CN117145816A

CN117145816A - Lobe nozzle injection type air amplifier

Info

Publication number: CN117145816A
Application number: CN202311132521.8A
Authority: CN
Inventors: 谢买祥
Original assignee: Individual
Current assignee: Individual
Priority date: 2023-09-05
Filing date: 2023-09-05
Publication date: 2023-12-01

Abstract

The application discloses a lobe nozzle injection type air amplifier, which comprises: a header for mounting support and for introducing compressed air, and a plurality of lobe nozzles having lobe nozzles. The gas collecting tube is a hollow tube and is in ring-shaped arrangement, and an air inlet for compressed air to enter is formed in the gas collecting tube. The plurality of lobe nozzles are arranged in the inner ring of the gas collecting tube along Zhou Xiangyi times of the gas collecting tube at intervals, and the air inlet end of each lobe nozzle is communicated with the gas collecting tube, so that compressed air enters the lobe nozzle through the lobe nozzle and is sprayed outwards under the action of the lobe nozzle, and then ambient air in the external environment is ejected to enter the inner ring from the first side of the gas collecting tube and is mixed with compressed air flow formed by the injection of the lobe nozzle to form a mixed flow, and then is ejected outwards from the second side of the gas collecting tube. The air amplifier has better air flow amplifying effect, and the noise of the lobe nozzle is obviously smaller than that of the narrow slit nozzle under the same maximum jet flow rate.

Description

Lobe nozzle injection type air amplifier

Technical Field

The application relates to the field of air amplifiers, in particular to a lobe nozzle injection type air amplifier.

Background

The air amplifier has the function similar to an exhaust fan, is equipment used for exhausting air and smoke, removing dust and blowing off, is widely applied to the fields of waste gas smoke absorption, dust gas absorption treatment, blowing cooling, moisture blowing off and other industrial application, and is also widely applied to the existing household appliances such as a guide vane-free fan, a blower and the like.

A typical industrial air amplifier principle is shown in fig. 1: when the compressed air passes through the annular narrow slit of the air amplifier, the compressed air is sprayed to the left, and through the coanda effect principle and the special geometric shape of the air amplifier, the ambient air on the right side can be sucked in and blown out of the left side of the air amplifier together with the original compressed air. In general, the smaller the width of the annular slot, the greater the air pressure of the compressed air and the greater the airflow magnification (ambient air flow/compressed air flow) of the air amplifier. For example, the width of the narrow slit of the air amplifier in fig. 1 is only 0.05mm to 0.1mm, the pressure of compressed air is as high as 5.5bar, the air flow speed of the narrow slit exceeds the sound speed, the amplification factor is as high as more than 25 times, but the noise is even remarkable.

The Air Amplifier technology is proposed by the dyson by referring to the principle of the Air Amplifier, and products such as a guide vane-free fan (see figure 2), a blower and the like which are initiated by the company adopt the technology. Compared with an industrial air amplifier, the width of the narrow slit is increased to about 1.3mm, the air flow pressure is greatly reduced to about hundreds Pa, the air flow speed of the narrow slit is reduced to about 30m/s, and thus, the noise of the air flow is greatly reduced, and the air amplifier can be used for household appliances such as a guide vane-free fan and the like.

Whether the industrial Air Amplifier or the Air Amplifier technology of the Dyson, the compressed Air is blown out through a narrow slit to drive surrounding Air flow to flow, so that the effect of amplifying the Air flow is generated. Thus, the boundary between the compressed air and the surrounding air is simply a long straight or circular line through which the molecules of both streams are exchanged. To increase the multiple of air amplification, only the flow speed of high-pressure air flow is increased under the condition of fixed narrow slit length, so that the air amplifier can generate larger noise in a high-flow working state. There are also problems with the current commercial vaneless fans, including dyson: the noise is low when the fan runs at a low speed, but the air quantity and the air speed are lower than those of a common fan, so that the requirement of a user on large air quantity cannot be met; when the fan runs at a high speed, the air quantity and the air speed meet the demands of users, but the high-speed air flow at the narrow slit emits larger noise of the silk, and the use experience of the users is negatively affected to a certain extent.

Disclosure of Invention

The application provides an injection type air amplifier with a lobe nozzle, which aims to solve the technical problem that the existing common air amplifier is large in noise during working.

