A tuned magnetic liquid rolling ball damper

Abstract

The present invention is a tuned magnetic liquid rolling ball damper. The damper comprises a cylindrical container with a hemispherical groove, a cylindrical solenoid coil, a horizontal base, a hollow rolling ball and a kerosene-based magnetic liquid; wherein the cylindrical solenoid coil is evenly wound on the outer wall of the cylindrical container body, the cylindrical container is located on the horizontal base, and the hollow rolling ball has a kerosene-based magnetic liquid inside; the hollow rolling ball is in the hemispherical groove in the cylindrical container. The kerosene-based magnetic liquid is a kerosene-based Fe3O4 magnetic liquid, and its volume is 1 / 4 to 3 / 4 of the volume inside the spherical shell. The present invention has the advantages of simple structure, low cost, easy control and wide working frequency band.

Description

Technical Field

[0001] The invention relates to a damper, mainly to a tuned magnetic liquid rolling ball damper. Background Art

[0002] Tuned dampers are widely used in various tall structures. As a tall structure, wind turbine towers are slender, flexible, low in stiffness, and easy to fatigue. During operation, they will vibrate due to factors such as wind loads, seismic loads, and power system disturbances. Vibration is one of the important factors affecting the life of wind turbines. Vibration problems can cause blade fractures, excessive nacelle amplitude, tower instability, generator failure, and other phenomena, resulting in the inability of wind turbines to work properly, and may even cause tower collapse accidents, resulting in significant losses. Therefore, the research on vibration control of wind turbine towers has important theoretical significance and engineering practical value. This patent intends to develop a device to reduce the vibration of the structure under wind loads from the two aspects of reducing the frequent vibration and response of the wind turbine tower structure.

[0003] Currently, the existing tuned dampers mainly include tuned mass dampers, tuned liquid dampers, and tuned rolling ball dampers. The tuned mass damper is composed of a spring and a mass block. The purpose of tuning vibration reduction is achieved by changing the spring elastic coefficient and the mass of the mass block; the tuned liquid damper is to put a certain amount of liquid in a rectangular or cylindrical container, and achieve the purpose of tuning vibration reduction by changing the liquid depth; the tuned rolling ball damper is to put a certain number of small balls in a spherical container, and achieve the purpose of tuning vibration reduction by changing the number and radius of the small balls. These dampers usually change the spring elastic coefficient and the mass of the mass block, or change the depth and viscosity of the liquid to adjust the natural sway frequency of the damper, change the resonance characteristics of the entire structure, and thus achieve the effect of tuned damping vibration reduction; most of these dampers have obvious effects on the natural frequency of the first vibration mode of the structure, and the vibration reduction frequency band is narrow; when the external load disturbance is more complex, the shock absorption effect is significantly reduced, and the controllability is poor. Summary of the invention

[0004] The purpose of the present invention is to provide a tuned magnetic liquid rolling ball damper to address the deficiencies of the prior art. The damper cleverly combines a rolling ball damper with a tuned magnetic liquid rolling ball damper, and magnetic liquid is placed in a small ball, so that the small ball drives the magnetic liquid to roll together. The damper's natural frequency can be changed not only by changing the radius of the small ball and the container, but also by adjusting the external magnetic field to change the sloshing frequency of the magnetic liquid to change the damper's natural frequency, thereby achieving the purpose of dual-tuned vibration reduction. The present invention has the advantages of simple structure, low cost, easy control and wide working frequency band.

[0005] The technical solution of the present invention is:

[0006] A tuned magnetic liquid rolling ball damper comprises a cylindrical container with a hemispherical groove, a cylindrical solenoid coil, a horizontal base, a hollow rolling ball and a kerosene-based magnetic liquid; wherein the cylindrical solenoid coil is evenly wound on the outer wall of the cylindrical container body, the cylindrical container is located on the horizontal base, and the hollow rolling ball contains kerosene-based magnetic liquid; the hollow rolling ball is in the hemispherical groove in the cylindrical container.

[0007] The upper part of the cylindrical container is an open hemispherical groove, the top of the groove is a protruding upper edge of the shell, and the bottom of the cylindrical container is a protruding horizontal base;

[0008] The hollow rolling ball is a hollow sphere; a screw hole equipped with a threaded plug is provided on the top of the shell; the shell thickness of the hollow rolling ball is 8-12 mm; and the material is a resin material.

