CN114321552B

CN114321552B - Magnetorheological energy accumulator for water hammer protection and installation method and control system thereof

Info

Publication number: CN114321552B
Application number: CN202210003563.0A
Authority: CN
Inventors: 王强; 吴猛猛; 杨家轩; 张亚东; 黄宜超
Original assignee: Ocean University of China
Current assignee: Ocean University of China
Priority date: 2022-01-04
Filing date: 2022-01-04
Publication date: 2023-02-10
Anticipated expiration: 2042-01-04
Also published as: CN114321552A

Abstract

A magnetorheological energy accumulator for water hammer protection and an installation method and a control system thereof are disclosed, wherein the magnetorheological energy accumulator comprises a shell with a sealing cavity, and a piston body and a magnetorheological mechanism are arranged in the sealing cavity; the piston body comprises a first piston, a second piston and a connecting part, the peripheries of the first piston and the second piston are matched with the inner wall of the shell, and the connecting part is arranged between the first piston and the second piston; the magnetorheological mechanism is arranged between the connecting part and the inner wall of the shell; the outer sides of two ends of the piston body are respectively provided with a resetting mechanism and a through flow hole, and the through flow hole is formed in the shell; when the water hammer impact occurs on the conveying pipeline, the fluid pushes the piston body to move towards the side of the resetting mechanism through the through-flow hole, and the magnetorheological mechanism generates damping force to control the water hammer impact; when the water hammer impacts, the piston body moves to the side of the through-flow hole to reset under the pushing of the resetting mechanism. The magnetorheological energy accumulator is a semi-active control device; the equipment body and assembly occupy small space, compact structure and reasonable design.

Description

Magnetorheological energy accumulator for water hammer protection and installation method and control system thereof

Technical Field

The invention belongs to the technical field of fluid conveying, relates to structure and performance improvement of a water hammer protection energy accumulator, and particularly relates to a magnetorheological energy accumulator for water hammer protection, an installation method and a control system thereof.

Background

The pipeline is used as a fluid conveying carrier and is widely applied to the fields of petrochemical industry, aerospace, nuclear industry, hydraulic engineering, agricultural irrigation and the like. The vibration of the pipeline is easy to damage the pipeline system, and threatens the safe operation and stability of the pipeline system; meanwhile, large-decibel noise is generated, the working environment is deteriorated, and a large factor causing pipeline vibration is the water hammer.

The water hammer is a transient process in which the motion parameters of fluid change rapidly along with space and time, the generated impact pressure can reach several times or even dozens of times of the normal fluid conveying pressure, and the induced fluid pulse can induce the vibration of the pipe wall. As shown in fig. 1 and 2, the water hammer effect is a phenomenon that fluid flow in a pipeline is suddenly changed due to factors such as rapid opening and closing of a valve, starting and stopping of a pump and the like, so that fluid pressure is rapidly increased or decreased alternately, strong impact is generated on the pipeline, a valve, the pump and the like, and noise is generated due to pipeline vibration. It is essentially the inertia and compressibility of a liquid, and changes in momentum cause changes in force as the flow velocity changes in the tube.

Accumulators are often used in piping systems to dampen and eliminate water hammer in response to excessive vibration and noise caused by pulsation or shock of fluid pressure. The energy accumulator is used for storing energy, eliminating impact and reducing vibration. The existing traditional energy accumulator can be divided into a weight type energy accumulator, a spring type energy accumulator and a gas type energy accumulator according to the structural form, the weight type energy accumulator has a simple structure, but is limited in installation and poor in sensitivity; the spring type energy accumulator has simple structure and low cost, is not sensitive to pressure and is only suitable for a small-capacity low-pressure system; the gas accumulator seals the inflated bladder in the pressure tank, and has the advantages of small inertia, sensitive reaction, oil-gas separation, simple structure, convenient installation and maintenance and wide application.

In practical use, however, the existing conventional energy accumulator still has the following three defects:

firstly, most energy storage ware protection belongs to passive form protection, and compressed gas or elastomer cushion the power consumption at water hammer impact in-process, can only rely on the parameter setting passive operation in advance, can't make the adjustment according to the operating mode, do not possess the real time control ability.

