DE102018207216A1 - Device for damping pressure fluctuations - Google Patents

Abstract

A device for damping pressure fluctuations (10) is described which comprises a main flow channel (1) and at least one secondary flow channel (2), wherein the secondary flow channel (2) comprises a first end (3) and a second end (4) the first end (3) via a branch (6) with the main flow channel (1) is fluidically connected and the second end (4) by means of a closure device (5) is closable.

Description

The present invention relates to an apparatus and a method for damping pressure fluctuations, in particular in connection with pumping devices and hydraulic systems. The invention also relates to a pumping device and a hydraulic device.

Pumping devices, particularly piston pumps or centrifugal pumps, are used to transport a working fluid, such as a gas or a liquid, particularly water or oil, from a low pressure side to a high pressure side of a hydraulic system connected to the pumping device. Pumping devices inherently cause hydraulic pressure fluctuations, particularly pressure waves or pressure pulsations. This is due to the operation of pumping devices and the associated effects, such as volume displacement and discontinuities within the pump during and between pumping events. Hydraulic pressure pulsations, depending on their amplitude and frequency, can cause severe damage and NVH problems in hydraulic systems connected to the pumping device. NVH stands for Noise Vibration Harshness, ie noise, vibration, roughness or for audible or perceptible vibrations in motor vehicles or on machines.

The difficulties mentioned can be caused either by high oscillation amplitudes or by small or medium oscillation amplitudes or occurring resonances with the flow channel, for example as a function of its dimensions and fastening. Typical examples in the automotive industry are broken line components of the fuel supply or loud noises caused by excessive vibrations of the fuel line, which are triggered by pressure fluctuations caused by the fuel pump. For some applications, even a small amplitude of pressure fluctuations is devastating, for example in the papermaking industry, where small pressure fluctuations can cause an irregular distribution of paper thickness.

To reduce pressure fluctuations to an acceptable level, it is attempted to design pumps to compensate for volume displacements or minimize discontinuities. In this context, pressure dampers have already been arranged inside pumps in order to dampen pressure fluctuations directly.

The previously known solutions are characterized by high complexity and high cost intensity. For example, in the document DE 10 2015 000 418 A1 a damping device, in particular for damping or avoiding pressure surges, such as pulsations, disclosed in hydraulic supply circuits. In this case, a damping tube is provided, which has at least one pipe wall extending through, leading to a Helmholtz volume within the damping housing branch opening to form a Helmholtz resonator in an area located within its length. In addition, a fluid filter is provided.

In addition, pumping devices which do not include damper-integrated damping means are also subject to pressure pulsations which particularly affect the connected piping system. There is therefore an interest in solutions that provide reliable and effective protection of systems connected to a pump, such as piping or other components or subsystems, from damage due to pressure fluctuations and reduce NVH problems.

Against this background, it is the object of the present invention to provide a device for damping pressure fluctuations, as well as a pump device, a hydraulic device and a motor vehicle, which reduce pressure fluctuations, in particular pressure surges or pulsations, effectively and inexpensively.

These objects are achieved by a device for damping pressure fluctuations according to claim 1, a pumping device according to claim 12, a hydraulic device according to claim 14, a method according to claim 15 and a motor vehicle according to claim 16. The dependent claims contain further advantageous embodiments of the invention.

The device according to the invention for damping pressure fluctuations, in particular for damping pressure waves, pressure surges or pressure pulsations, comprises a main flow channel and at least one secondary flow channel. The bypass duct includes a first end and a second end. The first end is fluidly connected via a branch to the main flow channel. The second end can be closed by means of a closure device.

Preferably, the device comprises a closure device for closing the second end. The closure device can be designed, for example, as a stopper, stopper or cap.

