Pump and pumping process

Abstract

A pump comprising a fluid inlet (1) with an inlet control element (4), a fluid outlet (2) with an outlet control element (5), an interior (3), an oscillator element (6) configured to cause longitudinal oscillations in the fluid in the interior (3) of the pump, and at least one pressure sensor in the interior (3) for monitoring the internal pressure, characterized in that the interior (3) is shaped such that the pressure waves are focused in the area of ​​at least one of the passages (1, 2), wherein at least one wall of the interior (3) is shaped as a concave mirror, and wherein the inlet (1) and / or outlet (2) are arranged at the focal point of the concave mirror, and that the oscillator element (6) is arranged relative to the concave mirror and to the respective at least one passage (1, 2) such that pressure waves generated by it are focused at this focal point.wherein inlet (1) and outlet (2) are arranged side by side less than one inlet or outlet width apart at their edges on a common wall of the interior (3) and the wall of the interior (3) opposite this wall is designed as a concave mirror whose focal point lies in the region of inlet (1) and outlet (2), or inlet (1) and outlet (2) are opposite each other at a protrusion of the wall of the interior (3), wherein the focal point is located exactly in this protrusion.

Description

[0001] The invention relates to a pump and a pumping method for increasing pressure in a fluid.

[0002] There is an almost overwhelming variety of pumps and pumping methods. They are mostly based on the principle that a fluid is compressed or expanded by means of mechanical force. Regarding liquids that are largely incompressible, it should be noted that in this case they are not compressed / expanded, but rather used to compress / expand an object (e.g., hydraulics) or to cause the liquid to rise or fall in a riser pipe.

[0003] All these pumps and pumping methods have in common that achieving a high or low pressure (relative to ambient pressure) requires a correspondingly high level of effort in the pumping process and the design of the pump, which can be a disadvantage in terms of the efficiency and cost of such a pump.

[0004] JP H08-219 100 A discloses a compressor for drawing in and pumping a refrigerant. The compressor has a resonator with an inlet and an outlet for the refrigerant. An oscillator element is mounted in an opening of the resonator as a driving element, which serves to set the refrigerant inside into longitudinal oscillations.

[0005] From AT 356 514 B, a double-acting pump with reciprocating motion of the pumped medium in a cylinder is known. The cylinder, equipped with inlet and outlet valves, is closed at one end by a solid wall and at the other end by a diaphragm or a piston. The diaphragm or piston is kept in vibration at the natural frequency of the pumped medium column, and these longitudinal vibrations produce a pumping effect.

[0006] US 5,525,041 A discloses a pump comprising a chamber with an inlet and outlet for the medium to be pumped, as well as a sound transducer. The sound transducer is attached to one of the two ends of the chamber and serves to generate a traveling wave in the medium.

[0007] US Patent 2007 / 0235252A1 discloses an acoustic fluid machine that utilizes fluctuations in pressure amplitude based on acoustic resonance. The machine has an acoustic resonator with an upper and lower end, the lower end having a larger diameter than the upper end. The acoustic resonator also has an inlet and an outlet. Inside the resonator, a piston vibrates axially at high speed but with a very small amplitude.

[0008] DE 691 22 534 T2 discloses a compressor for refrigerant, comprising a chamber for receiving this refrigerant, the chamber having at least one inlet and at least one outlet. The compressor further comprises an excitation device for generating a traveling wave in the liquid refrigerant located in the chamber.

[0009] US Patent 5,020,977 A discloses a refrigerant compressor comprising a chamber for a gaseous refrigerant, a driving means for generating an acoustic traveling wave in the refrigerant contained in the chamber, and means for converting the traveling wave into a standing acoustic wave. The compressor further comprises one or more inlets at the pressure nodes of the standing wave, and one or more outlets at the opposite nodes (antinodes) of the standing wave. The inlets and outlets may be equipped with check valves.

[0010] US 2004 / 0086399A1 discloses a pump with an outer body that defines a pump chamber and has an inlet and outlet. The pump further comprises a casing that defines a drive chamber, wherein an outer surface of the casing is located at least partially within the pump chamber. The drive chamber contains an excitable medium in which a standing wave can be generated by means of an excitation source, whereby the outer surface of the casing is deformed and a pumping fluid is pumped from the inlet to the outlet.