Secondly, the structure of the energy accumulator is complex and the size is large, and the occupied space is too much. The energy accumulator is installed along the radial direction of the pipeline in an installation mode, as shown in the attached figure 3, a very large radial space is needed, and the requirements of special application fields such as ships and warships with limited space cannot be met.

Thirdly, under the working condition that the fluid pressure in the pipeline is adjusted, the existing energy accumulator can be compressed excessively in advance, the acting distance and the buffering effect of the energy accumulator under the impact of a subsequent water hammer are reduced, and static pressure loss also exists.

Disclosure of Invention

The invention aims to provide a magnetorheological energy accumulator for water hammer protection, an installation method and a control system thereof, which are used for solving the problems that the existing energy accumulator cannot be regulated and controlled in real time and occupies a large space.

In order to realize the purpose of the invention, the following technical scheme is adopted:

the magnetorheological energy accumulator comprises a shell with a sealing cavity, and a piston body and a magnetorheological mechanism are arranged in the sealing cavity; the piston body comprises a first piston, a second piston and a connecting part, the peripheries of the first piston and the second piston are matched with the inner wall of the shell, and the connecting part is arranged between the first piston and the second piston; the magnetorheological mechanism is arranged between the connecting part and the inner wall of the shell; the outer sides of two ends of the piston body are provided with a resetting mechanism and a through flow hole, and the through flow hole is formed in the shell; when the water hammer impact occurs on the conveying pipeline, the fluid pushes the piston body to move towards the side of the resetting mechanism through the through-flow hole, and the magnetorheological mechanism generates damping force to control the water hammer impact; when the water hammer impacts, the piston body moves to the side of the through-flow hole to reset under the pushing of the resetting mechanism.

In order to further realize the purpose of the invention, the following technical scheme can be adopted:

the magnetorheological energy accumulator for water hammer protection comprises a magnetic conductive sleeve, an excitation coil, a throttling channel and magnetorheological fluid, wherein the excitation coil is arranged in the magnetic conductive sleeve, the magnetic conductive sleeve is fixed on the inner wall of the shell, the excitation coil is driven by an external power supply to work, the throttling channel through which the magnetorheological fluid flows is arranged between the magnetic conductive sleeve and the connecting part, and the magnetorheological fluid is filled in a cavity formed by the piston body and the inner wall of the shell.

The magnetorheological energy accumulator for water hammer protection comprises a shell, a shell and a cover, wherein the shell comprises an inner pipe and an outer pipe which are coaxial, one end of the outer pipe is hermetically connected with the inner pipe, and the other end of the outer pipe is hermetically connected with the inner pipe through an end cover; a sealed cavity is formed between the inner pipe and the outer pipe, and the through-flow hole is formed in the inner pipe.

According to the magnetorheological energy accumulator for water hammer protection, the first piston and the second piston in the sealing cavity are both annular bodies, and the connecting part is a cylindrical body sleeved on the periphery of the inner pipe.

According to the magnetorheological energy accumulator for water hammer protection, the magnetorheological mechanism in the sealing cavity is an annular body.

The magnetorheological energy accumulator for water hammer protection is characterized in that a limiting stopper is arranged on the inner wall of the shell between the through hole and the piston body.

The magnetorheological energy accumulator for water hammer protection is characterized in that the connecting part is hermetically connected with the first piston and/or the second piston through a thread structure; the first piston and the second piston are matched with the inner wall of the shell through dynamic seals.

According to the magnetorheological energy accumulator for water hammer protection, the resetting mechanism is a gas compensation chamber arranged between the end part of the piston body and the shell, and compressed inert gas is filled in the gas compensation chamber.

The invention provides a method for installing a magnetorheological energy accumulator for water hammer protection, wherein the magnetorheological energy accumulator is arranged along the trend of a conveying pipeline; when the shell is of a double-side-wall structure consisting of an inner pipe and an outer pipe, two ends of the inner pipe are directly connected with the conveying pipeline through a threaded structure or a flange, or the inner pipe is arranged on the periphery of the conveying pipeline and hermetically communicates the through hole with a through hole formed in the conveying pipeline; when the shell is of a single-side-wall structure, the through hole is formed in the conveying pipeline, and the through hole in the shell is opposite to the through hole in position and is communicated with the through hole in a sealing mode.