The device according to the invention has the advantage that pressure fluctuations are damped very effectively by the secondary flow channel. The secondary flow channel causes pressure waves to be absorbed and reflected. In addition, air flow can be trapped and retained as a damping medium in the secondary flow channel by its arrangement. The air in the system can be collected by the Venturi effect in the bypass duct. The concrete arrangement of the device has fluidic advantages and enhances the Venturi effect. Another advantage of the device is the utilization of gravity. This results in particular by the following principles of action and advantages: Pressure waves are collected and reflected. Air or other gases are absorbed as a damping medium by Venturi effect, in particular depending on the angle between the main and secondary flow channel. Air other gases will absorb as a damping medium by gravity, especially when the secondary flow channel is upwardly directed with respect to the main flow channel.

The advantages mentioned can be realized particularly simply by arranging the secondary flow channel so that it is arranged upwardly in relation to the main flow channel and / or a horizontal axis. The use of a main flow channel with at least one secondary flow channel has the further advantage that it represents a very simple and cost-effective solution that can also be easily and inexpensively integrated into existing systems.

The closeability of the second end of the bypass duct and the provision of a closure device have the advantage that in the bypass duct a closed fluid can be discharged in a simple manner. For example, if too much air or other gas is trapped in the bypass duct, it can be easily removed from the bypass duct via the closure means. As part of the application of the device, the second end of the bypass duct is preferably closed.

In an advantageous variant, the main flow channel in the region of the branch comprises a central axis. Furthermore, the secondary flow channel in the region of the branch comprises a central axis, wherein the central axis of the main flow channel and the center axis of the secondary flow channel forms an angle α between 10 degrees (10 degrees) and 170 degrees (170 degrees). The angle α can advantageously be measured starting from the central axis of the main flow channel in the propagation direction of the pressure fluctuations and / or in the flow direction of a fluid.

For example, the angle α between 20 degrees (20 degrees) and 80 degrees (80 degrees). This has the advantage that a fluid flowing through the main flow channel in the direction of propagation of the pressure waves is efficiently absorbed by the secondary flow channel and pressure waves are reflected back, ie back to the source of the pressure fluctuation, contrary to the flow direction and in the main flow channel.

In another variant, the angle α between 80 degrees (80 degrees) and 100 degrees (100 degrees). This variant combines the advantages of angles less than 80 degrees (80 degrees) and greater than 100 degrees (100 degrees), and can be very effective at damping pressure fluctuations due to trapped air in the bypass passage. This variant acts like a Helmholtz resonator.

In another variant, the angle is α between 100 degrees (100 degrees) and 160 degrees (160 degrees). This variant is usable for the reduction of the reflected waves due to an obstacle against the propagation direction. The choice of the angle α can thus be done depending on the requirements of the particular application and the particular effect desired.

The main flow channel may comprise a central axis. Additionally or alternatively, the secondary flow channel may include a central axis. The main flow channel and / or the secondary flow channel may have a circular cross-section in a section perpendicular to their respective central axis. Advantageously, the central axis runs parallel to the flow direction in the main flow channel or in the secondary flow channel. As an alternative to a circular cross section, other shapes are possible.

The main flow channel and / or the secondary flow channel may have stiff, in particular solid or non-deformable, material or consist of such a material. Additionally or alternatively, the main flow channel and / or the secondary flow channel may comprise deformable material, in particular flexible material, or consist of such a material. The choice of material or material combination and the choice of stiffness or deformability can be made depending on the specific application-deformable material has the advantage over rigid material that pressure fluctuations can be attenuated more than is possible with rigid material.

In one variant, the device comprises at least two bypass ducts. The use of multiple bypass ducts has the advantage that, on the one hand, a stronger damping can be achieved, but on the other hand, depending on the particular application, pressure waves can be absorbed and reflected in different ways. This will be explained in detail with reference to the embodiments. For example, at least two secondary flow passages may be arranged in the axial direction with respect to the central axis of the main flow passage, offset from each other, for example, one behind the other. Additionally or alternatively, at least two bypass ducts in the radial direction with respect to the central axis of the main flow channel offset from each other, so in relation to their radial direction side by side, be arranged.

In an advantageous embodiment, the device comprises a branch for at least two flow channels. In other words, the branch may comprise at least two outflow channel outlets. The outputs can be arranged offset axially and / or radially to each other with respect to the central axis of the main flow channel.