The technical scheme adopted by the application is as follows:

a lobe nozzle ejector air amplifier comprising: a gas collecting pipe for mounting and supporting and for introducing compressed air, and a plurality of lobe nozzles having lobe nozzles; the gas collecting tube is a hollow tube and is arranged in a ring shape, and an air inlet for compressed air to enter is formed in the gas collecting tube; the plurality of lobe nozzles are arranged in the inner ring of the gas collecting tube along Zhou Xiangyi times of the gas collecting tube at intervals, and the air inlet end of each lobe nozzle is communicated with the gas collecting tube, so that compressed air enters the lobe nozzle through the lobe nozzle and is sprayed outwards under the action of the lobe nozzle, and then ambient air in the external environment is ejected to enter the inner ring from the first side of the gas collecting tube and is mixed with compressed air flow formed by the injection of the lobe nozzle to form a mixed flow, and then is ejected outwards from the second side of the gas collecting tube.

Further, the gas collecting tube is arranged in a runway, and the gas inlet is arranged on the outer side wall of one short runway; the multiple lobe spray pipes are uniformly arranged at intervals along the length direction of the two long-distance runners.

Further, the gas collecting tube is arranged in a circular ring shape, and the gas inlet is arranged on the outer ring surface of the circular ring; the plurality of lobe nozzles are uniformly arranged at intervals along the circumference of the circular ring.

Further, the section of the gas collecting tube is an airfoil shape of an airplane wing; the lobe nozzles are connected to the inner annulus of the airfoil.

Further, the inner ring surface of the wing section is a suction surface with a gentle slope; the air inlet end of the lobe nozzle is communicated with the suction surface of the front edge of the airfoil, and the nozzle of the lobe nozzle faces the tail of the airfoil.

Further, the lobe nozzle further comprises an air inlet pipe for communicating the lobe nozzle with the gas collecting pipe; the gas collecting tube, the gas inlet tube and the lobe nozzle are integrally formed; or the gas collecting tube, the gas inlet tube and the lobe nozzle are respectively formed and fixedly connected in a welding and cementing mode.

Further, the lobe nozzle comprises a plurality of lobes formed by alternately arranging and connecting the wall surfaces of the lobe nozzle along the circumferential wave crests and the wave troughs; the gap between two wall surfaces of the wave crest forms an inner injection channel for injecting the compressed air in the lobe nozzle outwards; the gap between the two wall surfaces of the trough forms an external drainage channel for guiding the ambient air in the inner ring of the injection gas collecting tube.

Furthermore, semicircular gaps which occupy more than 2/3 of the lobe height are formed in the wall surfaces between the adjacent wave crests and wave troughs.

Further, the plurality of valleys form a central void around the center of the lobe nozzle; the lobe nozzle also comprises a central body for blocking the central cavity and a support plate for fixing the central body and the inner wall surface of the lobe.

Further, assuming that the maximum distribution diameter of the jet air flow of the lobe nozzle within the distance L from the outlet to the outlet side of the gas collecting tube is D, then: the distance between adjacent lobe nozzles is 60% -90% of D; the distance between the center of the lobe nozzle and the inner annular surface of the gas collecting ring is 30% -45% of D.

The application has the following beneficial effects:

as shown in fig. 12, CFD simulation and single nozzle test show that, under the same flow rate, the air flow amplification coefficient of the lobe nozzle injection type air amplifier is generally 22% higher than that of a common narrow slit nozzle, namely the air flow amplification effect of the lobe nozzle injection type air amplifier is better; it was also found by experiment that: because the inner compressed air flow sprayed by the lobe nozzle is mixed with the outer air flow sprayed by the outside for a short distance, the speed difference of the two air flows is small, and thus, the noise of the lobe nozzle is obviously smaller than that of the narrow slit nozzle under the same maximum nozzle flow velocity, and the advantage can also be proved by the application effect of the lobe ejector on an aeroengine.

In addition to the objects, features and advantages described above, the present application has other objects, features and advantages. The present application will be described in further detail with reference to the drawings.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the application. In the drawings:

FIG. 1 is a schematic diagram of a prior art air amplifier;

FIG. 2 is a diagram of a Dyson vaneless fan patent application;

FIG. 3 is a schematic diagram of a front view of a lobe nozzle ejector air amplifier in accordance with a preferred embodiment of the present application;

FIG. 4 is a schematic left side view of the center section of FIG. 3;

FIG. 5 is a schematic diagram of a front view of a lobe nozzle ejector air amplifier according to a preferred embodiment of the application;

FIG. 6 is a three-dimensional side view of a lobe nozzle of a preferred embodiment of the application;

FIG. 7 is a transverse cross-sectional view of a lobe nozzle ejector air amplifier;

FIG. 8 is a cross-sectional view of a lobe nozzle;

FIG. 9 is a schematic illustration of the injection principle of a lobe nozzle;

FIG. 10 is a schematic view of the lobe nozzle airflow streamlines within the header at the region of greatest influence;

FIG. 11 is a lobe nozzle distribution position versus nozzle flow maximum impact area;

fig. 12 is a streamline simulation of a racetrack lobe nozzle.