The invention provides a magnetorheological energy accumulator control system for water hammer protection, which comprises a pressure sensor, a signal conditioning circuit, an A/D (analog/digital) conversion circuit, a real-time control system, a D/A conversion circuit and a current driver, wherein the pressure sensor is connected with the signal conditioning circuit; the real-time control system comprises an input and response state analysis unit, a system control unit and a buffer energy absorber controller which are sequentially in signal connection, wherein the signal output end of the pressure sensor, the signal conditioning circuit, the A/D conversion circuit and the signal input end of the input and response state analysis unit are sequentially in signal connection; the signal output end of the buffer energy absorber controller, the D/A conversion circuit and the input end of the current driver are sequentially in signal connection; the output end of the current driver is electrically connected with the magnetorheological mechanism of any one of the magnetorheological energy accumulators; and converting a water hammer pressure signal acquired by the pressure sensor into a driving current signal of the magnetorheological mechanism, so that the magnetorheological energy accumulator generates a damping force to control the impact of the water hammer.

Compared with the prior art, the invention has the advantages that:

1. the magneto-rheological energy accumulator is a semi-active control device, has real-time accurate controllable output effect, has controllable damping force controlled by an external magnetic field, and has the advantages that the output damping force is continuously adjustable compared with a passive energy accumulator structure, and the damping force of the magneto-rheological energy accumulator can be continuously, accurately and controllable in a large range by virtue of the magneto-rheological effect.

2. The invention has small occupied space, compact structure and reasonable design; the processing and manufacturing are easy, the number of parts is small, and the manufacturing cost is low; the original pipeline does not need to be replaced, the pipeline outer pipe is mounted and attached to the outer pipe of the pipeline along the moving direction or the axial direction of the conveying pipeline, the occupied space is small, and especially the occupied space in the radial direction of the pipeline can be greatly reduced.

3. Under the working condition of adjusting the fluid pressure, particularly when the fluid pressure in the initial state is greater than the zero-current initial state pressure of the energy accumulator, the magnetorheological energy accumulator can provide locking force for the whole piston to eliminate static pressure loss by applying locking current.

4. The invention has high reliability, and the mechanisms such as the gas compensation chamber, the piston body, the magneto-rheological mechanism and the like are a passive energy accumulator, so that the normal operation of the whole system can be ensured when special conditions such as power failure or control failure occur, and the system failure can not be directly caused.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below.

FIG. 1 is a schematic view of a piping system in a normal fluid delivery state;

FIG. 2 is a schematic diagram of a state of a pipeline system in which a water hammer effect occurs;

FIG. 3 is a schematic view of a prior art radial mounting of a conventional accumulator;

FIG. 4 is a schematic structural view of the present invention;

FIG. 5 is a schematic magnetic circuit diagram of the exciter coil of FIG. 4;

FIG. 6 is an enlarged view of portion I of FIG. 5;

FIG. 7 is a schematic view of the MR accumulator of FIG. 4 in an initial state;

FIG. 8 is a schematic view of an intermediate state of the magnetorheological accumulator of FIG. 4;

FIG. 9 is a schematic view of the end state of the magnetorheological accumulator of FIG. 4;

FIG. 10 is a perspective view of the piston body of FIG. 4;

FIG. 11 is a cross-sectional view of the piston body illustrated in FIG. 10;

FIG. 12 is a schematic view of an arrangement of the magnetorheological accumulator and the delivery pipe of the present invention;

FIG. 13 is a schematic view of another embodiment of the magnetorheological accumulator and the delivery pipe according to the present invention;

FIG. 14 is a perspective view of the delivery conduit of FIG. 13;

FIG. 15 is an electrical schematic of the magnetorheological accumulator control system of the present invention.