[0011] US 2003 / 0053915A1 discloses an ultrasonic pump comprising a housing with a chamber, the chamber having a first and a second opening. The housing further includes an inlet through which the medium can enter the chamber, and an outlet. The pump further includes a transducer for generating longitudinal ultrasonic waves with a focused beam pattern and a focal zone, the shape of the chamber corresponding to the focused beam pattern.

[0012] The object of the present invention was to overcome the disadvantages of the prior art and to provide a pump and a pumping method by means of which a user is able to easily achieve a pressure increase or pressure decrease.

[0013] This task is solved by a pump and a pumping method according to the claims.

[0014] The pump according to the invention comprises a fluid inlet with an inlet control element, a fluid outlet with an outlet control element, an interior space, an oscillator element configured to set the fluid in the interior space of the pump into longitudinal oscillations, and at least one pressure sensor in the interior space for monitoring the internal pressure. The interior space is shaped such that the pressure waves are focused in the area of ​​at least one of the passages, wherein at least one wall of the interior space is shaped as a concave mirror, and wherein the inlet and / or the outlet are arranged at the focal point of the concave mirror.The oscillator element is arranged relative to the concave mirror and to the relevant at least one aperture such that pressure waves generated by it are focused at this focal point, wherein the inlet and the outlet are arranged side by side less than an inlet or outlet width apart at their edges on a common wall of the interior, and the wall of the interior opposite this wall is designed as a concave mirror whose focal point lies in the region of the inlet and outlet, or the inlet and outlet are located opposite each other at a protrusion of the wall of the interior, wherein the focal point is located exactly in this protrusion.

[0015] The fluid inlet will also be referred to simply as the "inlet" in the following text. The fluid outlet will also be referred to simply as the "outlet" in the following text. Since the inlet element and the outlet element essentially perform the same function, they can be collectively referred to as "control elements." The same applies to the fluid inlet and the fluid outlet. Since a fluid is intended to flow through both, they can collectively be referred to as "passages."

[0016] Fluid inlet and fluid outlet are familiar to those skilled in the art. In the simplest case, these are the openings of two pipes through which the fluid can flow into and out of the interior.

[0017] The inlet control element and the outlet control element are designed to regulate the fluid flow through the inlet / outlet. They are capable of assuming a state in which the inlet or outlet is fluid-tight (state: "closed") and a state in which fluid flow into the inlet or outlet is possible (state: open).

[0018] A preferred control element is a passive control element. A passive control element is opened or closed solely by the prevailing pressure or by pressure differences. With such an element (preferably both control elements are passive), a very cost-effective and simple pump design is possible. Preferred passive control elements are valves (without active switching elements).

[0019] For some applications, however, an active control element may be preferred. Such a control element is opened and closed by a control unit. With such elements, very fast and ambient pressure-independent control is possible. Preferred passive control elements are valves with an actively controlled closing mechanism or mechanical switches, in particular gate valves or flaps.

[0020] The oscillator element is necessary for pressure build-up. By setting the fluid inside the pump into longitudinal oscillations, it creates areas of higher pressure ("wave crests" of the pressure waves) and lower pressure ("wave troughs" of the pressure waves) in certain areas of the interior.

[0021] Preferred oscillator elements are designed to periodically increase and decrease the internal volume, and / or are configured as movable bodies and / or as loudspeakers. Depending on the application, an oscillator based on the acceleration of the fluid elements due to electric fields is preferred.

[0022] The pumping method according to the invention with such a pump is based on the following steps: - Applying an inlet pressure PE at the inlet and initially inside the pump, - Generation of pressure waves inside the pump, - Opening of the outlet control element when the local pressure inside the outlet control element is greater than the outlet pressure PA behind the outlet control element in the outlet (wave crest at the outlet), - Opening of the inlet control element when the local pressure inside the inlet control element is less than the inlet pressure PE behind the inlet control element in the inlet (trough at the inlet).

[0023] It is self-evident that the term "behind" in the preceding text means "beyond the interior." The pressure PE or PA prevails at the inlet or outlet beyond the interior, and these pressure domains are separated from the interior by the control elements until the local pressure at the respective control elements is such that fluid flow from the inlet to the interior or from the interior to the outlet is possible.