Preferably, at least one secondary flow passage is arranged with respect to the main flow passage so as to have a slope in the region of the branch. The central axis of the secondary flow channel may have an inclination with respect to a horizontal, in particular with respect to the central axis of the main flow channel in the flow direction and / or propagation direction of the sound waves. The central axis of the bypass duct in these cases therefore has a component in the vertical direction. For example, the main flow passage may have a portion oriented so that the center axis of the main flow passage is located in this region parallel to a horizontal. The central axis of the bypass duct, which is connected in this area with the main flow channel, has, starting from the central axis of the main flow channel upwards, so with the central axis of the main flow channel forms an angle α greater than 0 degrees (0 °) and less than 180 degrees (180 °). Such a configuration has the advantage that air located in the main flow channel is collected by the secondary flow channel, is enclosed in this and is available as a damping medium available.

The pumping device according to the invention comprises a previously described device according to the invention. It has the same properties and advantages as the device according to the invention described above.

The pumping device according to the invention may in particular comprise a piston pump and / or a centrifugal pump.

The hydraulic device according to the invention comprises an above-described device according to the invention for damping pressure fluctuations and / or a previously described pump device according to the invention. The hydraulic device according to the invention has the same features and advantages as the device according to the invention described above and the pump device according to the invention.

In the context of the method according to the invention for damping pressure fluctuations, a device according to the invention and / or a pump device according to the invention and / or a hydraulic device according to the invention for damping pressure fluctuations in at least one flow channel is used. The method has the advantages and features already mentioned in connection with the device according to the invention.

The motor vehicle according to the invention comprises an above-described device according to the invention for damping pressure fluctuations and / or a pump device according to the invention and / or a hydraulic device according to the invention. The motor vehicle is a passenger car, a truck or a motorcycle. The pumping device or the hydraulic device may comprise an oil pump or a fuel pump. The motor vehicle according to the invention basically has the same features and advantages as the devices according to the invention already described.

The present invention has the overall advantage that it provides a simple and cost-effective way to reduce pressure fluctuations efficiently, in particular pressure surges compared to previously known solutions. It also offers the possibility to retrofit existing hydraulic systems simply and inexpensively. Furthermore, it enables efficient reflection of pressure waves. There is also a very wide range of applications, in particular with regard to temperature, pressure, type of fluid, flow rate and frequency. In contrast to a Helmholtz resonator, the present solution is very efficient for a wide frequency range.

Another advantage is that the device according to the invention can be changed, adapted, upgraded and retrofitted in a flexible manner, and in particular also depending on pressure fluctuations that occur as a function of the particular application. This can be done in particular by adding additional branches are provided, which are connected, if necessary, with corresponding bypass ducts. The number and shape of the bypass channels used can be adjusted and changed by simply adding or removing them. Since the present invention comprises no moving mechanical components, it is particularly robust and is characterized by a long service life.

In addition to the above applications, the present invention may be applied to various hydraulic systems that include pumping devices for transferring a working fluid from a low pressure side to a high pressure side of the system. Other applications outside the automotive industry are the petrochemical industry, where pumping equipment is used in conjunction with oil drilling and pipelining of oil. Another application is the papermaking industry, where centrifugal pumps are used to convey papermaking stock.

• 1 zeigt schematisch eine erfindungsgemäße Vorrichtung zum Dämpfen von Druckschwankungen in einer Explosionsansicht.
• 2 zeigt schematisch die in der 1 gezeigte erfindungsgemäße Vorrichtung zusammengesetzt in einer Seitenansicht.
• 3 zeigt schematisch eine weitere Variante einer erfindungsgemäßen Vorrichtung.
• 4 zeigt schematisch eine andere Variante einer erfindungsgemäßen Vorrichtung.
• 5 zeigt schematisch die in der 4 gezeigte Variante in einer anderen Anwendung.
• 6 zeigt schematisch eine weitere Anwendungsmöglichkeit der in der 4 gezeigten Variante der erfindungsgemäßen Vorrichtung.
• 7 zeigt schematisch eine weitere Anwendungsmöglichkeit der in den 1 und 2 gezeigten Variante der erfindungsgemäßen Vorrichtung.
• 8 zeigt schematisch eine weitere Variante der erfindungsgemäßen Vorrichtung.
• 9 zeigt schematisch noch weitere Varianten der erfindungsgemäßen Vorrichtung.
• 10 zeigt schematisch eine weitere Variante der erfindungsgemäßen Vorrichtung in einer perspektivischen Ansicht.
• 11 zeigt schematisch eine erfindungsgemäße Pumpvorrichtung.
• 12 zeigt schematisch eine erfindungsgemäße Hydraulikvorrichtung.
• 13 zeigt schematisch ein erfindungsgemäßes Kraftfahrzeug.