Reference numerals: 1-a thread pair; 2-inner tube; 3-an outer tube; 4-piston external dynamic sealing; 5-left chamber; 6-a piston body; 7-a field coil; 8-a magnetic conductive sleeve; 9-a right chamber; 10-piston capping; 11-a limit check ring; 12-an end cap; 13-inner static sealing; 14-a locking bolt; 15-locking the nut; 16-outer static seal; 17-a through-flow aperture; 18-a throttling channel; 19-piston internal dynamic sealing; 20-a gas compensation chamber; 21-magnetic induction lines; 22-magnetorheological fluid; 23-compressed gas; 30-a conventional accumulator; 31-a delivery conduit; 32-a magnetorheological accumulator; 33-through holes.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention.

As shown in fig. 1 to 14, in the magnetorheological energy accumulator for water hammer protection disclosed in this embodiment, the magnetorheological energy accumulator 32 structurally comprises a housing, a piston body 6, a magnetorheological mechanism and the like, the housing has a sealing cavity, and the piston body 6 and the magnetorheological mechanism are disposed in the sealing cavity.

The shell is made of non-magnetic light materials, and the piston body 6 and the magnetic sleeve 8 in the magneto-rheological mechanism are made of magnetic materials.

As shown in fig. 4 and 5, the housing of the present embodiment has a cylindrical structure formed by the inner tube 2 and the outer tube 3 which are coaxial. The inner pipe 2 is long, two ends of the inner pipe are used for being matched with the conveying pipeline 31, and the outer pipe 3 is arranged in the middle of the inner pipe 2. One end of the outer tube 3 is hermetically connected with the inner tube 2, and the other end of the outer tube 3 is hermetically connected with the inner tube 2 through an end cover 12; a sealed cavity is formed between the inner pipe 2 and the outer pipe 3, and the inner pipe 2 is provided with a through hole 17 communicated with the conveying pipeline 31.

Taking the direction shown in fig. 4 as an example, the left end of the outer tube 3 is connected with the inner tube 2 in a sealing manner on site by welding, the right end of the outer tube 3 is open, the end cover 12 is of a detachable structure, and the inner static seal 13 and the outer static seal 16 are respectively matched with the outer wall of the inner tube 2 and the inner wall of the outer tube 3 to form sealing connection. Meanwhile, the outer tube 3 is provided with a fixing lug or a flange with a bolt hole, and the end cover 12 and the outer tube 3 are fixed by a locking bolt 14 and a locking nut 15. In this way, the space surrounded by the outer tube 3, the inner tube 2, and the end cap 12 serves as a sealed chamber of the housing.

The housing formed by the inner tube 2 and the outer tube 3 has a cylindrical double-wall structure, i.e., the inner tube 2 is an inner wall and the outer tube 3 is an outer wall. Besides the structure shown in fig. 4 of this embodiment, the housing may also be a single-side-wall structure, for example, the housing is directly made of a single tube, one end of the single tube is sealed, the other end of the single tube is provided with an end cap 12, and a sealed cavity is formed by the space enclosed by the inner cavity of the single tube and the end cap 12.

As shown in fig. 4, 10 and 11, the piston body 6 of the present embodiment is composed of a first piston, a second piston and a connecting portion, the outer peripheries of the first piston and the second piston are matched with the inner wall of the housing through a piston outer dynamic seal 4 and a piston inner dynamic seal 19, and the connecting portion is arranged between the first piston and the second piston. And the first piston and the second piston are both annular bodies, and the connecting part is a cylindrical body sleeved on the periphery of the inner pipe 2.

Taking the direction shown in fig. 4 as an example, the left end of the piston body 6 is a first piston, and the right end thereof is a second piston. In order to improve the connection strength of the piston body 6 and to simplify the manufacturing steps, the first piston is manufactured integrally with the connecting portion. At this time, the second piston is the piston cap 10, and then is tightly coupled as a whole by the screw pair 1 between the end of the coupling portion and the piston cap 10.

As shown in fig. 4-6, the magnetorheological mechanism of the present embodiment is disposed between the connecting portion and the inner wall of the housing, and a reset mechanism and a through hole 17 are respectively disposed at the outer sides of the two ends of the piston body 6 in the housing.