[0024] Since the internal pressure will stabilize at (PA+PE) / 2 with this principle, the oscillator element should be capable of generating pressure fluctuations with a sound pressure amplitude greater than (PA-PE) / 2, at least locally. As a sound pressure level of approximately 194 dB corresponds to the standard atmospheric pressure of 1013.25 hPa, it is preferred that the interior be shaped such that the pressure waves are focused in the inlet and / or outlet areas. In this way, a very high sound pressure can be achieved locally in the areas crucial for this invention.

[0025] For this purpose, at least one wall of the interior is shaped as a concave mirror (for sound or pressure waves), in particular as a spherical mirror or a parabolic mirror. In the simplest case, it is simply curved outwards, so that the interior has a concave curvature there.

[0026] The inlet and / or outlet are located at the focal point of such a concave mirror. The oscillator element is positioned relative to the concave mirror and to the inlet and / or outlet in such a way that the pressure waves it generates are focused at this focal point.

[0027] The inlet and outlet are arranged side by side (less than one inlet or outlet width) with their edges spaced apart on a common wall of the interior, and the wall of the interior opposite this wall is designed as a concave mirror whose focal point lies in the area of ​​the inlet and outlet.

[0028] According to another alternative embodiment, the inlet and outlet are located opposite each other at a protrusion of the wall of the interior, with the focal point being located exactly in this protrusion.

[0029] The oscillator element is arranged in such a way that its pressure waves (or sound waves) are focused by the concave mirror at the focal point.

[0030] According to a preferred embodiment, the oscillator element is designed such that the modes emitted by it do not overlap with the spatial modes of the interior space, or only to a partial extent of 10% or less.

[0031] If one considers the power spectrum of such an oscillator element as a function of frequency and considers the frequencies of the eigenmodes of the interior, then the area of ​​this power spectrum curve may lie in the region of eigenfrequencies of the interior to less than 10% (in particular less than 1%).

[0032] This prevents standing waves, which is advantageous for some applications and interior shapes. Preferred interior shapes in this case are a sphere or a cube (possibly with one or two concave mirror-shaped walls), with these geometric forms defining the shape of the recess. Such simple shapes, unlike complex configurations, exhibit few spatial modes.

[0033] Several pumps according to the invention can also be connected in series to obtain a higher output pressure. The internal pressure increases with each subsequent pump, whereby, apart from the change in sound impedance due to the increasing pressure, it makes no difference to the oscillator elements what the internal pressure is, since the sound pressure or the pressure waves are modulated onto the internal pressure.

[0034] A particularly advantageous system comprises at least two pumps according to the invention, wherein the oscillator elements of the two pumps are synchronized with each other (same frequency of the pressure waves) and the phases of the oscillator elements of successive pumps are set such that at the time when there is a locally high pressure at the outlet of the preceding pump, there is a low local pressure at the inlet of the following pump, wherein said outlet is connected to this inlet or the outlet of the preceding pump is the inlet of the following pump.

[0035] In this way, the fluid is subjected to the lowest possible internal pressure as it flows into the following pump, since this pressure is locally low at that time.

[0036] According to a preferred embodiment, the pump comprises at least two internal chambers separated by a channel and a valve, such that when there is a local overpressure at the outlet of the first internal chamber, air flows into the subsequent second internal chamber. However, this second internal chamber contains no further oscillator element, so that a nearly static pressure prevails throughout the entire volume, which can be increased up to a limit via the connection to the first internal chamber. The advantage of this embodiment is the provision of a continuous, non-fluctuating pressure at the outlet of the second internal chamber. Instead of the first internal chamber, several internal chambers connected in series or parallel can be used. Likewise, instead of the second internal chamber, several internal chambers connected in series or parallel can be used.

[0037] Preferably, the pump also includes at least one pressure sensor for monitoring the internal pressure. The pressure sensor data is used in particular for controlling the valves.

[0038] Preferred fluids are liquids or gases, especially air or water.

[0039] Examples of preferred embodiments of the pump according to the invention are shown in the figures. Fig. Figure 1 schematically shows a pump that does not conform to the invention. Fig. Figure 2 schematically shows a preferred embodiment. Fig. Figure 3 schematically shows another preferred embodiment. Fig. Figure 4 schematically shows an important detail of the invention's functionality. Fig. Figure 5 shows a preferred pump system.

