left excitation coil.

[0006] An inner cavity magnetic fluid and spheres are filled into a support shell and sealed to form a particle collision damping assembly. The spheres are made of a non-magnetic metallic material with a density greater than that of the inner cavity magnetic fluid. If the sphere is solid, its metallic density must be greater than that of the inner cavity magnetic fluid; if the sphere is hollow, its equivalent density must be greater than that of the inner cavity magnetic fluid. The number of spheres is greater than one, i.e., at least two, to ensure that the spheres collide with each other after vibration, generating particle collision damping. All spheres can be the same size or a combination of large and small spheres. The diameter of the spheres is greater than 1 mm, and the largest diameter cannot exceed half the length and end face dimensions of the support shell. This prevents the spheres from being too small and densely packed, while also preventing the spheres from being too large, which would restrict their movement space within the support shell and affect the particle collision damping force. The sphere filling rate in the shell is 10%~90%. The inner cavity magnetic fluid must completely fill the support shell; no cavities are allowed. If the volume of the sphere accounts for 10% of the volume of the inner cavity of the supporting shell, then the filling rate of the magnetic fluid in the inner cavity must be 90%.

[0007] The left support permanent magnet is fixedly installed on the left end face of the support housing, and the right support permanent magnet is fixedly installed on the right end face of the support housing, forming inertial mass. Left support magnetic fluid is injected into the outer ring of the left support permanent magnet, and right support magnetic fluid is injected into the outer ring of the right support permanent magnet.

[0008] The supporting shell is made of a non-magnetic metal material, and its end face shape is the same as that of the left and right supporting permanent magnets, but its size is smaller than that of the left and right supporting permanent magnets. This maximizes the magnetic field gradient at the left and right supporting permanent magnets, and maximizes the buoyancy of the left and right supporting magnetic fluids, allowing for a greater number of spheres to be placed in the supporting shell.

[0009] The left restoring permanent magnet is installed on the left end face of the housing, and the right restoring permanent magnet is installed on the right end face. The particle collision damping assembly is installed into the inner cavity of the housing, and ventilation grooves and channels are machined on the inner wall of the housing. The housing must be well sealed to prevent the evaporation and failure of the left and right supporting magnetic fluids. The left restoring permanent magnet, left supporting permanent magnet, right supporting permanent magnet, and right restoring permanent magnet are adjacent to each other, and all adopt a magnetic pole repulsion mode between them. The magnetic repulsion force generated by the like pole repulsion has very strong nonlinear characteristics. As the distance between the two permanent magnets decreases, the magnitude of the repulsion force increases exponentially, which can provide the tuned mass damper with very high stiffness, which is extremely beneficial to improving the application bandwidth of the tuned mass damper.

[0010] The shell is made of a non-magnetic material, and the inner wall has ventilation channels along its length, with the number of channels ranging from 1 to 12. The injection volume of the left and right supporting magnetic liquids is insufficient to block all the ventilation channels, preventing changes in gas pressure between the chambers separated by the left and right supporting magnetic liquids due to inertial mass movement, thus avoiding the formation of an unstable gas elastic force.

[0011] Hall effect sensors are mounted on the outer wall of the housing to detect changes in the magnetic field and determine the displacement of the inertial mass within the housing. A single Hall effect sensor can be used, mounted at the midpoint of the housing's length, with its front and back facing the left and right supporting permanent magnets, respectively. When external vibrations cause the inertial mass to move to the left relative to the housing, the Hall effect sensor displays a higher value relative to its initial position; when it moves to the right, the display decreases. Alternatively, two Hall effect sensors can be used, placed between the left return permanent magnet and the left supporting permanent magnet, and between the right supporting permanent magnet and the right return permanent magnet, with their front faces against the housing wall. When external vibrations cause the inertial mass to move to the left relative to the housing, the left Hall effect sensor displays a higher value, while the right displays a lower value; conversely, when it moves to the right, the left displays a lower value, while the right displays a higher value. The displacement of the inertial mass can then be determined using a differential circuit.

[0012] The right excitation coil is fitted into the right end of the housing, and the left excitation coil into the left end, making them symmetrical about the midpoint of the outer wall of the housing. The right and left excitation coils are identical in size and shape, have the same number of turns, and their inner hole shape and dimensions match the outer shape and dimensions of the housing. The distances between the left supporting permanent magnet and the left excitation coil, and between the right supporting permanent magnet and the right excitation coil, must be greater than the maximum displacement of the inertial mass within the housing. This prevents the right or left supporting permanent magnet from detaching from the coil range during excitation, thus avoiding magnetic force reversal issues between the left and right excitation coils, or between the right and right excitation coils. The current intensity flowing through the right and left excitation coils varies from 0 to 10 A.

