DE202022100233U1 - Impeller for an aerator - Google Patents

Abstract

Impeller (1) comprising:
a rotationally symmetrical housing (10) with an inlet (12) and an outlet (14),
a mandrel (20) extending from the outlet (14) towards the inlet (12) axially and centrally with respect to the housing (10), the mandrel further having a connection area (52) on which a rotating shaft (50) connectable to the mandrel (20);
a plurality of vanes (22a, 22b, 22c) attached to the mandrel (20) and to the casing (10), the plurality of vanes (22a, 22b, 22c) being aligned such that any two adjacent vanes ( 22a, 22b) of the plurality of blades (22a, 22b, 22c) together with the mandrel (29) and the housing (10) form a channel (32a, 32b, 32c),
each channel (32a, 32b, 32c) having an inlet opening facing the inlet and an outlet opening (36a, 36b, 36c) facing the outlet; characterized in that
each channel widens in the direction of the outlet (14), so that the total exit area of all exit openings (36a, 36b, 36c) is larger than the entry area of all entry openings.

Description

The present invention relates to an impeller for an aerator and in particular to an impeller for use in an aerator for the agitation, aeration and supply of liquid media with gases, liquids or powders.

A system in which gas is transferred into a liquid is generally referred to as an aeration system or aerator.

The gassing or aeration of liquids is of particular importance in chemistry, industry and biotechnology, e.g. in fish farming or in sewage treatment plants. The aim here is to achieve the most homogeneous possible mixing of gas and liquid.

In fish farming, for example, the supply of oxygen is used to prevent the development of diseases. The aeration of drinking water is also an example of an application in which an increased oxygen content of drinking water is sought.

The aeration itself usually takes place by means of stirring systems which are set in rotation and which, depending on the application, are provided with different stirring elements and are driven by a motor, in particular by means of an electric motor.

The stirring elements are, for example, circulating wheels, impellers with disk, large or small-bladed rotor blades and/or inclined blades.

Such systems are essentially based on the displacement principle, i.e. the liquid is essentially displaced in order to thus cause turbulence and, for example, mix oxygen into the liquid.

Alternatively, air and/or special gases are sucked in from outside the water surface and released again underwater. In this case, gases can be introduced by means of a simple air intake pipe, the inlet of which is above the liquid level and the outlet of which is below the water surface.

Such systems have a high expenditure of energy, because systems based on the displacement system require, for example, an increased expenditure of energy in order to overcome the resistance of the liquid. This is often seen as a problem in sewage treatment plants in particular. The air intake principle, on the other hand, requires pumps and motors, which significantly increase the complexity of the system and its energy consumption.

Furthermore, the maintenance of the systems of the prior art is usually difficult to handle, since more powerful and therefore heavy electric motors are usually required to drive the conventional stirring systems.

The prior art devices accordingly have many disadvantages.

It is therefore the aim of the present invention to provide a device which at least partially solves the disadvantages of the prior art. The aim of the present invention is also to develop a device which introduces gases into liquid media (e.g. water) efficiently, i.e. with low energy consumption and CO2 emissions, and moves and aerates these media.

Such a device is provided by means of an impeller and/or an aerator comprising the impeller according to the independent claims. Embodiments are part of the dependent claims.

• ein rotations-symmetrisches Gehäuse mit einem Einlauf und einem Auslauf; ein Dorn, der sich vom Auslauf in Richtung Einlauf axial und zentral in Bezug auf das Gehäuse erstreckt, wobei der Dorn ferner einen Verbindungsbereich aufweist, an dem eine rotierende Welle an den Dorn verbindbar ist.

According to the present invention there is provided an impeller comprising:

• a rotationally symmetrical housing with an inlet and an outlet; a mandrel extending from the outlet toward the inlet axially and centrally of the housing, the mandrel further having a connection portion at which a rotating shaft is connectable to the mandrel.

The impeller further includes a plurality of blades attached to the mandrel and the casing, the plurality of blades being aligned such that any two adjacent blades of the plurality of blades form a channel together with the mandrel and the casing. Each channel has an inlet opening facing the inlet and an outlet opening facing the outlet.

The impeller is characterized in that each channel widens towards the outlet such that the total exit area of all exit openings is larger than the entry area of all inlet openings.

The invention is an impeller, i.e. a rotating system which can be moved under water by means of a driving force and creates a vortex funnel. For the operation of the impeller, the angle between the water level and the axis of the impeller is variable and the impeller still works when the flow is at an angle.