[0040] Fig. Figure 1 schematically shows a pump not according to the invention and serves only for explanation. The pump shown there has a fluid inlet 1 on the left with an inlet valve 4 as an inlet control element, a fluid outlet 2 on the right with an outlet valve 5 as an outlet control element, an interior space 3 with concave walls in the center, and an oscillator element 6 in the lower part of the interior space.

[0041] This oscillator element generates pressure fluctuations in the interior, which, according to the in Fig. In accordance with the principle shown in section 4, valves 3 and 4 open and close, and fluid is transferred from fluid inlet 1 to interior 3 and from interior 3 to fluid outlet 2.

[0042] In this example, an additional pressure sensor 7 is installed in the interior 3 to monitor the internal pressure.

[0043] The data from this pressure sensor 7 can be used to monitor the pump as well as to control valves 3 and 4. For controlling valves 3 and 4 in particular, it is preferred if a pressure sensor is located on the wall directly next to or in front of the valve in order to accurately determine the local pressure at the valves.

[0044] Fig. Figure 2 schematically shows a preferred embodiment in which the fluid inlet 1 and fluid outlet 2 are both arranged on the same side of the interior 3 (right) and the opposite wall of the interior 3 is spherically concave and serves as a concave mirror. A pressure wave front radiated by means of the oscillator element 6 is reflected by the concave mirror and simultaneously focused such that at the focal point, which lies in the region of the fluid inlet 1 and fluid outlet 2, it reaches a multiple of the radiated amplitude.

[0045] In the state of high local pressure at the focal point, the exhaust valve 5 is forced open and fluid flows against the prevailing pressure PA into the fluid outlet 2; in the state of low local pressure at the focal point, the inlet valve 4 is forced open and fluid flows from the fluid inlet 1 into the interior 3.

[0046] Fig. Figure 3 schematically shows another preferred embodiment, the mode of operation of which is the same as that in Fig. 2 is. Only the arrangement of fluid inlet 1 and fluid outlet 2 (and oscillator element 6) differs from Fig. 2. The focal point of the concave mirror lies here in a protrusion of the interior 3, on the side walls of which fluid inlet 1 and fluid outlet 2 are arranged.

[0047] In Fig. Figure 4 illustrates an important detail of the invention's operation with reference to the fluid inlet 1, which includes an inlet valve 4 as an inlet control element. At the center of the figure is a sine wave representing the pressure profile directly upstream of the inlet in the interior. This pressure alternates between locally high pressure (wave crest) and locally low pressure (wave trough). It is assumed that the pressure amplitude of the wave is greater than the pressure P prevailing in the inlet 1.

[0048] If the local pressure in the interior corresponds to a wave crest (upper representation of inlet 1), the resulting pressure acts in the direction of the arrow on the inlet valve 4 and closes it, so that no fluid can flow back into the inlet.

[0049] If the local pressure in the interior corresponds to a wave trough (lower representation of inlet 1), the resulting pressure acts in the direction of the arrow on the inlet valve 4 and pushes it open, so that fluid can flow into the interior.

[0050] The same applies to the outlet.

[0051] In Fig. Figure 5 shows a system of two pumps connected in series. For clarity, the central opening is not labeled, as it serves as both the outlet of the first pump (left) and the inlet of the second pump, and therefore should bear the reference symbols 1 and 2. At the center of each pump, the local pressure distribution is represented by two waves, with wave crests indicating high-pressure domains and wave troughs indicating low-pressure domains.

[0052] Fluid flows into the left pump through the left inlet 1, provided the local internal pressure at inlet 1 is lower than the inlet pressure. This fluid exits the left pump through its outlet (center) via outlet valve 5, which simultaneously serves as the inlet valve 4 of the right pump, when the local internal pressure at the outlet of the left pump is greater than the local internal pressure at the inlet of the right pump. This point in time is represented by the waves in the figure. The oscillator elements (not shown) are set so that their phases are coupled, and the resulting phase shift causes a wave crest at the outlet of the left pump to coincide with a wave trough at the inlet of the right pump. The right pump discharges the fluid at a higher pressure than could be achieved with either pump alone when a local pressure maximum is present at the right outlet 2.