[0013] The advantages of this invention compared with existing technologies are as follows: (1) By utilizing the nonlinear characteristics of the repulsive force between permanent magnets, a large stiffness span is obtained, thus broadening the application bandwidth; (2) Non-magnetic spheres and magnetic liquid in the inner cavity are installed in the support shell to form a particle collision damping component; at the same time, by utilizing the levitation force of the magnetic liquid, the inertial mass composed of the left support permanent magnet, the right support permanent magnet and the particle collision damping component is suspended in the shell, making full use of the viscous damping force of the left support magnetic liquid and the right support magnetic liquid; through this design, the viscous damping of magnetic liquid and particle collision damping are combined, so that magnetic liquid viscous damping can be used in low-frequency vibration environment and particle collision damping can be used in high-frequency vibration environment. (3) By monitoring the magnetic field change through the Hall element, the displacement of the inertial mass can be obtained. After the data is fed back, the right excitation coil and the left excitation coil are driven to excite the motion of the inertial mass, which can achieve a good active control effect. (4) The inertial mass is composed of two permanent magnets, a supporting shell, a non-magnetic metal sphere and an inner cavity magnetic liquid. The equivalent density is much greater than the density of the magnetic liquid in the traditional magnetic liquid tuned mass damper, which is more conducive to mass tuning. (5) After the right excitation coil and the left excitation coil are energized, they form an electromagnetic force drive with the left supporting permanent magnet and the right supporting permanent magnet, which is more controllable and has a greater control force. Attached Figure Description

[0014] Figure 1 Schematic diagram of a magnetic fluid tuned mass damper that utilizes particle collision damping. In the diagram: 1. Housing; 2. Left return permanent magnet; 3. Left support magnetic fluid; 4. Left support permanent magnet; 5. Inner cavity magnetic fluid; 6. Right support magnetic fluid; 7. Right support permanent magnet; 8. Right return permanent magnet; 9. Right excitation coil; 10. Sphere; 11. Hall element; 12. Support housing; 13. Ventilation channel; and 14. Left excitation coil. Detailed Implementation

[0015] The present invention will be further described with reference to the accompanying drawings as specific embodiments: Magnetic fluid tuned mass dampers that utilize particle collision damping, such as Figure 1 The tuned mass damper includes: a housing 1, a left restoring permanent magnet 2, a left supporting magnetic fluid 3, a left supporting permanent magnet 4, an inner cavity magnetic fluid 5, a right supporting magnetic fluid 6, a right supporting permanent magnet 7, a right restoring permanent magnet 8, a right excitation coil 9, a sphere 10, a Hall element 11, a supporting housing 12, a vent 13, and a left excitation coil 14.

[0016] The inner cavity magnetic fluid 5 and the spheres 10 are placed into the support shell 12 and sealed to form a particle collision damping assembly. The spheres 10 are made of a non-magnetic metallic material with a density greater than that of the inner cavity magnetic fluid 5. If the spheres 10 are solid, their metallic density must be greater than that of the inner cavity magnetic fluid 5; if the spheres 10 are hollow, their equivalent density must be greater than that of the inner cavity magnetic fluid 5. The number of spheres 10 is greater than one, i.e., at least two, to ensure that the spheres 10 will collide with each other after vibration, generating particle collision damping. All spheres 10 can be of the same size or a combination of large and small spheres. The diameter of the spheres 10 is greater than 1 mm, and the largest diameter cannot exceed half the length and end face dimensions of the support shell 12. This prevents the spheres 10 from being too small and densely packed, while also preventing the spheres 10 from being too large, which would restrict their movement space within the support shell 12 and affect the particle collision damping force between the spheres 10. The filling rate of spheres 10 in the support shell 12 is 10%~90%. Larger spheres 10 are more sensitive to low-frequency vibrations, while smaller spheres 10 have greater damping force for high-frequency vibrations; the selection should be based on the specific vibration conditions. If the vibration frequency is relatively uniform, and the vibration frequency of the object being damped is only tens of hertz, the number of spheres 10 should be reduced, preferably to less than 10, while increasing the size of the spheres 10. If the vibration frequency is relatively uniform and greater than 100 Hz, the number of spheres 10 should be increased as the vibration frequency increases, while decreasing the size of the spheres 10. If the vibration frequency range of the object being damped is large, large and small spheres 10 can be mixed in a certain proportion by volume fraction. The inner cavity magnetic fluid 5 must be completely filled in the support shell 12; no cavities are allowed. If the volume of spheres 10 accounts for 10% of the inner cavity volume of the support shell 12, then the filling rate of the inner cavity magnetic fluid 5 must be 90%.