[0009] The radius of the hollow rolling ball is 1 / 12 to 1 / 8 of the radius of the groove;

[0010] The cylindrical solenoid coil is a copper core enameled wire, which is wound with 4 to 7 layers in total and has a rated current of 5A.

[0011] The kerosene-based magnetic liquid is a kerosene-based Fe3O4 magnetic liquid with a density of 1.36 g / cm 3 The ferroferric oxide is a nanoparticle with a diameter ranging from 2 to 20 nm. The volume of the kerosene-based magnetic liquid is 1 / 4 to 3 / 4 of the internal volume of the spherical shell.

[0012] The horizontal base is evenly distributed with fixing screw holes along the circumference.

[0013] The outer shell diameter of the cylindrical main body ranges from 0.65m to 1.45m, and the radius of the inner hemispherical groove ranges from 0.3m to 0.7m.

[0014] The essential features of the present invention are:

[0015] The present invention studies and designs the geometric dimensions of a hemispherical container and a rolling ball according to the vibration intensity and frequency of the structure, fills a kerosene-based magnetic liquid in the small ball, and combines the magnetic-viscous properties of the magnetic liquid to adjust the external magnetic field by changing the current passed through the solenoid coil to change the viscosity of the magnetic liquid, thereby adjusting the natural frequency of the damper and changing the resonance characteristics of the entire structure, thereby achieving the purpose of adaptive variable frequency vibration control.

[0016] Beneficial effects of the present invention:

[0017] 1. The present invention overcomes the technical problem of uncontrollable frequency of traditional tuned liquid dampers. It only needs to adjust the input current of the controllable current source to control the natural frequency of the damper and change the resonance characteristics of the structure to achieve the purpose of tuning and vibration reduction, and has good controllability.

[0018] 2. At present, most of the tuned dampers used in high-rise structures at home and abroad can only play a tuning and vibration reduction effect on vibrations within the range of 0.25Hz around the natural frequency of the structure. Due to the performance parameters such as the rolling ball and the inertial viscosity of the magnetic fluid, the present invention can tune and reduce vibrations within the range of 0.32Hz around the natural frequency of the high-rise structure by adjusting the external magnetic field, and the vibration reduction bandwidth is increased by 0.14Hz.

[0019] 3. The present invention can adjust the natural frequency of the damper by changing the radius of the ball and the container, and can also adjust the natural frequency of the damper by changing the sloshing frequency of the magnetic liquid by changing the external magnetic field, and has the function of double tuning vibration reduction.

[0020] 4. In the present invention, the rolling ball drives the internal liquid to roll together, so that the liquid is in a turbulent state under working conditions. Experiments have shown that compared with the sloshing state of the liquid in a fixed container, the liquid in a turbulent state has greater kinetic energy, that is, the disturbance of the liquid is increased, thereby achieving the purpose of increasing energy consumption; at the same time, the friction between the ball and the wall when rolling can also increase the consumption of vibration energy.

[0021] 5. The present invention has a simple structure, and is composed of only a hollow ball, a cylindrical container with a hemispherical groove, a cylindrical solenoid coil, a horizontal base and a kerosene-based magnetic liquid. It is easy to process, low in cost, easy to maintain and cost-effective.

[0022] 6. The present invention can reduce the shaking of the structure in any horizontal direction, has the function of multi-directional vibration reduction, has strong adaptability, and can be applied to tall building structures such as wind power towers and TV towers. It has a wide range of applications and can produce good economic and social benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the overall appearance structure of the tuned magnetic liquid rolling ball damper of the present invention;

[0024] Figure 2 It is a schematic diagram of the overall cross-sectional structure of the tuned magnetic liquid rolling ball damper of the present invention;

[0025] Figure 3 It is a schematic diagram of the overall cross-sectional structure of a cylindrical container with a hemispherical groove inside the tuned magnetic liquid rolling ball damper of the present invention;

[0026] Figure 4It is a schematic diagram of the winding structure of a cylindrical solenoid coil of a tuned magnetic liquid rolling ball damper of the present invention;

[0027] Figure 5 A schematic diagram of the structure of a hollow ball of a tuned magnetic liquid ball damper of the present invention;

[0028] Figure 6 The figure is a curve diagram of the change of magnetic flux density along the cross section of the hemispherical groove surface in the tuned magnetic liquid rolling ball damper of the present invention.