The impeller is below the liquid level when in use. The distance to the surface of the water level must be selected in such a way that a vortex can arise.

The housing of the impeller according to the invention is rotationally symmetrical and has an inlet and an outlet. The impeller also has a mandrel extending centrally with respect to the housing from the outlet towards the inlet of the impeller.

The mandrel also has a connection area. A rotating shaft can be connected to the connection area of the mandrel, which rotates the impeller by means of a drive. According to one embodiment, the connection area can be arranged either at the inlet or at the outlet of the impeller.

The detachable connection of the impeller to a shaft in the connection area enables the impeller to be used on existing prior art shafts, whereby old inefficient systems can be replaced by the advantageous impeller according to the invention.

A plurality of vanes are attached to the mandrel in the housing. In one embodiment, the vanes are annularly attached to the mandrel.

The vanes are also attached to the casing so that two adjacent vanes together with the mandrel and casing form a channel through which liquid can flow. Each channel has an entry opening facing the inlet. On the essentially opposite side, facing the outlet, each channel has an outlet opening.

According to the invention, each channel widens in the direction of the outlet. The total exit area of all exit openings is therefore larger than the entry area of all entry openings. Each channel widens in the direction of flow (i.e. small inlet and large outlet).

Correspondingly, the number of channels in an impeller according to the invention is equal to the number of blades. The number of blades can vary according to the application of the impeller.

Thus, when the impeller is set in rotation, a negative pressure is created in the duct and in particular in the inlet of the duct, the liquid being drawn through the inlet and expelled from the outlet.

In particular, a suction is generated by this acceleration and a vortex vortex is created, comparable to the turbulent vortices in nature. The mixture of gas and liquid is sucked in from the surface of the liquid downwards in the axial direction and blown out in the axial direction downwards, with a significant difference to the commercially available devices.

When the impeller rotates, a vortex vortex is created with a highly turbulent boundary layer between the vortex and the liquid. In the vortex turning faster and faster from top to bottom (according to Bernoulli) there is a downward suction.

Due to the interaction between air or gas and liquid, currents arise at this turbulent boundary layer, which direct the liquid downwards at the boundary layer at an angle of approx. 30 -35 degrees.

Above the impeller, air or gases mix with the liquid in the vortex vortex. This mixing is intensified in the impeller itself. The mixing of air or gas and liquid is increased even more by means of the fine air or gas bubbles generated in large numbers by and in the impeller. In the ideal case, up to a complete saturation level of the liquid.

The amount of air sucked in and the size of the resulting vortex depends on the size of the impeller, the speed, the viscosity of the liquid, etc., as well as the position and distance to the water surface.

This turbulence by means of the impeller according to the invention, which is set in rotation, results in a high ventilation capability and homogeneous introduction of gases or powders.

The run-in efficiency of the impeller is determined by the size of the impeller's catch area, the size of the impeller's throat area, the size of the total catch area, and/or the size of the throat areas between the blades of the impeller. According to a further embodiment, the inlet has inlet lips. The hydro-/aerodynamic shape of the inlet lip and the impeller housing also have an effect on the efficiency of the inlet.

The catch area is the area of the inlet within the damming line of the inlet lips of the impeller. The throat area is the area with the smallest cross-sectional area between the inlet lips.

According to a further embodiment, it can be advantageous to design the catch surface of the impeller to be smaller than the total catch surface between the blades of the impeller of the inlet. According to a further embodiment, the throat area of the inlet of the impeller is smaller than or equal to the catch area of the impeller.

At the same time, according to a further embodiment, the throat area of the impeller is equal to or smaller than the total inlet area between all blades of the impeller.

According to a further embodiment, the entire course of the cross section from the inlet of the impeller to the outlet surface of all blades has a course which is as constant and smooth as possible.

According to an embodiment of the present invention, the angle of the vanes with respect to the casing can be fixed or adjustable.

The double-curved and smooth surface, arrangement and angle of attack of the blades result in an axial flow through the impeller with little resistance. The exact hydro/aerodynamic shape of the inlet lip and the shape of the housing depends on the geometry of the container and the medium and can be optimized for the respective application.

The blades can be arranged at a certain angle. However, in the various embodiments, their arrangement must meet the above-mentioned framework requirements for the muzzle and neck surfaces. The blades can be adjustable.