[0017] The left supporting permanent magnet 4 is fixedly installed on the left end face of the supporting housing 12, and the right supporting permanent magnet 7 is fixedly installed on the right end face of the supporting housing 12, forming inertial mass. Left supporting magnetic fluid 3 is injected into the outer ring of the left supporting permanent magnet 4, and right supporting magnetic fluid 6 is injected into the outer ring of the right supporting permanent magnet 7.

[0018] The supporting shell 12 is made of a non-magnetic metal material, and its end face shape is the same as that of the left supporting permanent magnet 4 and the right supporting permanent magnet 7, but its size is smaller than that of the left supporting permanent magnet 4 and the right supporting permanent magnet 7. This maximizes the magnetic field gradient at the left supporting permanent magnet 4 and the right supporting permanent magnet 7, and maximizes the buoyancy of the left supporting magnetic liquid 3 and the right supporting magnetic liquid 6, thus allowing for a greater number of spheres 10 to be placed in the supporting shell 12.

[0019] The left restoring permanent magnet 2 is installed on the left end face of the housing 1, and the right restoring permanent magnet 8 is installed on the right end face of the housing 1. The particle collision damping assembly is installed in the inner cavity of the housing 1, and a vent 13 is machined on the inner wall of the housing 1. The housing 1 must be well sealed to prevent the left supporting magnetic liquid 3 and the right supporting magnetic liquid 6 from evaporating and failing. The left restoring permanent magnet 2, the left supporting permanent magnet 4, the right supporting permanent magnet 7, and the right restoring permanent magnet 8 are adjacent to each other, and all adopt a magnetic pole repulsion mode between them. The magnetic repulsion force generated by the like pole repulsion has very strong nonlinear characteristics. As the distance between the two permanent magnets decreases, the magnitude of the repulsion force increases exponentially, which can provide the tuned mass damper with very high stiffness, which is extremely beneficial to improving the application bandwidth of the tuned mass damper.

[0020] The shell 1 is made of a non-magnetic material, and its inner wall is machined with ventilation channels 13 along its length. The number of ventilation channels 13 is 1 to 12. The injection volume of the left supporting magnetic liquid 3 and the right supporting magnetic liquid 6 is insufficient to block all the ventilation channels 13, preventing changes in gas pressure between the chambers separated by the left supporting magnetic liquid 3 and the right supporting magnetic liquid 6 due to inertial mass movement, thus avoiding the formation of an unstable gas elastic force. The shell 1 must be completely sealed to prevent the evaporation of the left supporting magnetic liquid 3 and the right supporting magnetic liquid 6. The outer shell shape of the shell 1 can be cylindrical, cuboid, or cube.

[0021] Hall element 11 is mounted on the outer wall of housing 1 to detect changes in the magnetic field and determine the displacement of the inertial mass within housing 1. A single Hall element 11 can be used, mounted at the midpoint of the length of housing 1, with its front and back facing the left supporting permanent magnet 4 and right supporting permanent magnet 7, respectively. When external vibrations cause the inertial mass to move to the left relative to housing 1, the Hall element 11 displays a value that increases relative to its initial position; when external vibrations cause the inertial mass to move to the right relative to housing 1, the Hall element displays a value that decreases relative to its initial position. Alternatively, two Hall elements 11 can be used, placed between the left restoring permanent magnet 2 and the left supporting permanent magnet 4, and between the right supporting permanent magnet 7 and the right restoring permanent magnet 8, with the front faces of both Hall elements 11 attached to the wall of housing 1. When external vibrations cause the inertial mass to move to the left relative to the shell 1, the value displayed by the Hall element on the left will increase, and the value displayed by the Hall element on the right will decrease; when external vibrations cause the inertial mass to move to the right relative to the shell 1, the value displayed by the Hall element on the left will decrease, and the value displayed by the Hall element on the right will increase. The displacement of the inertial mass can be obtained through a differential circuit.