[0029] In the figure, 1. a cylindrical container with a hemispherical groove inside, 2. a cylindrical solenoid coil, 3. a horizontal base, 4. a hollow ball, 5. a kerosene-based magnetic liquid, 1-1. an upper edge of a cylindrical container, 1-2. a main shell of a cylindrical container, 1-3. a hemispherical groove, 2. a cylindrical solenoid coil, 3-1. a threaded hole on a horizontal base, 3-2. a cylindrical horizontal base, 4-1. a hollow spherical shell, 4-2. a threaded hole, 4-3. a threaded plug. DETAILED DESCRIPTION

[0030] Specific embodiments of the present invention are given below.

[0031] The composition of the tuned magnetic liquid rolling ball damper of the present invention is as follows: Figure 1 As shown, it includes a cylindrical container 1 with a hemispherical groove, a cylindrical solenoid coil 2, a horizontal base 3, a hollow ball 4, and a kerosene-based magnetic liquid 5; wherein the cylindrical solenoid coil 2 is evenly wound on the wall surface of the main shell of the cylindrical container 1, the cylindrical container 1 is located on the horizontal base 3, and the hollow ball 4 has kerosene-based magnetic liquid 5 inside; the hollow ball 4 is in the hemispherical groove in the cylindrical container 1.

[0032] The cylindrical container 1 is as follows Figure 2 As shown, the upper part is an open hemispherical groove 1-3, the top of the groove is a protruding shell upper edge 1-1, and the bottom of the cylindrical container 1 is a protruding horizontal base 3; the solenoid coil 2 is evenly wound on the wall surface between the shell upper edge 1-1 and the base 3 of the cylindrical container main body shell 1-2, forming the shell structure of the entire damper; wherein, the diameter of the cylindrical container main body shell 1-2 is 10 cm larger than the diameter of the hemispherical groove 1-3, and its height is 20 cm larger than the radius of the hemispherical groove.

[0033] The hollow rolling ball 4 can roll in any direction on the hemispherical groove surface 1-3, driving the internal kerosene-based magnetic liquid 5 to roll together, and can damp and reduce vibration of shaking in any direction in the horizontal direction.

[0034] The cylindrical container 1 and the base 3 are integrated as a whole and can be processed by factory model casting or 3D printing.

[0035] The hollow ball 4 is as follows Figure 5 As shown, it is a rollable thin-walled spherical shell made of ABS resin material with a wall thickness of 10mm; there is a cylindrical threaded hole 4-2 with a diameter of about 8.5mm on the top of the shell, which is used to load and take out kerosene-based magnetic liquid 5, and is equipped with a corresponding model of ABS resin material threaded plug 4-3 to ensure that it is screwed in and sealed to form a closed spherical shell that can roll in any direction on the hemispherical groove surface.

[0036] The relationship between the radius of the hollow rolling ball and the radius of the hemispherical groove is:

[0037] Among them, f is the natural frequency of the damper system. For wind turbine towers, the frequency limit that can reduce vibration is 1.37 Hz, g is the acceleration of gravity, R is the radius of the hemispherical groove, and r is the radius of the hollow rolling ball.

[0038] The radius of the hollow ball is 1 / 12 to 1 / 8 of the radius of the groove; the difference in radius between the two can be calculated from the vibration damping frequency, and then the mass of the damper and the volume of the magnetic fluid can be determined based on the modal mass ratio of the damper to the vibration structure, and then the radius of the groove and the ball can be determined.

[0039] The ball cannot protrude from the shell. After analysis and calculation, the radius of the ball will not exceed 1 / 8 of the radius of the groove. The force analysis and calculation of the ball motion state in the extreme case (the ball radius is 1 / 8 of the groove radius) are carried out. When the external given acceleration is 32m / s 2 When the ball rises to the highest point, the distance between the ball and the edge of the groove is 1 / 10 of the ball's radius.

[0040] The cylindrical solenoid coil 2 is as follows Figure 4 The copper core enameled wire is shown, which is tightly wound in a single layer from bottom to top along the outside of the cylindrical container body 1-2 to a position 0.5 to 1.5 cm away from the outer edge of the upper part of the shell. A total of 4 to 7 layers are wound to form a solenoid coil with a rated current of 5A. An approximately uniform external magnetic field can be generated in the cylindrical container.