The magneto-rheological mechanism comprises a magnetic sleeve 8, an excitation coil 7, a throttling channel 18 and magneto-rheological fluid 22. The magnet exciting coil 7 is arranged in the magnetic conductive sleeve 8, the magnetic conductive sleeve 8 is fixed on the inner wall of the shell, the magnet exciting coil 7 is driven by an external power supply to work, a throttling channel 18 through which magnetorheological fluid 22 flows is arranged between the magnetic conductive sleeve 8 and the connecting part, the inner tube 2, the outer tube 3 and the piston body 6 are sealed to form a left cavity 5 and a right cavity 9 of the magnetorheological fluid 22, and the magnetorheological fluid 22 is filled in a cavity formed by the piston body 6 and the inner wall of the shell.

Through the magnetorheological mechanism, when the fluid in the conveying pipeline 31 generates water hammer impact, the fluid enters the sealing cavity through the through hole 17 to push the piston body 6 to move towards the reset mechanism side, and the magnetorheological mechanism generates damping force to control the water hammer impact; when the water hammer impact is finished, the piston body 6 moves and resets towards the through-flow hole 17 under the pushing of the resetting mechanism.

The magnetorheological fluid 22 is an intelligent material, is a special suspension system formed by uniformly dispersing micron-sized magnetizable particles in specific carrier mother liquor and additives, and has the advantages of reversibility, controllability, quick response, low energy consumption and the like. The magnetorheological effect means that when a magnetic field is applied from the outside, the viscosity, the shear yield stress and the like of the magnetorheological fluid 22 are changed, the magnetic particles in the magnetorheological fluid 22 are regularly arranged from disorder along with the increase of the magnetic field intensity, and then are closely arranged in a chain bundle shape to be in a semi-solid state, the reaction time is in a millisecond range, and the process is reversible.

The magnetorheological fluid 22 is the same as a newtonian fluid when no magnetic field is applied. At this time, the magnetic particles in the magnetorheological fluid 22 are distributed in the base fluid in a disordered manner. When a magnetic field is applied between the upper and lower pole plates, the magnetic particles begin to be regularly arranged along the magnetic field direction, and at this time, the shear yield strength of the magnetorheological fluid 22 begins to increase. As the magnetic field continues to increase, the magnetic particles form a tight chain bundle arrangement along the direction of the magnetic field, and the magnetorheological fluid 22 is in a semi-solid state and requires a larger shear force to flow.

When the energized coil is used to provide a magnetic field for the magnetorheological energy accumulator 32, the shear strength of the magnetorheological fluid 22 in the magnetorheological energy accumulator 32 will change regularly with the change of the magnitude of the externally applied current, so that semi-active control can be realized. The semi-active control process depends on structural reaction and external excitation information, and the structural reaction is reduced by changing the parameters of rigidity or damping of the structure in real time through a small amount of energy. Semi-active control does not require input of a large amount of external energy to directly provide control force, and only an actuator for implementing the control force needs to be adjusted by a small amount of energy, so that the actuator actively utilizes reciprocating relative deformation or speed of structural vibration to realize active optimal control force as far as possible. Therefore, the magnetorheological energy accumulator 32 manufactured by the magnetorheological effect of the magnetorheological fluid 22 is a semi-actively controlled energy accumulator and has good performance in the aspects of impact, vibration and the like, so that the problem of water hammer of a pipeline system can be effectively solved.

When the magneto-rheological mechanism is installed, the magnetic conductive sleeve 8 and the inner wall of the outer tube 3 are fixed in an interference fit mode, and the excitation coil 7 is wound inside the magnetic conductive sleeve 8 and fixed in a sizing mode through sealant.

When the magnetorheological mechanism works, the magnet exciting coil 7 is powered by an external power supply to generate a magnetic induction line 21, vertically penetrates through the throttling channel 18 along the magnetic sleeve 8, and then enters the piston body 6 to form a closed loop, so that the direction of a magnetic field is ensured to be vertical to the movement direction of the magnetorheological fluid 22 in the throttling channel 18.

One end of the piston body 6 and the shell form a reset mechanism, the reset mechanism of the embodiment is a gas compensation chamber 20, and the gas compensation chamber 20 is filled with compressed gas 23. In addition, the resetting mechanism can also be replaced by a linear spring or a butterfly spring and the like, and has the same compression and resetting effects.