Description of the drawings

1. A gas collecting tube; 101. an air inlet; 2. lobe nozzle; 20. an air inlet pipe; 30. a lobe nozzle; 301. an inner injection passage; 302. an external drainage channel; 31. lobes; 311. a peak; 312. a trough; 313. a wall surface; 314. a semicircular notch; 32. a central body; 33. and (5) supporting plates.

Detailed Description

Embodiments of the application are described in detail below with reference to the attached drawing figures, but the application can be practiced in a number of different ways, as defined and covered below.

Referring to fig. 3 and 5, a preferred embodiment of the present application provides a lobe nozzle ejector air amplifier comprising: a header 1 for the installation and support of the compressed air and a plurality of lobe nozzles 2 with lobe nozzles 30. The gas collecting tube 1 is a hollow tube and is arranged in a ring shape, and the gas collecting tube 1 is provided with a gas inlet 101 for compressed air to enter. The plurality of lobe nozzles 2 are arranged in the inner ring of the gas collecting tube 1 along Zhou Xiangyi times of the gas collecting tube 1 at intervals, and the air inlet end of each lobe nozzle 2 is communicated with the gas collecting tube 1, so that compressed air enters the lobe nozzle 30 through the lobe nozzles 2 and is sprayed outwards under the action of the lobe nozzle 30, and then ambient air in the external environment is ejected to enter the inner ring from the first side of the gas collecting tube 1 and is mixed with compressed air flow formed by spraying of the lobe nozzle 30 to form a mixed flow, and then is sprayed outwards from the second side of the gas collecting tube 1.

In the prior art, two air flows of a turbofan engine are generally provided, one air flow is a high Wen Nahan air flow discharged from a turbine, the other air flow is a low-temperature external air flow discharged from a turbofan, the two air flows of the turbofan engine with a large bypass ratio are generally discharged from an inner spray pipe and an outer spray pipe separately, and the air flows of the turbofan engine with a small bypass ratio are generally discharged from the same spray pipe after being mixed. The mixed and re-exhausted mode produces greater thrust and less noise than the separate exhaust mode. The mixer is a device for mixing inner and outer airflows in the turbofan engine, the common mixer consists of two concentric circular cylinders, a lobe mixer with better mixing efficiency is developed later, and the lobe mixer is a device for enhancing the homodromous mixing flow. The power device of the helicopter, namely the turboshaft engine, adopts a lobe-type spray pipe, and the purpose of the turboshaft engine is to strengthen the capability of the spray pipe for injecting air flow from the outside atmosphere, reduce the temperature of the air flow after the spray pipe, and reduce the infrared radiation intensity of the engine. Therefore, the lobe mixer has wide application in aeroengines, and can be used for improving thrust, reducing oil consumption, reducing noise, reducing infrared radiation and the like. In principle of a lobe mixer of an aviation turbofan engine, the application provides a lobe nozzle injection type air amplifier, when the aviation turbofan engine works, external compressed air firstly enters a gas collecting pipe 1 through an air inlet 101, then is dispersed into each lobe spray pipe 2 through the gas collecting pipe 1, finally is sprayed into an inner ring of the gas collecting pipe 1 through a lobe spray nozzle 30 of each lobe spray pipe 2, and meanwhile, compressed air formed by the spraying of the lobe spray nozzle 30 pulls ambient air in an external environment to enter the inner ring from a first side of the gas collecting pipe 1, and is mixed with the compressed air formed by the spraying of the lobe spray nozzle 30 to form a mixed flow, and then is sprayed outwards from a second side of the gas collecting pipe 1.