[0041] The kerosene-based magnetic liquid 5 is a kerosene-based Fe3O4 magnetic liquid with a density of 1.36 g / cm 3 The ferroferric oxide is a nanoparticle with a diameter ranging from 2 to 20 nm. The kerosene-based magnetic liquid does not completely fill the ball housing 4-1, and the volume of the injected magnetic liquid is 1 / 4 to 3 / 4 of the internal volume of the ball housing, and the ball rolls on the hemispherical groove surface 1-3 in an approximately uniform external magnetic field.

[0042] The horizontal base 3 is as follows Figure 3As shown, a cylindrical horizontal base 3-2 is provided with three threaded holes 3-1 evenly distributed along the circumference for fixing the damper on the vibration structure.

[0043] The design mechanism of the present invention is as follows: according to the vibration intensity and frequency of the structure, the geometric dimensions of the container and the rolling ball are designed, and magnetic liquid is filled in the rolling ball. When an external magnetic field acts on the magnetic liquid, the viscosity of the magnetic liquid will change with the magnetic field. Therefore, the inherent shaking frequency of the magnetic liquid can be changed by adjusting the external magnetic field, thereby controlling the inherent shaking frequency of the damping, changing the resonance characteristics of the entire structure, and achieving the purpose of tuning and vibration reduction.

[0044] The present invention is further described in detail below with reference to the embodiments and drawings.

[0045] Example 1

[0046] like Figure 1 As shown, the overall appearance structure of the tuned magnetic liquid rolling ball damper of the present invention includes a cylindrical container 1 with a hemispherical groove, a cylindrical solenoid coil 2, a horizontal base 3 and a hollow rolling ball 4; the copper core enameled wire is compressed and wound on the wall surface of the outer shell of the cylindrical container body to form the solenoid coil 2.

[0047] like Figure 2 As shown in the figure, the overall cross-sectional structure of the tuned magnetic liquid rolling ball damper of the present invention, the hollow rolling ball 3 is filled with kerosene-based magnetic liquid 5, the volume of the injected magnetic liquid is 1 / 2 of the volume of the inner part of the spherical shell, and the hollow rolling ball can drive the magnetic liquid to roll along the wall of the groove. The magnetic liquid 5 described in the figure is kerosene-based Fe3O4 magnetic liquid with a density of about 1.36g / cm 3 , viscosity is 6.63mPa·s, saturation magnetization is 513.7Gs, wherein the ferrosoferric oxide is a nanoparticle with a diameter ranging from 2 to 20nm.

[0048] like Figure 3 As shown, the overall shell cross-sectional structure of the tuned magnetic liquid ball damper of the present invention, the diameter of the cylindrical container main body shell 1-2 is 110cm, the radius of the internal hemispherical groove 1-3 is 50cm, the top is the shell upper edge 1-1, which protrudes 10cm from the shell wall and has a thickness of 5cm, and the bottom is the damper base 3-2, which has a diameter of 150cm and a thickness of 10cm. There are three threaded holes with a diameter of about 8.5mm evenly distributed on the circumference of the base with a radius of 130cm, which are used to fix the damper on the vibration structure.

[0049] like Figure 4As shown, the overall structure of the cylindrical solenoid coil of the tuned magnetic liquid rolling ball damper of the present invention is made by tightly pressing and winding a copper core enameled wire with a wire diameter of about 1.1mm outside the cylindrical container main body 1-2 to form the cylindrical solenoid coil shown in the figure. The cylindrical solenoid coil is a solenoid with a copper core enameled wire with a copper core diameter of about 1mm, which is wound from bottom to top along the cylindrical container shell in 5 layers with about 80 turns per layer, and a total number of turns of 400 turns. According to international regulations, the long-term load current allowed for 1 square millimeter copper core wire is 6A to 8A. In order to leave a safety margin, the rated working current does not exceed 5A.

[0050] like Figure 5 As shown in the figure, the overall structure of the hollow ball of the tuned magnetic liquid ball damper of the present invention, the hollow ball 2 is a rollable thin-walled spherical shell made of ABS resin material, with a wall thickness of 10mm and a diameter of 12cm; a cylindrical threaded hole 4-2 with a diameter of about 8.5mm is provided on the top of the shell body for loading and taking out kerosene-based magnetic liquid 5, and a threaded plug 4-3 of ABS resin material of a corresponding model is provided to ensure that it is screwed in and sealed to form a closed spherical shell, which can roll in any direction on the hemispherical groove surface.