[0022] The right excitation coil 9 is fitted into the right end of the housing 1, and the left excitation coil 14 is fitted into the left end of the housing 1, making the right excitation coil 9 and the left excitation coil 14 symmetrical about the midpoint of the length of the outer wall of the housing 1. The right excitation coil 9 and the left excitation coil 14 are exactly the same in size and shape, have the same number of turns, and the shape and size of their inner holes are the same as the outer shape and size of the housing 1. The distance between the left supporting permanent magnet 4 and the left excitation coil 14, and the distance between the right supporting permanent magnet 7 and the right excitation coil 9, must be greater than the maximum displacement of the inertial mass within the housing 1. This is to prevent the right supporting permanent magnet 7 or the left supporting permanent magnet 4 from detaching from the coil range during excitation drive, thus preventing magnetic force reversal between the left excitation coil 14 and the left supporting permanent magnet 4, and between the right excitation coil 9 and the right supporting permanent magnet 7. The current intensity of the right excitation coil 9 and the left excitation coil 14 varies from 0 to 10A.

[0023] After vibration occurs, if the vibration frequency is below 10Hz, under the influence of the viscous damping force of the left supporting magnetic fluid 3 and the right supporting magnetic fluid 6, the inertial mass composed of the particle collision damping component, the left supporting permanent magnet 4, and the right supporting permanent magnet 7 will undergo relative motion with the shell 1, consuming the vibration energy of the system. During this process, due to the small inertial force, the sphere 10 basically does not move within the supporting shell 12, and no particle collision damping occurs. The damping force of the system mainly comes from the viscous damping force of the left supporting magnetic fluid 3 and the right supporting magnetic fluid 6. In addition, at this time, the magnetic repulsion force between the left recovering permanent magnet 2 and the left supporting permanent magnet 4, and between the right supporting permanent magnet 7 and the right recovering permanent magnet 8 is also very small, and the force-displacement relationship is close to linear. As the vibration frequency increases, the magnetic repulsion force between the left recovering permanent magnet 2 and the left supporting permanent magnet 4, and between the right supporting permanent magnet 7 and the right recovering permanent magnet 8 begins to increase, and the nonlinear relationship between force and displacement increases. The inertial force on the particle collision damping component also begins to increase, and the sphere 10 begins to undergo limited collision motion within the supporting shell 12, generating a certain amount of particle collision damping. At this time, the vibration energy of the system will be consumed by the viscous damping force of the left supporting magnetic fluid 3 and the right supporting magnetic fluid 6, as well as the particle collision damping force. If the vibration frequency further increases, even reaching thousands of hertz, the magnetic repulsion force between the left restoring permanent magnet 2 and the left supporting permanent magnet 4, and between the right supporting permanent magnet 7 and the right restoring permanent magnet 8, reaches its maximum, and the force-displacement relationship exhibits extremely strong nonlinearity. In terms of damping, the collision of the sphere 10 with the supporting shell 12 is very significant, and particle collision damping will play an absolutely dominant role. The viscous damping force of the left supporting magnetic fluid 3 and the right supporting magnetic fluid 6 has a negligible impact on the loss of vibration energy.

[0024] If the external control system detects poor vibration suppression through Hall element 11, it initiates active control, energizing the left excitation coil 14 and the right excitation coil 9. When the inertial mass moves towards the left end of the housing 1, an attractive force needs to be generated between the left excitation coil 14 and the left supporting permanent magnet 4, while a repulsive force needs to be generated between the right excitation coil 9 and the right supporting permanent magnet 7. Therefore, the current should be applied so that the magnetic poles of the left excitation coil 14 and the left supporting permanent magnet 4 are opposite, while the magnetic poles of the right excitation coil 9 and the right supporting permanent magnet 7 are the same. Conversely, when the inertial mass moves towards the right end of the housing 1, the current direction reverses.

[0025] The left-supporting magnetic fluid 3, the inner cavity magnetic fluid 5, and the right-supporting magnetic fluid 6 shall be kerosene-based, oil-based, or ester-based magnetic fluids, with a viscosity not exceeding 500 mPa·s. Similar magnetic fluids, such as magnetorheological fluids, cannot be substituted. The left-supporting magnetic fluid 3 and the right-supporting magnetic fluid 6 must be the same type of magnetic fluid, while the inner cavity magnetic fluid 5 can be of a different type.

[0026] The left-returning permanent magnet 2, the left-supporting permanent magnet 4, the right-supporting permanent magnet 7, and the right-returning permanent magnet 8 can be made of neodymium iron boron or samarium cobalt permanent magnet materials depending on the temperature environment.

[0027] The above is merely an example of the implementation of the present invention and is not intended to limit the present invention. For those skilled in the art, the particle collision damper based on the magnetic liquid suspension characteristics can be modified according to the engineering situation, including but not limited to the size of the damper, the volume ratio of each part of the sphere, the shell shape, the material selection, the installation position, etc., to adapt to the corresponding engineering.