As shown in fig. 12, CFD simulation and single nozzle test show that, under the same flow rate, the air flow amplification coefficient of the lobe nozzle injection type air amplifier is generally 22% higher than that of a common narrow slit nozzle, namely the air flow amplification effect of the lobe nozzle injection type air amplifier is better; it was also found by experiment that: because the inner air stream ejected by the lobe nozzle 30 is mixed with the outer air stream ejected from the outside by a short distance, the velocity difference between the two air streams is small, and thus, the noise of the lobe nozzle 30 is obviously smaller than that of the narrow slit nozzle under the same maximum jet flow velocity, and the advantage can be demonstrated by the application effect of the lobe ejector on an aeroengine.

Alternatively, as shown in fig. 3, the gas collecting tube 1 is arranged in a track shape, and the gas inlet 101 is formed on the outer side wall of one of the short tracks. The plurality of lobe nozzles 2 are uniformly spaced along the length direction of the two long-distance runners. In operation, the header 1 is not only used to feed compressed air into each of the communicating lobe nozzles 2, but also to direct ambient air into the interior of the annulus of the header 1.

Alternatively, as shown in fig. 5, the gas collecting tube 1 is arranged in a circular ring shape, and the gas inlet 101 is arranged on the outer ring surface of the circular ring. The plurality of lobe nozzles 2 are uniformly spaced along the circumference of the ring. In operation, the header 1 is not only used to feed compressed air into each of the communicating lobe nozzles 2, but also to direct ambient air into the interior of the annulus of the header 1.

Preferably, as shown in fig. 4, the cross section of the header 1 is in the shape of an airfoil of an aircraft wing. The lobe nozzles 2 are connected to the inner annulus of the airfoil. When the air jet type wing jet type air jet device works, air in front of the wing profile enters the ring of the gas collecting tube 1 around the front edge of the wing profile and flows to the tail of the wing profile under the jet effect of jet air flow of the lobe nozzle 30, the section of the gas collecting tube 1 is the wing profile of the wing of the aircraft, and the jet effect of the wing profile can be effectively improved due to good pneumatic design. Of course, the section of the gas collecting tube 1 does not need to adopt an airfoil, and the injection effect is poorer than that of the airfoil.

Further, as shown in FIG. 4, the inner annulus of the airfoil is a suction surface having a relatively gentle slope. The inlet end of the lobe nozzle 2 communicates with the suction surface of the airfoil leading edge, and the nozzle orifice of the lobe nozzle 30 is directed toward the airfoil trailing portion. When the air jet type wing jet device works, air in front of the wing profile enters the ring of the gas collecting tube 1 around the front edge of the wing profile and flows to the tail of the wing profile under the jet effect of jet air flow of the lobe nozzle 30, the section of the gas collecting tube 1 is the wing profile of the wing of the aircraft, and the good aerodynamic design of the wing profile can prevent the air flow from being separated easily when the air flow flows along the suction surface of the wing profile, so that the jet effect is reduced, and the jet effect is further improved.

Optionally, as shown in fig. 6 and 7, the lobe nozzle 2 further comprises an air inlet pipe 20 communicating the lobe nozzle 30 with the header 1. The header 1, the inlet pipe 20 and the lobe nozzle 30 are integrally formed. Or the gas collecting tube 1, the gas inlet tube 20 and the lobe nozzle 30 are respectively formed and fixedly connected by welding and cementing. In this alternative, the gas collecting tube 1, the gas inlet tube 20 and the lobe nozzle 30 may be molded together by casting, 3D printing or injection molding, or may be connected together by welding or cementing after being molded separately.

Alternatively, as shown in fig. 6 and 7, the lobe nozzle 30 includes a plurality of lobes 31 formed by alternating and connected circumferential peaks 311, valleys 312 of its wall 313. The gap between the two walls 313 of the crest 311 forms an inner injection channel 301 for the compressed air in the lobe nozzle 2 to be injected outwards. The gap between the two walls 313 of the trough 312 forms an outer drainage channel 302 for guiding ambient air injected into the inner ring of the header 1. In the present application, as shown in fig. 6 and 7, the lobe nozzle 30 is essentially a convergent nozzle, but the conical wall surface of the common nozzle is replaced by the lobe nozzle 2 with innovative design, and in combination with fig. 9, the wave crests 311 and the wave troughs 312 in the lobe nozzle 30 are used for forcing and guiding two air flows of the inner air flow and the outer air flow to flow inwards and outwards in a cross manner, so that the mixing of the two air flows is accelerated, the mixing effect is improved, and the working noise is reduced.