[0053] In Fig. 6 is a variation of Fig. Figure 5 shows a system of two chambers 3 connected in series, in which the pressure is only changed in the first chamber 3, and a static pressure prevails in the second chamber 3 except for the air movements through its inlet and outlet. This system delivers a constant pressure at the outlet. Of course, it is also possible to connect the second chamber to a system according to Fig. 5 to add or to attach multiple interior spaces without oscillating pressure, which improves the stability of the air pressure.

Claims

[1] Pump comprising a fluid inlet (1) with an inlet control element (4), a fluid outlet (2) with an outlet control element (5), an interior space (3), an oscillator element (6) configured to cause longitudinal oscillations in the interior space (3) of the pump, and at least one pressure sensor in the interior space (3) for monitoring the internal pressure, characterized bythat the interior space (3) is shaped such that the pressure waves are focused in the area of ​​at least one of the openings (1, 2), wherein at least one wall of the interior space (3) is shaped as a concave mirror, and wherein the inlet (1) and / or outlet (2) are arranged at the focal point of the concave mirror, and that the oscillator element (6) is arranged relative to the concave mirror and to the relevant at least one opening (1, 2) such that pressure waves generated by it are focused at this focal point, wherein the inlet (1) and outlet (2) are arranged side by side less than one inlet or outlet width apart at their edges on a common wall of the interior space (3), and the wall of the interior space (3) opposite this wall is designed as a concave mirror whose focal point lies in the area of ​​the inlet (1) and outlet (2), or the inlet (1) and outlet (2) are opposite each other at a protrusion of the wall of the interior space (3),the focal point is located precisely in this protrusion. [2] Pump according to claim 1, characterized by , that the control elements (4, 5) are designed to regulate the fluid flow through the passages (1, 2), being configured to assume a state in which the respective passage (1, 2) is fluid-tight closed, and a state in which fluid flow through the passage is possible. [3] Pump according to any of the preceding claims, characterized by , that at least one control element (4, 5) is passive, in particular a valve, so that it is only opened and closed by the locally prevailing pressure, and / or that at least one control element (4, 5) is active and is opened and closed by a control unit. [4] Pump according to any of the preceding claims, characterized by, that the oscillator element (6) is designed such that it periodically enlarges and reduces the interior space (3), and / or includes movable bodies in the interior space (3), and / or is designed as a loudspeaker, and / or is an oscillator based on acceleration of the fluid due to electric fields. [5] Pump according to any of the preceding claims, characterized by that the concave mirror is a spherical mirror or a parabolic mirror. [6] Pump according to any of the preceding claims, characterized by , that the oscillator element (6) is designed such that the modes emitted by it overlap with the room modes of the interior space (3) to a proportion of 10% or less. [7] Pump according to any of the preceding claims, characterized by, that the pump comprises at least two interior spaces (3) separated by a channel and a valve, such that in the event of a local overpressure at the outlet (2) of the first interior space (3) the air flows into the following second interior space (3), wherein with respect to the flow direction of the lift there is at least no oscillator element (6) in the last interior space (3), so that a nearly static pressure prevails in the relevant interior space (3), which can be increased to a limit value via the connection to the first interior space (3). [8] Pump system comprising at least two pumps according to one of the preceding claims, the outlet (2) of the preceding pump opens into or corresponds to the inlet (1) of the following pump, wherein the oscillator elements (6) of at least two successive pumps are synchronized with each other and the phases of the oscillator elements (6) of adjacent pumps are set such that when there is a locally high pressure at the outlet (2) of the preceding pump, there is a low local pressure at the inlet (1) of the following pump. [9] Pumping method with a pump or pumping system according to any of the preceding claims, comprising the steps: - Applying an inlet pressure PE at the fluid inlet (1) and initially inside (3) the pump, - Generation of pressure waves inside (3) the pump, - Opening of the outlet control element (5) when the local pressure in the interior (3) at the outlet control element (5) is greater than the outlet pressure PA behind the outlet control element (5) in the fluid outlet (2), - Opening of the inlet control element (4) when the local pressure in the interior (3) at the inlet control element (4) is less than the inlet pressure PE behind the inlet control element (4) in the fluid inlet (1).

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