The invention will be explained in more detail below with reference to embodiments with reference to the accompanying figures. Although the invention is further illustrated and described in detail by the preferred embodiments, the invention is not limited by the disclosed examples, and other variations can be derived therefrom by those skilled in the art without departing from the scope of the invention.

• 1 schematically shows an inventive device for damping pressure fluctuations in an exploded view.
• 2 schematically shows the in the 1 shown inventive device composed in a side view.
• 3 schematically shows a further variant of a device according to the invention.
• 4 schematically shows another variant of a device according to the invention.
• 5 schematically shows the in the 4 shown variant in another application.
• 6 schematically shows a further application of the in the 4 shown variant of the device according to the invention.
• 7 schematically shows a further application of the in the 1 and 2 shown variant of the device according to the invention.
• 8th schematically shows a further variant of the device according to the invention.
• 9 schematically shows other variants of the device according to the invention.
• 10 schematically shows a further variant of the device according to the invention in a perspective view.
• 11 schematically shows a pumping device according to the invention.
• 12 schematically shows a hydraulic device according to the invention.
• 13 schematically shows a motor vehicle according to the invention.

The 1 schematically shows an inventive device for damping pressure fluctuations 10 in an exploded view. In addition, in the 1 an excitation source 15 shown. This is not part of the device according to the invention 10 , At the excitation source 15 , which potentially causes pressure fluctuations, in particular pressure waves, may be, for example, a piston pump or a centrifugal pump. The propagation direction of sound waves in a fluid flowing through the device according to the invention, for example water, fuel or oil, is indicated by an arrow 12 characterized. The flow direction of the fluid can with the propagation direction 12 It does not have to be identical. Furthermore, gravity is indicated by an arrow 11 characterized.

The device according to the invention 10 includes a main flow channel 1 , The main flow channel 1 includes a central axis 14 , The device further comprises a bypass duct 2 , The secondary flow channel 2 includes a central axis 13 , Furthermore, the secondary flow channel comprises 2 a first end 3 and a second end 4 , The device according to the invention also comprises a branch 6 , The branch 6 is designed to be the main flow channel 1 with the bypass duct 2 fluidically connect. This includes the branch 6 in the variant shown, a first connection opening 7 for connecting the branch 6 with a first region of the main flow channel 1 , a second connection opening 8th for connecting to a second region of the main flow channel 1 and a third connection opening 9 for fluidic connection with the first end 3 of the bypass duct 2 , The branch 6 In the present case, it is designed such that the center axes of the first connection opening 7 and the second connection opening 8th are identical and identical to the central axis 14 of the main flow channel 1 are, if this with the branch 6 connected is. The center axis of the third connection opening 9 closes with the center axis of the connection openings 7 and 8th an angle α one. When the bypass duct 2 with the third connection opening 9 of branch 6 is connected, so the central axis closes 13 of the bypass duct 2 an angle α with the central axis 14 of the main flow channel 1 one.

The second end 4 of the bypass duct 2 is with a closure device 5 closable. The closure device is preferably part of the device according to the invention 10 , The closure device 5 can be configured for example as a plug, as a plug or cap.