In general, the smaller the gap between the lobes 31 of the lobe nozzle 30 and the larger the number of the lobes 31, the longer the length of the boundary line between the inner and outer air streams of the lobe nozzle 30, and the better the ejection effect, as shown in fig. 6, the lobe nozzle 30 having 8 lobes 31 has the length of the boundary line 3 times or more that of the slit nozzle, compared with the conventional straight line or circular arc-shaped slit nozzle having the same flow area, and thus the better the ejection effect.

Preferably, as shown in fig. 8, a semicircular notch 314 accounting for more than 2/3 of the height of the lobe 31 is further formed on the wall 313 between the adjacent peaks 311 and troughs 312. In the preferred embodiment, the semicircular notch 314 may be of other shapes, such as parabolic, to promote lateral mixing of the two streams of air on both the inner and outer sides of the wall 313 of the lobe 31 to enhance mixing.

Alternatively, as shown in FIG. 8, a plurality of valleys 312 form a central void around the center of the lobe nozzle 30. The lobe nozzle 30 further includes a central body 32 for blocking the central hollow, and a support plate 33 for fixing the central body 32 to the inner wall surface of the lobe 31. In this alternative, the central body 32 acts to block the central void formed by the plurality of valleys 312 about the center, forcing the air flow against the walls of the valleys 312, thereby enhancing the blending effect.

In the present application, the lobe nozzle 2 is essentially a convergent nozzle, without a divergent section, with a total inlet pressure of only a few hundred pascals greater than the external atmospheric pressure, and a maximum outlet flow rate of typically about 20 to 30 m/s. In the application, the main innovation point of the lobe nozzle 2 is that a common circular convergent nozzle is changed into a lobe nozzle, a central body 32 is additionally arranged in the center, so that air flow is prevented from flowing out of a central cavity surrounded by the trough 312, and the air flow is forced to follow the peaks 311 and the troughs 312 of the lobe 31; in addition, the wall 313 of the lobe 31 is provided with a large-sized semicircular notch 314, so that the length of the boundary line between the inner air flow and the outer air flow is increased, and compared with a nozzle only adopting a common lobe, the lobe nozzle 2 greatly improves the ejection effect.

In practical design, the air flow rate generated by a single nozzle orifice of the lobe nozzle 30 cannot meet the requirements of most application scenes, so that a plurality of lobe nozzles 30 are generally needed, the number of specific lobe nozzles 30 is determined according to the required air quantity, and the air flows between different lobe nozzles 30 can mutually enhance the ejection effect of each other by optimizing the distribution position of the lobe nozzles 30 in the runway-type or ring-type air collecting tube 1, so that the air flow amplification effect can be improved, and the air flow distribution at the outlet of the air amplifier can be uniform. When optimizing, assuming that the maximum distribution diameter of the jet air flow of the lobe nozzle 30 within the distance L from the outlet to the outlet side of the header 1 is D, then:

the spacing between adjacent lobe nozzles 30 is 60% to 90% of D.

The spacing between the center of the lobe nozzle 30 and the inner annular surface of the gas collecting ring is 30% -45% of D.

Optimization of the distribution position of the lobe nozzles 30 in the racetrack or annular header 1 can be performed as follows:

first, the maximum distribution diameter D of the outlet airflow of the nozzles 30 of the single lobe is determined by CFD simulation or experiment, as shown in fig. 10, over the distance L from the outlet to the outlet of the header 1;

then, by adjusting the distribution positions of the lobe nozzles 30 so that the distance between adjacent lobe nozzles 30 is 60% -90% of D, the distance between the center of the lobe nozzle 30 and the inner annular surface of the gas collecting ring is 30% -45% of D, as shown in fig. 11.

As shown in fig. 12, which shows the CFD simulation results (airflow patterns) of half of the racetrack-type lobed nozzle ejector amplifier shown in fig. 3 with 10 lobed nozzles 30, each streamline is almost straight from front to back, with no obvious sign of swirl; meanwhile, although the flow rate of the air flow gradually decreases with increasing distance, the flow rate is substantially uniform over the cross section of each fixed distance, thereby indicating that the method provides an air flow of good quality.

In the application, a plurality of lobe nozzles 30 are positioned in the inside of a runway-type or circular-ring-shaped gas collecting tube 1, and the distances between the lobe nozzles 30 and the inner circular surface of the gas collecting tube 1 are controlled to be smaller than the diameter of the maximum distribution circle which can be achieved by the outlet airflow streamline of the lobe nozzle 2 in the length of the gas collecting tube 1, so that the airflows of different lobe nozzles 30 can enhance the ejection effect of each other, and the ejection enhancement effect of multiple-nozzle airflows does not exist in a single nozzle.