[0051] like Figure 6 As shown, the magnetic flux density change curve along the cross section of the hemispherical groove surface in the tuned magnetic liquid rolling ball damper of the present invention is shown in the figure, which is the magnetic flux density change curve along the cross section of the groove when a 4A DC current is passed through the solenoid coil. The magnetic flux density changes by about 175Gs to 260Gs. The magnetic flux density required for the viscosity change of the kerosene-based magnetic liquid 5 is 40Gs to 300Gs, which meets the magnetic field requirements required for the viscosity change of the kerosene-based magnetic liquid. Therefore, changing the magnitude of the current passed through the solenoid coil can effectively adjust the viscosity of the kerosene-based magnetic liquid, thereby changing the resonance characteristics of the entire structure and achieving tuning vibration reduction.

[0052] The invention has the following advantages: firstly, compared with the traditional tuned liquid damper, the rolling ball drives the magnetic liquid to roll together, so that the magnetic liquid is quickly in a turbulent state, which increases the rapid dissipation of the structural vibration energy and can greatly reduce the amount of liquid, especially the magnetic liquid; at the same time, the rolling friction of the small ball also increases the dissipation of the structural vibration energy; compared with the tuned rolling ball damper and the tuned mass damper, the controllability is increased, and the damping frequency of the damper can be changed by applying an external magnetic field; compared with most tuned dampers, the damping frequency band of the damper is wider, the damping frequency band is increased by 0.14Hz, and the original damping frequency band is increased by 56%, which is a considerable improvement; at the same time, in the test of the wind power tower experimental model, when the mass of the damper is 1.5% to 2.5% of the first-order modal mass of the vibration structure experimental model, the standard deviation of the tower top displacement can be reduced by 20% to 42%, which can effectively reduce the vibration response and fatigue damage of the wind power tower structure and extend the service life of the wind power tower.

[0053] The damper is a tuned damper. The sway frequency of the damper can be adjusted according to the natural frequency of different buildings. To adjust the sway frequency of the damper: according to the natural frequency of the vibrating structure and the modal mass ratio of the damper to the vibrating structure, the radius of the container and the radius of the ball and the mass of the magnetic liquid are determined. When the structure is subjected to complex external disturbances, the natural frequency will be offset. At this time, the external magnetic field can be changed. For the same type of tall structures, such as wind turbine towers, the first-order natural frequencies of different wind turbine towers are relatively small. Therefore, after the geometric dimensions of the damper are determined, it can be mass-produced. It can be applied to the same type of tall structures by only adjusting the external magnetic field.

[0054] After analysis and calculation, the radius of the rolling ball will not exceed 1 / 8 of the radius of the groove. The force analysis and calculation of the rolling ball motion state in the extreme case (the rolling ball radius is 1 / 8 of the groove radius) are carried out. When the external given acceleration is 32m / s 2 When the ball can rise to the highest point, the distance between the ball and the edge of the groove is 1 / 10 of the ball radius; when the wind turbine tower is subjected to an acceleration of 20m / s 2 When there is an external disturbance, the alarm state will be triggered. Therefore, the ball will not fall within the range of external disturbance that the wind turbine tower can withstand.

[0055] According to the different sizes and heights of the attachments, the size difference between the damper groove radius and the rolling ball radius can be analyzed and calculated based on the first-order natural vibration frequency of the attachments. Then, the geometric dimensions of the damper and the volume of the magnetic fluid can be determined based on the modal mass ratio of the damper to the attachments. When the attachments are subjected to different external disturbances, the magnitude of the current passed through the solenoid coil is adjusted according to the vibration frequency deviation, the natural frequency of the damper is changed, and the resonance characteristics are adjusted to achieve the purpose of tuning and vibration reduction.

[0056] Wind turbine tower refers to the wind power generation tower. The damper is installed at the top of the wind turbine tower, which is in a semi-enclosed space. Therefore, the open design will not allow foreign objects or even rain to fall in. The same is true for other tall structures. The damper is generally installed at the top of the structure, so no foreign objects will fall in.

[0057] The application method of the tuned magnetic liquid rolling ball damper is characterized by comprising the following steps:

[0058] 1. According to the vibration intensity and frequency of the structure, a certain volume of kerosene-based magnetic liquid is filled into the ball, and the screw plug is screwed in to seal it to ensure that the magnetic liquid will not leak when the ball rolls.