The angle α may depend on the particular application and the type of excitation source 15 and their position with respect to the main flow channel 1 and in terms of the direction of propagation 12 and / or the flow direction of the fluid to be determined. In a preferred variant, the second end 4 of the bypass duct 2 upwards. In the variant shown, the central axis 14 of the main flow channel 1 arranged horizontally. The central axis 13 of the bypass duct 2 points in relation to the central axis 14 of the main flow channel 1 a slope or other increase, so it has a vertical component or is in relation to the direction 11 Earth's gravity at least partially upwards.

The 2 shows the in the 1 shown device according to the invention 10 in assembled condition in a side view. In the 2 is the operation of the device according to the invention 10 illustrated. By the excitation source 15 become pressure waves 20 in the main flow channel 1 brought in. The propagation direction of the pressure waves 20 in the main flow channel 1 is with the reference number 23 characterized. One in the main flow channel 1 spreading pressure wave 21 will be in the branch 6 partly in the secondary flow channel 2 directed. The propagation direction of the waves 22 in the bypass duct 2 is by an arrow 25 characterized. In the bypass duct 2 become the waves 22 reflected. This is by an arrow 24 characterized. The reflected waves are preparing in the main flow channel 1 in the direction 24 , ie opposite to the propagation direction 23 by the excitation source 15 in the main flow channel 1 introduced waves 21 out. In other words, the reflected waves prepare in the direction of the excitation source 15 out. The proportion of through the bypass duct 2 recorded pressure waves compared to the main flow channel 1 continues to flow through pressure waves in the 2 through the arrow 30 characterized.

In the bypass duct 2 becomes gas in the fluid 26 , for example air caught and trapped. Gas in the fluid, for example air, can thus be effectively separated from the fluid. As a result of the reflection of pressure waves through the bypass duct 2 this has the main flow channel 1 in terms of propagation direction 23 downstream of the branch 6 flowing fluid reduced pressure waves, so pressure waves with a reduced amplitude. These pressure waves are indicated by the reference numeral 27 characterized. In principle, the flow direction of the fluid in the main flow channel 1 not with the propagation direction of the pressure waves 23 be identical. The main flow channel 1 So it can be a first end 28 and a second end 29 exhibit. That the mainstream channel 1 fluid flowing through it may be from the first end 28 to the second end 29 or in the opposite direction.

The angle α is in the 1 and 2 greater than 0 degrees (> 0 °) and less than 90 degrees (<90 °), preferably between 10 degrees (10 °) and 80 degrees (80 °). This angular range promotes the capture and reflection of pressure waves from the excitation source 15 , In particular, such a reflection of the pressure waves back to their excitation source 15 allows.

An arrangement with an angle α of 90 degrees (90 °) is in the 3 shown. An advantage of this variant is the use of gravity to catch air in the bypass duct. A certain proportion of air always exists in the working fluid. As air is lighter, it will separate out of the working fluid and move up. Another advantage in this variant is the mode of action as a Helmholtz resonator.

In the in the 4 shown variant, the angle α an amount greater than 90 degrees (> 90 degrees) and less than 180 degrees (<180 degrees), preferably an amount between 100 degrees (100 degrees) and 170 degrees (170 degrees). By obstacles, for example a valve 41 and / or a bend 42 and / or a change in cross section of the flow channel 1 pressure waves are reflected. This is through the arrows 25 characterized. This variant is suitable for catching the reflected wave by obstacles. This allows one before the branch 6 arranged hydraulic component to be protected from high pressure fluctuations. The venturi effect further allows fluid, for example fuel, to be withdrawn from the bypass passage. Air can be collected as an effective damping medium by the resulting negative pressure in the bypass duct.

In the in the 5 shown variant, the pressure waves propagate the excitation source 15 starting from the second end 29 in the main flow channel 1 from, so for example, against the flow direction of the flow channel 1 flowing fluid. In this case, the mode of action corresponds to that in the 5 shown variant of the in the 1 and 2 shown embodiment.

In all variants shown, the main flow channel is due to the lower vibration load through the secondary flow channel 2 less prone to damage from pressure surges. He also has a reduced NVH problem.