With continued reference to fig. 4, in this embodiment, four evenly distributed through-flow holes 17 are formed in the inner tube 2 for guiding the fluid in the delivery pipe 31 to enter the housing and impact the right end face of the piston cover 10, and the piston is limited by the limit check ring 11 on the left side of the through-flow holes 17. The limit retainer ring 11 here is a limit stop and functions to limit the distance of the piston body 6 moving rightward. The limiting block can adopt a convex block besides a check ring structure, or directly utilize a magnetic sleeve 8 fixed on the inner wall of the outer tube 3 for limiting.

As shown in fig. 12, the magnetorheological accumulator 32 of the present embodiment is connected to the controlled pipe system by a thread pair 1. At this time, regarding the newly-built pipeline system, the installation mode is that after the two ends of the magnetorheological energy accumulator 32 and the conveying pipeline 31 are connected to form a whole, the pipeline is laid and installed; in the case of a pipe system retrofit, the installation is to cut and remove a pipe a distance away from the delivery pipe 31 and then install the magnetorheological accumulator 32 directly at the cutting site.

Under the above-mentioned mounting structure, the through-flow hole 17 directly communicates with the conveying pipeline 3, and the action process of piston body 6 and magnetorheological fluid 22 is as follows:

as shown in fig. 7, when no water hammer impact occurs, the gas pressure of the compressed gas 23 in the gas compensation chamber 20 in the magnetorheological energy accumulator 32 and the locking force generated by applying the locking current combine to ensure that the initial position of the piston body 6 is stopped at the position of the limit check ring 11; when the pipeline has water hammer impact, the fluid of the conveying pipeline 31 enters the shell sealing cavity through the through hole 17 to impact the outer end face of the piston cover 10, and the piston body 6 of the energy accumulator is pushed to move relatively between the inner pipe 2 and the outer pipe 3 of the shell.

As shown in fig. 8, the piston body 6 is pushed by the fluid under the impact of the water hammer to move to the left, so as to force the magnetorheological fluid 22 to move from the right to the left, and in the process, the magnitude of the current of the excitation coil 7 is adjusted according to the impact condition of the water hammer, so that the magnetic field strength is changed, the shear yield strength of the magnetorheological fluid 22 is adjusted, the required damping force is generated, and the water hammer impact is controlled.

As shown in fig. 9, the compressed gas 23 in the gas compensation chamber 20 continues to be compressed until it reaches an end position. When the water hammer impact process is over, the piston as a whole is reset to the position shown in fig. 7 under the pressure of the compressed gas 23.

The gas compensation chamber 20 and the compressed gas 23 have the functions of restoring the piston, namely, when a water hammer impact control process is finished, the piston body 6 is restored to the position of the limit retainer ring 11 by the pressure of the compressed gas 23; on the other hand, under the condition that the magnetorheological fluid 22 does not leak, the gas compensation chamber 20 and the internal compressed gas 23 are passive energy accumulators, and when special conditions such as power failure or control failure occur, the magnetorheological energy accumulator 32 still can realize a part of water hammer buffering function, and can also ensure the normal operation of the whole system, so that the system cannot be directly failed, and the reliability is higher.

The inner tube 2 and the outer tube 3 of the shell are designed into an integrated structure, so that the number of parts of the magnetorheological energy accumulator 32 can be reduced to the maximum extent, the compact and stable structure of the magnetorheological energy accumulator is ensured, the connection surfaces needing to be sealed are reduced, and the possible leakage hidden danger of the magnetorheological fluid 22 is reduced.

The end cover 12 is tightly matched with the inner pipe 2 and the outer pipe 3 by the pressing force provided by the locking bolt 14 and the locking nut 15, and the inner static seal 13 and the outer static seal 16 are adopted for sealing, so that the fluid is prevented from leaking; the sliding seal connection is realized through O-shaped ring dynamic seal between the inner side and the outer side of the piston body 6 and the outer wall of the inner tube 2 and the inner wall of the outer tube 3, the leakage of the magnetorheological fluid 22 and the gas in the gas compensation chamber 20 is prevented, meanwhile, the sliding seal is realized through the O-shaped ring between the inner side and the outer side of the piston sealing cover 10 and the inner wall of the outer tube 3 in the shell, and the leakage of the magnetorheological fluid 22 and the fluid permeating into the right chamber 9 is prevented.