Claims

1. A magnetic fluid tuned mass damper utilizing particle collision damping, characterized by: The tuned mass damper includes: a housing (1), a left restoring permanent magnet (2), a left supporting magnetic fluid (3), a left supporting permanent magnet (4), an inner cavity magnetic fluid (5), a right supporting magnetic fluid (6), a right supporting permanent magnet (7), a right restoring permanent magnet (8), a right excitation coil (9), a sphere (10), a Hall element (11), a supporting housing (12), a vent (13), and a left excitation coil (14); The inner cavity magnetic liquid (5) and the spheres (10) are loaded into the support shell (12) and sealed to form a particle collision damping assembly, wherein the number of the spheres (10) is greater than 1. The left support permanent magnet (4) is fixedly installed on the left end face of the support shell (12), and the right support permanent magnet (7) is fixedly installed on the right end face of the support shell (12) to form inertial mass; Left support magnetic liquid (3) is injected into the outer ring of the left support permanent magnet (4), and right support magnetic liquid (6) is injected into the outer ring of the right support permanent magnet (7); the left support magnetic liquid (3), the inner cavity magnetic liquid (5) and the right support magnetic liquid (6) are magnetic liquids with a viscosity not higher than 500 mPa·s, and the magnetic liquids are not magnetorheological fluids; the left support magnetic liquid (3) and the right support magnetic liquid (6) are the same type of magnetic liquid, and the inner cavity magnetic liquid (5) is the same or different type of magnetic liquid; Install the left return permanent magnet (2) on the left end face of the housing (1), and install the right return permanent magnet (8) on the right end face of the housing (1); The Hall element (11) is mounted on the outer wall of the housing (1); Insert the right excitation coil (9) into the right end of the housing (1) and the left excitation coil (14) into the left end of the housing (1), so that the right excitation coil (9) and the left excitation coil (14) are symmetrical about the midpoint of the length of the outer wall of the housing (1). When the left excitation coil (14) and the right excitation coil (9) are energized, if the inertial mass moves to the left end of the housing (1), the left excitation coil (14) needs to generate an attractive force between itself and the left supporting permanent magnet (4), and the right excitation coil (9) needs to generate a repulsive force between itself and the right supporting permanent magnet (7). Therefore, the current should make the magnetic poles of the left excitation coil (14) and the left supporting permanent magnet (4) opposite, and the magnetic poles of the right excitation coil (9) and the right supporting permanent magnet (7) the same. Conversely, when the inertial mass moves to the right end of the housing (1), the direction of the current is reversed. The particle collision damping assembly is installed in the inner cavity of the housing (1), and an air passage (13) is machined on the inner wall of the housing (1).

2. The magnetic fluid tuned mass damper utilizing particle collision damping according to claim 1, characterized by: The supporting shell (12) is made of non-magnetic metal material, and its end face shape is the same as that of the left supporting permanent magnet (4) and the right supporting permanent magnet (7), and its size is smaller than that of the left supporting permanent magnet (4) and the right supporting permanent magnet (7).

3. The magnetic fluid tuned mass damper utilizing particle collision damping according to claim 1, characterized by: The sphere (10) is made of a non-magnetic metal material with a density greater than that of the magnetic liquid (5) in the inner cavity; the diameter of the sphere (10) is greater than 1 mm, and the maximum diameter cannot exceed 1 / 2 of the length and end face dimensions of the supporting shell (12).

4. The magnetic fluid tuned mass damper utilizing particle collision damping according to claim 1, characterized by: The left return permanent magnet (2), the left support permanent magnet (4), the right support permanent magnet (7) and the right return permanent magnet (8) are adjacent to each other and all adopt the same pole repulsion magnetic pole mode.

5. The magnetic fluid tuned mass damper utilizing particle collision damping according to claim 1, characterized by: The shell (1) is made of non-magnetic material, and the inner wall is processed with ventilation channels (13) along its length. The number of ventilation channels (13) is 1 to 12. The injection amount of the left supporting magnetic liquid (3) and the right supporting magnetic liquid (6) cannot block all the ventilation channels (13).

6. The magnetic fluid tuned mass damper utilizing particle collision damping according to claim 1, characterized by: The right excitation coil (9) and the left excitation coil (14) are exactly the same in size and shape, and have the same number of turns. The shape and size of the inner hole are the same as the outer shape and size of the shell (1). The distance between the left support permanent magnet (4) and the left excitation coil (14), and the distance between the right support permanent magnet (7) and the right excitation coil (9) are both greater than the maximum displacement of the inertial mass in the shell (1).

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