The above description is only of the preferred embodiments of the present application and is not intended to limit the present application, but various modifications and variations can be made to the present application by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A lobe nozzle ejector air amplifier comprising:

a gas collecting tube (1) which is used for installing and supporting and is used for introducing compressed air, and a plurality of lobe nozzles (2) with lobe nozzles (30);

the gas collecting tube (1) is a hollow tube and is arranged in a ring shape, and the gas collecting tube (1) is provided with a gas inlet (101) for compressed air to enter;

the plurality of lobe nozzles (2) are arranged in the inner ring of the gas collecting tube (1) along Zhou Xiangyi times of the gas collecting tube (1) at intervals, and the air inlet end of each lobe nozzle (2) is communicated with the gas collecting tube (1) so that compressed air enters the lobe nozzle (30) through the lobe nozzles (2) and is sprayed outwards under the action of the lobe nozzle (30), and then ambient air in the external environment is ejected to enter the inner ring from the first side of the gas collecting tube (1) and is mixed with compressed air flow formed by spraying of the lobe nozzle (30) to form a mixed flow, and then is sprayed outwards from the second side of the gas collecting tube (1).

2. The lobed nozzle ejector air amplifier of claim 1,

the gas collecting tube (1) is arranged in a runway, and the gas inlet (101) is arranged on the outer side wall of one short runway;

the lobe spray pipes (2) are uniformly arranged at intervals along the length direction of the two long-distance runners.

3. The lobed nozzle ejector air amplifier of claim 1,

the gas collecting tube (1) is arranged in a circular ring shape, and the gas inlet (101) is arranged on the outer ring surface of the circular ring;

the plurality of lobe nozzles (2) are uniformly arranged at intervals along the circumferential direction of the circular ring.

4. The lobed nozzle ejector air amplifier of claim 1,

the section of the gas collecting tube (1) is an airfoil shape of an airplane wing;

the lobe nozzle (2) is connected to the inner ring surface of the wing section.

5. The lobed nozzle ejector air amplifier of claim 4,

the inner ring surface of the wing section is a suction surface with a relatively slow gradient;

the air inlet end of the lobe nozzle (2) is communicated with the suction surface of the front edge of the airfoil, and the nozzle opening of the lobe nozzle (30) faces the tail of the airfoil.

6. The lobed nozzle ejector air amplifier of claim 1,

the lobe nozzle (2) also comprises an air inlet pipe (20) for communicating the lobe nozzle (30) with the gas collecting pipe (1);

the gas collecting tube (1), the gas inlet tube (20) and the lobe nozzle (30) are integrally formed; or alternatively

The gas collecting tube (1), the gas inlet tube (20) and the lobe nozzle (30) are respectively formed and fixedly connected in a welding and cementing mode.

7. The lobed nozzle ejector air amplifier of claim 1,

the lobe nozzle (30) comprises a plurality of lobes (31) formed by alternately arranging and connecting the wall surfaces (313) of the lobe nozzle along circumferential wave crests (311) and wave troughs (312);

the gap between the two wall surfaces (313) of the wave crest (311) forms an inner injection channel (301) for injecting the compressed air in the lobe nozzle (2) outwards;

the gap between the two wall surfaces (313) of the trough (312) forms an external drainage channel (302) for guiding the ambient air in the inner ring of the injection gas collecting tube (1).

8. The lobed nozzle ejector air amplifier of claim 7,

semi-circular notches (314) accounting for more than 2/3 of the height of the lobe (31) are also arranged on the wall surface (313) between the adjacent wave crests (311) and wave troughs (312).

9. The lobed nozzle ejector air amplifier of claim 7,

a plurality of valleys (312) form a central void around the center of the lobe nozzle (30);

the lobe nozzle (30) further comprises a central body (32) for blocking the central cavity, and a support plate (33) for fixing the central body (32) and the inner wall surface of the lobe (31).

10. The lobed nozzle ejector air amplifier of claim 1,

assuming that the maximum distribution diameter of the jet air flow of the lobe nozzle (30) within the distance L from the outlet to the outlet side of the gas collecting tube (1) is D:

the spacing between adjacent lobe nozzles (30) is 60% -90% of D;

the distance between the center of the lobe nozzle (30) and the inner annular surface of the gas collecting ring is 30% -45% of D.