Another advantage is described below with reference to 6 explained. In this variant, the flow direction is at the first end 28 in the main flow channel 1 entering fluid with the reference numeral 31 and that the main flow channel 1 at the second end 29 leaving fluid with the reference numeral 32 , In the in the 6 In the variant shown, the Venturi effect is used to generate negative pressure in the secondary flow channel and air as an effective damping medium in the secondary flow channel 2 to catch.-The angle α is greater than 90 degrees (90 degrees). As a result of the Venturi effect, fluid can escape from the bypass duct 2 sucked out or pulled out This is by arrows 35 characterized. This creates a negative pressure or vacuum at the second end 4 of the bypass duct. As fluid is withdrawn or pulled out, the volume of air increases. The increased air volume is indicated by the reference numeral 34 characterized. Due to the volume change of 33 on 34 in the bypass duct 2 the damping properties of the device are improved.

The in the 7 shown variant corresponds substantially to the in the 1 and 2 shown embodiment with the difference that the flow direction 31 of the fluid is set so that the fluid is the main flow channel 1 from the first end 28 to the second end 29 flows through. The flow direction in the branch 6 is with the reference number 36 The flow direction in the bypass passage is indicated by the reference numeral 37 characterized.

In the in the 7 shown variant, the air 26 therefore, it is air excreted from the fluid, which is then available and used to improve damping. The in the secondary flow channel 2 trapped air 26 can be both compressed and expanded.

The in the 1 to 7 Variants shown can be combined with each other in any way. Examples are in the 8th and 9 shown. Here are on a main flow channel 1 several identically configured secondary flow channels 2 arranged in series with respect to the flow direction.

In the in the 9 shown variant are each side flow channels 2 with different angles α with respect to the main flow channel 1 or its central axis 14 arranged in a row. In the in the 9 The variant shown above is in the flow direction 31 a bypass duct 2 with an angle α greater than 90 ° and downstream of this a bypass duct 2 with an angle α arranged smaller than 90 °. In the 9 below, a reverse arrangement is shown, ie in the flow direction 31 a bypass duct 2 with an angle α less than 90 ° upstream of a bypass duct 2 with an angle α less than 90 ° shown.

Another variant is in 10 shown. In this variant, several, in the present case three, side flow channels 2 in relation to the central axis 14 of the main flow channel 1 staggered to each other. In other words, the shown secondary flow passages are at the same axial position with respect to the central axis 14 of the main flow channel 1 arranged, but each have a different radial component of their respective central axes 13a . 13b and 13c on. The branch 6 is in the 10 designed such that it has a plurality of radially offset from each other arranged connection openings 9a . 9b and 9c having.

In all variants, the individual secondary flow channels can have any dimensions and in particular can differ from each other, for example, have different lengths and / or cross-sectional areas.

The in the 1 to 10 shown variants can be combined with each other. For example, in the 8th and 9 shown side flow channels 2 also be arranged offset radially to one another. The main and / or Nebenströmungskanäle may have a circular cross-section perpendicular to their respective axis or a different shape. They can comprise stiff or deformable material. In certain circumstances, malleable material is more effective as it can expand and contract itself. The angles α can be individually set for the desired application. It can be considered that the flow direction of the fluid need not be identical to the direction of propagation of the pressure waves. In this context, the flow dynamics and / or the dynamics of the pressure waves by a suitable choice of angles α and the arrangement of bypass ducts 2 be specifically influenced. In addition, by an appropriate arrangement, in particular a upward-directed secondary flow channel that uses gravity to trap and retain gas, for example air, in the bypass duct.

The 11 schematically shows a pumping device according to the invention 40 , This comprises a previously described device according to the invention 10 and an excitation source 15 , For example, a piston pump or a centrifugal pump, which causes pressure waves.