The impeller in all its embodiments has a large number of advantages. Liquids or gases, for example, are simply moved and swirled at high speed, with the gases being introduced into the liquid primarily in a self-aspirating manner.

Furthermore, ventilation can be carried out over a longer period of time without having to exchange external containers such as gas containers. Existing pools can also be easily equipped, among other things.

The turbulence of the present device also has the advantage that, e.g.

Experiments show that higher gas transfer rates could be achieved with the hyperbolic vortex funnels than with conventional ventilation systems in use today.

3D printing is an ideal, cost-effective manufacturing process for the impeller, but other manufacturing processes such as casting are also possible.

The impeller can be made of metal or plastic - also food-safe. This means that it can be used not only in normal water, but also in salt water, toxic substances or in aquariums with live fish.

An antibacterial effect can also be achieved by silver-plating the impeller.

The construction is quite easy to implement. The size of the impeller and number of blade orientations can be easily adjusted to the required performance and needs of each application. The impeller is therefore scalable and can therefore be used for a wide variety of applications.

The shape of the stirred tank is not critical; Experiments have shown that the best performance is in cylindrical, egg-shaped or round containers, as there are no "dead" corners. These are therefore suitable with the generated vortices, which also have a round shape.

In order to set the impeller in rotation, the use of a rotating shaft is advantageous. The rotating shaft can be connected to the impeller at the connecting portion of the mandrel. The rotating shaft and impeller together essentially form an aerator.

Accordingly, in the present invention there is provided an aerator comprising an impeller according to an embodiment of the invention. The aerator further includes a rotating shaft connected to the impeller at the connection area of the mandrel, the shaft extending axially from the outlet or the inlet and connected to a drive.

According to one embodiment, the rotary shaft is connected and in particular releasably connected to the connection area of the mandrel by means of fastening means. According to an alternative embodiment, the rotary shaft is integral with the mandrel, i.e. they form a single element.

The advantage of connecting the shaft in a detachable manner is that in the event of damage or deterioration, the impeller can be clogging of individual channels can be easily removed (this is especially useful in sewage treatment plants). The advantage of an integral connection is the improved stability of the aerator.

The length of the shaft in turn depends on the application. A good immersion depth of the impeller in the tank with liquid is 5 to 10 times the diameter of the casing, but can be optimized for the specific application.

By the rotation of the rotating shaft, the impeller together with its blades is driven and the suction effects described above are achieved. In particular, the liquid or gaseous media are sucked in by the rotation of the impeller around the shaft and accelerated in the axial direction from the inlet towards the outlet. This acceleration is caused in particular by the geometry of the blades, such as their orientation.

By silvering the aerator, an antibacterial effect can also be achieved.

The aerator can be driven by any known method of driving a rotary system about an axis. The installation and mounting of a drive system depends on the desired application.

Due to the higher efficiency, a smaller drive is required for an intended mixing result, which means that less energy is consumed and therefore less CO2 is emitted.

According to one embodiment of the present aerator, there is also the possibility of simply attaching external gassing to the aerator.

• • Durch die Verwendung einer hohlen Antriebswelle bzw. rotierende Welle, die eine Perforation in dem Inneren des Laufrads aufweist, eine direkte Vermischung von einem eingeführten Gas oder Pulver erreicht werden kann.
• • die Atmosphäre oberhalb des Fluiden mit dem Gas beaufschlagt wird, welches dann durch den Unterdruck im Wirbel, wie die in die Flüssigkeit eingemischte Luft, ohne weitere Energiezufuhr mittels der Geometrie des erfindungsgemäßen Laufrads eingesaugt wird.

Gas application as well as powder or liquid supply is also possible by:

• • Direct mixing of an introduced gas or powder can be achieved by using a hollow drive shaft or rotating shaft that has a perforation in the interior of the impeller.
• • the atmosphere above the fluid is acted upon by the gas, which is then sucked in by the negative pressure in the eddy, like the air mixed into the liquid, without further supply of energy by means of the geometry of the impeller according to the invention.

The application of cold or hot gases represents an effective method for cooling/heating liquid media. Here, too, less energy is used and therefore less CO2 is emitted than with competing cooling or heating processes.

• Fischzucht oder Aquarien zur Belüftung, Umwälzung und Reinhaltung des Wassers, Kläranlagen, Viehzucht-Anlagen zur Gülle-Belüftung und bei der Umwälzung und Befreiung von übelriechenden Gasen, Wasserbelebung von Leitungswasser im Haushalt oder Restaurants. Im Allgemeinem ist ein erfindungsgemäßen Aerator überall, wo die Notwendigkeit oder der Wunsch besteht flüssige Medien mit Gasen oder Pulver anzureichern, in Bewegung zu halten oder zu kühlen und erhitzen, einsetzbar.