[0059] 2. Make a cylindrical solenoid coil. Wind the copper core enameled wire tightly in a single layer from bottom to top along the outside of the cylindrical container body to a position 0.5 to 1.5 cm away from the upper outer edge of the shell, with a total of 4 to 7 layers.

[0060] 3. Place the assembled damper on the horizontal plane of the vibration structure, and fix the damper to the vibration structure through the threaded holes on the horizontal base, and place the rolling ball assembled with magnetic fluid at the bottom of the hemispherical groove.

[0061] 4. Connect the two terminals of the solenoid coil at the bottom of the device to the output terminals of the DC current source, turn on the DC current source, slowly increase the current, control the adjustable current input by the current source into the solenoid coil to control the shaking frequency of the damper, change the structural resonance characteristics, and achieve tuned vibration reduction.

[0062] Through the above embodiments, we can summarize the following features of the present invention:

[0063] 1. The energized solenoid coil is wound in a cylindrical design structure, which can effectively improve the uniformity of the magnetic field distribution in the cylindrical container, thereby achieving better linearity between the input current signal and the viscosity of the magnetic liquid.

[0064] 2. Compared with the traditional tuned liquid damper that changes the natural sloshing frequency by changing the liquid depth or the geometric dimensions of the container, the present invention improves the control method by controlling the viscosity of the magnetic liquid by adjusting the DC current input to the solenoid coil, thereby controlling the natural frequency of the sloshing liquid and achieving the purpose of tuning and vibration reduction.

[0065] 3. Compared with the traditional tuned mass damper that changes the natural frequency by changing the mass of the mass block or the spring elastic coefficient, the present invention adopts a container with a hemispherical groove surface. The natural frequency of the damper can be changed by designing the geometric dimensions of the small ball and the hemispherical groove. The kerosene-based magnetic liquid is used as part of the mass block. Controlling the natural sway frequency of the magnetic liquid in the spherical shell can also change the natural frequency of the damper, thereby realizing dual tuning capability.

[0066] 4. Filling kerosene-based magnetic liquid into the hollow ball and sealing it with a threaded plug can effectively reduce the volatilization of the magnetic liquid in the working environment, increase the stability of the magnetic liquid and the reliability of the damper.

[0067] 5. The ball can roll in any direction on the hemispherical groove surface, which can reduce the shaking of the structure in any direction in the horizontal plane and has the function of multi-directional vibration reduction.

[0068] 6. The bottom of the damper housing adopts a structural design of a disc with three threaded holes, which is fixedly connected to the vibration structure by bolts, so that the damper has better stability during work.

[0069] Anything not described in the present invention is applicable to the prior art.

Claims

1. A tuned magnetic liquid rolling ball damper, characterized in that The damper comprises a cylindrical container with a hemispherical groove, a cylindrical solenoid coil, a horizontal base, a hollow rolling ball and a kerosene-based magnetic liquid; wherein the cylindrical solenoid coil is evenly wound on the wall surface of the cylindrical container body shell, the cylindrical container is located on the horizontal base, the hollow rolling ball has a kerosene-based magnetic liquid inside; the hollow rolling ball is in the hemispherical groove in the cylindrical container; The upper part of the cylindrical container is an open hemispherical groove, the top of the groove is a protruding upper edge of the shell, and the bottom of the cylindrical container is a protruding horizontal base; The hollow rolling ball is a hollow sphere; the top of the shell has a screw hole equipped with a threaded plug; The radius of the hollow rolling ball is 1 / 12 to 1 / 8 of the radius of the groove; The cylindrical solenoid coil is a copper core enameled wire, which is wound with 4 to 7 layers in total and has a rated current of 5A. The kerosene-based magnetic liquid is a kerosene-based Fe3O4 magnetic liquid with a density of 1.36 g / cm 3 ; The ferroferric oxide is a nanoparticle with a diameter ranging from 2 to 20 nm; the volume of the kerosene-based magnetic liquid is 1 / 4 to 3 / 4 of the volume inside the spherical shell; The diameter of the cylindrical main body shell ranges from 0.65m to 1.45m, and the radius of the internal hemispherical groove ranges from 0.3m to 0.7m; The shell thickness of the hollow ball is 8-12 mm, and the material is resin material.

2. The tuned magnetic liquid rolling ball damper as described in claim 1 is characterized in that the horizontal base has fixing screw holes evenly distributed along the circumference.

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