The 12 schematically shows a hydraulic device according to the invention 50 , which is a pumping device according to the invention 40 includes. The 13 schematically shows a motor vehicle according to the invention 51 , The motor vehicle according to the invention 51 includes a hydraulic device according to the invention 50 and / or a pump device according to the invention 40 and / or a device according to the invention 10 ,

LIST OF REFERENCE NUMBERS

1

Main flow channel

2

Auxiliary channel

3

first end

4

second end

5

closure device

6

junction

7

first connection opening

8th

second connection opening

9

third connection opening

10

Device for damping pressure fluctuations

11

Direction of gravity

12

Propagation direction of the sound waves

13

central axis

14

central axis

15

excitation source

20

pressure waves

21

pressure waves

22

pressure waves

23

propagation direction

24

propagation direction

25

propagation direction

26

gas

27

pressure waves

28

first end

29

second end

30

Distribution of pressure waves

31

flow direction

32

flow direction

33

Output air volume

34

extended air volume

35

flow direction

36

flow direction

37

flow direction

40

pumping device

41

Valve

42

bend

50

hydraulic device

51

motor vehicle

α

angle

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102015000418 A1 [0005]

Claims (16)

Device for damping pressure fluctuations (10), characterized in that the device (10) comprises a main flow channel (1) and at least one secondary flow channel (2), wherein the secondary flow channel (2) has a first end (3) and a second end (4) ), wherein the first end (3) via a branch (6) with the main flow channel (1) is fluidically connected and the second end (4) by means of a closure device (5) is closable. Device (10) according to Claim 1 , characterized in that the device (10) comprises a closure device (5) for closing the second end (4). Device (10) according to Claim 1 or Claim 2 , characterized in that the main flow channel (1) in the region of the branch (6) comprises a central axis (14), the secondary flow channel (2) in the region of the branch (6) comprises a central axis (13) and the central axis (14) of the main flow channel (1) and the center axis (13) of the bypass duct (2) enclose an angle (α) between 10 degrees and 170 degrees. Device (10) according to Claim 3 , characterized in that the angle (α) is between 20 degrees and 80 degrees or between 80 degrees and 100 degrees or between 100 degrees and 170 degrees. Device (10) according to one of Claims 1 to 4 , characterized in that the main flow channel (1) comprises a central axis (14) and / or the secondary flow channel (2) comprises a central axis (13) and the main flow channel (1) and / or the secondary flow channel (2) has a circular cross section in a section perpendicular to the central axis (13, 14). Device (10) according to one of Claims 1 to 5 , characterized in that the main flow channel (1) and / or the secondary flow channel (2) comprises rigid and / or deformable material. Device (10) according to one of Claims 1 to 6 , characterized in that the device (10) comprises at least two bypass ducts (2). Device (10) according to Claim 7 , characterized in that the main flow channel (1) comprises a central axis (14) and at least two Nebenströmungskanäle (2) in the axial direction with respect to the central axis (14) of the main flow channel are arranged offset to each other. Device (10) according to Claim 7 or Claim 8 , characterized in that the main flow channel (1) comprises a central axis (14) and at least two side flow channels (2) are arranged offset from each other in the radial direction with respect to the central axis (14) of the main flow channel (1). Device (10) according to one of Claims 1 to 9 , characterized in that the device (10) comprises a branch (6) for at least two secondary flow channels (2). Device (10) according to one of Claims 1 to 10 , characterized in that at least one secondary flow channel (2) with respect to the main flow channel (1) is arranged so that it has a slope in the region of the branch (6). Pumping device (40), characterized in that it comprises a device (10) according to one of Claims 1 to 11 includes. Pumping device (40) after Claim 12 , characterized in that it comprises a piston pump and / or a centrifugal pump. Hydraulic device (50), characterized in that it comprises a device (10) according to one of Claims 1 to 11 and / or a pump device (40) according to one of Claims 12 or 13 includes. A method for damping pressure fluctuations, characterized in that a device according to one of Claims 1 to 11 and / or a pump device (40) according to one of Claims 12 or 13 and / or a hydraulic device (50) Claim 14 is used for damping pressure fluctuations in at least one flow channel. Motor vehicle (51), characterized in that it comprises a device (10) according to one of Claims 1 to 11 and / or a pump device (40) according to one of Claims 12 or 13 and / or a hydraulic device (50) Claim 14 includes.

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