Possible applications of an aerator according to the invention are, for example:

• Fish farming or aquariums for aerating, circulating and keeping the water clean, sewage treatment plants, animal husbandry systems for manure aeration and for circulating and freeing foul-smelling gases, water revitalization of tap water in households or restaurants. In general, an aerator according to the invention can be used wherever there is a need or a desire to enrich liquid media with gases or powder, to keep them in motion or to cool and heat them.

• 1a und 1b isometrische Ansichten einer beispielhaften Ausführungsform des erfindungsgemäßen Laufrads;
• 2a bis 2c Drauf-, Unter-, Seitenansichten einer beispielhaften Ausführungsform eines erfindungsgemäßen Laufrads;
• 3 eine Schnittansicht des Laufrads aus den vorherigen Figuren.
• 4 eine kranzförmige Anordnung der Schaufeln gemäß einer beispielhaften Ausführungsform eines erfindungsgemäßen Laufrads;
• 5 isometrische Ansichten einer beispielhaften Ausführungsform eines erfindungsgemäßen Aerators;
• 6 eine schematische Darstellung des Betriebs einer beispielhaften Ausführungsform eines erfindungsgemäßen Aerators;

Exemplary embodiments of the impeller according to the invention and the aerator are shown in more detail in the figures. show:

• 1a and 1b isometric views of an exemplary embodiment of the impeller according to the invention;
• 2a until 2c Top, bottom, side views of an exemplary embodiment of an impeller according to the invention;
• 3 a sectional view of the impeller from the previous figures.
• 4 an annular arrangement of the blades according to an exemplary embodiment of an impeller according to the invention;
• 5 isometric views of an exemplary embodiment of an aerator according to the invention;
• 6 12 is a schematic representation of the operation of an exemplary embodiment of an aerator according to the invention;

As in the 1a and 1b shown, the impeller 1 has a housing 10 . The housing 10 is in the form of a substantially sliced ovoid half in this exemplary embodiment.

The impeller 1 also has a 1a shown inlet 12, through which the liquid is sucked in during operation of the impeller 1 and an in 1b outlet 14 shown, through which the sucked liquid is ejected.

The impeller 1 also has a mandrel 20 which is located centrally with respect to the housing 10 and extends from the outlet 14 in the direction of the inlet 12. Vanes 22a, 22b, 22c are positioned between mandrel 20 and housing 10 and connected to mandrel 20 and housing 10. FIG.

As in 2 B shown, form two adjacent blades 22a, 22b together with the housing 10 and the mandrel 20 from a channel 36a.

The impeller 1 also has a connection area 52 through which a rotating shaft can be connected, which impinges the impeller 1 with a rotation during operation.

In 1b In particular, the exit surfaces of the blades 22a, 22b, 22c can be seen, which according to the invention are larger than the entry surfaces of the blades 22a, 22b, 22c, which are shown in 1a you can see. The channels created by the blades 22a, 22b and 22c widen accordingly, so that at the outlet 14, the outlet openings 36a, 36b, 36c are larger than the inlet openings (not shown).

the 2a until 2c show different views of the impeller 1 according to FIG 1a and 1b .

In 2a the inlet 12 is shown, with the channels also being shown schematically. The connection area 52 is arranged in the center of the mandrel 20 and a rotating shaft can be arranged on it, for example. The inlet lip 30 is also visible.

the end 2 B In particular, the outlet openings 36a, 36b, 36c of the blades 22a, 22b, 22c can be seen better.

In 2c the shape of the housing 10 as a carved ovoid half can be clearly seen.

3 is a side sectional view of the impeller 1 of the previous figures. The area A is the catch area of the inlet 12 within the damming line of the inlet lip 30. The neck area B is the area with the smallest cross-sectional area between the inlet lip 30.

Individual channels 32a, 32b are also visible from the figure, as well as the vanes 22a, 22b. The connection area 52 runs through the mandrel 20, to which a shaft can be connected integrally or detachably. This sets the impeller 1 in rotation during operation.