As shown in fig. 4 and 5, a gap between the ring surface of the magnetic conductive sleeve 8 and the magnet exciting coil 7 after being sealed and the piston body 6 forms a throttling channel 18 of the magnetorheological fluid 22, and the right chamber 9, the left chamber 5 and the throttling channel 18 are filled with the magnetorheological fluid 22. The piston body 6 moves to enable the magnetorheological fluid 22 to flow in an exchange manner in the right cavity 9 and the left cavity 5 through the throttling channel 18, and the magnetorheological effect is achieved under the action of an external magnetic field.

The method for installing the magnetorheological accumulator disclosed by the embodiment is to arrange the magnetorheological accumulator along the trend or the axial direction of the conveying pipeline 31. The configuration of the MR accumulator 32 is as described above and will not be described in detail herein.

When the shell is of a double-side-wall structure consisting of the inner pipe 2 and the outer pipe 3, two ends of the inner pipe 2 are directly connected with the conveying pipeline 31 through a thread structure or a flange, or the inner pipe 2 is arranged on the periphery of the conveying pipeline 31 and hermetically communicates the through holes 17 with through holes 33 formed in the conveying pipeline 31. At this time, there are two installation connection modes of the magnetorheological accumulator 32 and the pipeline system:

first, the inner pipe 2 is connected with the conveying pipeline 31 through the screw pair 1 at the left and right ends, as shown in fig. 12.

Secondly, the inner pipe 2 and the conveying pipeline 31 are assembled in an interference fit mode, as shown in fig. 14. During assembly, four through holes 33 are uniformly distributed on the conveying pipeline 31 at the installation part, as shown in fig. 13; the through-hole 33 is then aligned with the through-flow hole 17 of the inner tube 2 and the possible gap is sealed, completing the installation.

When the shell is of a single-side-wall structure, a through hole 33 is formed in the conveying pipeline 31, as shown in fig. 14, and then the through hole 17 in the shell is opposite to the through hole 33 and is in sealed communication with the through hole, and the shell is fixed through a bracket or a buckle and the like. The magnetorheological energy accumulator 32 and the housing are also arranged along the direction of the conveying pipe 31 or axially, and the whole is positioned on the side of the conveying pipe 31, so that the occupied space is increased. The radial space usage can still be significantly reduced relative to conventional accumulators 30.

The structure of the magnetorheological energy accumulator 32 adopted in the magnetorheological energy accumulator control system disclosed in the embodiment is as described above, and is not described herein again.

As shown in fig. 15, the control system includes a pressure sensor, a signal conditioning circuit, an a/D conversion circuit, a real-time control system, a D/a conversion circuit, and a current driver. A plurality of pressure sensors are arranged in the water incoming direction of the electro-hydraulic ball valve, namely the direction in which the water hammer impacts, so that the information such as the size and the form of the water hammer effect can be accurately captured; the signals obtained by the pressure sensor are input into the real-time control system through the conditioning circuit and the A/D conversion circuit; the output force of the magnetorheological accumulator 32 is obtained through the input and response state analysis unit and the system control unit; signals of the buffer energy absorber controller are input into a magneto-rheological mechanism of the magneto-rheological energy accumulator 32 through a D/A conversion circuit and a current driver to provide a driving power supply for the excitation coil 7; the pressure sensing of the water hammer impact and the damping force and action provided by the magnetorheological accumulator 32 form a control closed loop.

The invention is a controllable novel energy accumulator which can change the state and parameters on line, has important significance for improving the stability of the pipeline during working, expanding the water hammer protection method and reducing vibration and noise, and can effectively expand the application of intelligent materials and vibration semi-active control technology in the field of energy accumulators.

The technical contents not described in detail in the invention are all known technologies.