4 shows an exemplary ring-like arrangement of the blades 22a, 22b, 22c. As can be seen, the vanes are skewed, with the spacing between the incoming two adjacent vanes 22a, 22b always being less than the spacing of the outgoing one of the adjacent vanes 22a, 22b. As a result, the entry area of the channels created by the blades 22a, 22b, 22c is smaller than the exit area and the channels widen accordingly. According to the invention, this applies to every embodiment of the impeller 1, regardless of the angle of the blades 22a, 22b, 22c.

5a and 5b show isometric views of an aerator 100. The aerator 100 includes the exemplary embodiment of the impeller 1 according to the 1 until 4 and a rotating shaft 50 which extends axially from the outlet 14 and is connected to the connecting portion of the impeller 1 (not shown). During operation, the rotary shaft 50 transmits a rotation to the impeller 1, so that the liquid is sucked through the channels via the inlet 12 and is separated from the outlet openings 36a, 36b of the outlet 14.

6 shows the aerator off 5 in use, with the aerator attached to a bottom 60 of a container (not shown).

During the rotation of the impeller 1, a vortex 70, in particular a substantially hyperbolic vortex 70, is generated between the inlet 12 and the water level 72 of the container. This is due to the geometry of the impeller 1 and the resulting suction of the liquid.

The axial flow of liquid through the impeller is shown by the dashed arrow. When the liquid that has flowed through emerges at the outlet 14 of the impeller 1, air bubbles form, as a result of which the liquid is aerated to an above-average extent and enriched with air or gas.

Reference List

1

Wheel

10

housing

12

enema

14

outlet

20

mandrel

22a, 22b, 22c

shovels

30

inlet lip

32a, 32b, 32c

channels

36a, 36b, 36c

exit openings

50

wave

52

connection area

60

bottom of a container

70

whirl

72

water level

Claims (14)

Impeller (1) comprising: a rotationally symmetrical housing (10) with an inlet (12) and an outlet (14), a mandrel (20) extending from the outlet (14) towards the inlet (12) axially and centrally with respect extends to the housing (10), the mandrel further having a connection portion (52) at which a rotating shaft (50) on the mandrel (20) is connectable; a plurality of vanes (22a, 22b, 22c) attached to the mandrel (20) and to the casing (10), the plurality of vanes (22a, 22b, 22c) being aligned such that any two adjacent vanes ( 22a, 22b) of the plurality of blades (22a, 22b, 22c) together with the mandrel (29) and the casing (10) form a channel (32a, 32b, 32c), each channel (32a, 32b, 32c) dem has an inlet opening facing the inlet and has an outlet opening (36a, 36b, 36c) facing the outlet; characterized in that each channel widens in the direction of the outlet (14) so that the total exit area of all exit openings (36a, 36b, 36c) is larger than the entry area of all entry openings. Impeller (1) according to claim 1 , wherein the catching area of the impeller (1) is smaller than the total catching area between the blades (22a, 22b, 22c) of the impeller (1) of the inlet. Impeller (1) according to one of the preceding claims, wherein the throat area of the inlet (12) of the impeller (1) is smaller than or equal to the catch area of the impeller (1). An impeller (1) according to any one of the preceding claims, wherein the throat area is equal to or less than the total inlet area between all the blades (22a, 22b, 22c). Impeller (1) according to one of the preceding claims, in which the blades (22a, 22b, 22c) are fixed or adjustable. Impeller (1) according to one of the preceding claims, wherein the impeller (1) has an inlet lip at the inlet 12. Impeller (1) according to one of the preceding claims, produced by a 3D printing process or a casting process. Impeller (1) according to one of the preceding claims, which is made of metal or plastic, in particular food-safe plastic. Impeller (1) according to one of the preceding claims, wherein the impeller (1) has an antimicrobial coating, in particular a coating made of silver. Impeller according to one of the preceding claims, wherein the connection area of the mandrel is arranged on the upstream side or on the downstream side of the impeller. Aerator (100) comprising an impeller according to any one of the preceding claims, further comprising a rotating shaft (50) connected to the impeller (1) at the connection region of the mandrel, the shaft extending axially from the outlet (14) or from the Inlet (12) extends and is connected to a drive (50). Aerator (100) according to claim 11 wherein the drive shaft, which has a perforation in the interior of the impeller for gas admission or powder and/or liquid feed. Aerator (100) according to claim 11 or 12 , wherein the rotary shaft is detachably connected by means of fasteners at the connecting portion of the mandrel. Aerator (100) according to claim 11 or 12 , wherein the rotary shaft is integrally connected to the mandrel.

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