Claims

1. The magnetorheological energy accumulator comprises a shell with a sealing cavity, and is characterized in that a piston body and a magnetorheological mechanism are arranged in the sealing cavity; the piston body comprises a first piston, a second piston and a connecting part, the peripheries of the first piston and the second piston are matched with the inner wall of the shell, and the connecting part is arranged between the first piston and the second piston; the magnetorheological mechanism is arranged between the connecting part and the inner wall of the shell; the outer sides of two ends of the piston body are respectively provided with a resetting mechanism and a through flow hole, and the through flow hole is formed in the shell; when the water hammer impact occurs on the conveying pipeline, the fluid pushes the piston body to move towards the side of the resetting mechanism through the through-flow hole, and the magnetorheological mechanism generates damping force to control the water hammer impact; when the impact of the water hammer is finished, the piston body moves to the through-flow hole side to reset under the pushing of the resetting mechanism; the magneto-rheological mechanism comprises a magnetic conductive sleeve, an excitation coil, a throttling channel and magneto-rheological fluid, wherein the excitation coil is arranged in the magnetic conductive sleeve, the magnetic conductive sleeve is fixed on the inner wall of the shell, the excitation coil is driven by an external power supply to work, the throttling channel through which the magneto-rheological fluid flows is arranged between the magnetic conductive sleeve and the connecting part, and the magneto-rheological fluid is filled in a cavity formed by the piston body and the inner wall of the shell.

2. The magnetorheological accumulator for water hammer protection according to claim 1, wherein the housing comprises an inner tube and an outer tube which are coaxial, one end of the outer tube is connected with the inner tube in a sealing manner, and the other end of the outer tube is connected with the inner tube in a sealing manner through an end cover; a sealed cavity is formed between the inner pipe and the outer pipe, and the through-flow hole is formed in the inner pipe.

3. The magnetorheological energy accumulator for water hammer protection according to claim 2, wherein the first piston and the second piston in the sealing cavity are both annular bodies, and the connecting part is a cylindrical body sleeved on the outer periphery of the inner pipe.

4. The magnetorheological accumulator for water hammer protection of claim 2, wherein the magnetorheological mechanism in the seal cavity is an annular body.

5. The magnetorheological accumulator for water hammer protection according to claim 1, wherein a limit stop is arranged on the inner wall of the shell between the through-flow hole and the piston body.

6. The magnetorheological accumulator for water hammer protection according to claim 1, wherein the connection part and the first piston and/or the second piston are in sealing connection through a thread structure; the first piston and the second piston are matched with the inner wall of the shell through dynamic seals.

7. The magnetorheological accumulator for water hammer protection according to claim 1, wherein the return mechanism is a gas compensation chamber provided between the end of the piston body and the housing, the gas compensation chamber being filled with a compressed inert gas.

8. A method for mounting a magnetorheological accumulator for water hammer protection, wherein the magnetorheological accumulator of any one of claims 1 to 7 is arranged along the direction of a conveying pipeline; when the shell is of a double-side-wall structure consisting of an inner pipe and an outer pipe, two ends of the inner pipe are directly connected with the conveying pipeline through a threaded structure or a flange, or the inner pipe is arranged on the periphery of the conveying pipeline and hermetically communicates the through hole with a through hole formed in the conveying pipeline; when the shell is of a single-side-wall structure, the through hole is formed in the conveying pipeline, and the through hole in the shell is opposite to the through hole in position and is communicated with the through hole in a sealing mode.

9. The magnetorheological energy accumulator control system for water hammer protection is characterized by comprising a pressure sensor, a signal conditioning circuit, an A/D conversion circuit, a real-time control system, a D/A conversion circuit and a current driver; the real-time control system comprises an input and response state analysis unit, a system control unit and a buffer energy absorber controller which are sequentially in signal connection, wherein the signal output end of the pressure sensor, the signal conditioning circuit, the A/D conversion circuit and the signal input end of the input and response state analysis unit are sequentially in signal connection; the signal output end of the buffer energy absorber controller, the D/A conversion circuit and the input end of the current driver are sequentially in signal connection; the output end of the current driver is electrically connected with the magneto-rheological mechanism of the magneto-rheological energy accumulator of any one of claims 1 to 7; and converting a water hammer pressure signal acquired by the pressure sensor into a driving current signal of the magnetorheological mechanism, so that the magnetorheological energy accumulator generates damping force to control the impact of the water hammer.