Ejector, auxiliary power unit for aircraft, and aircraft

Abstract

The present invention provides an ejector, an auxiliary power unit for an aircraft, and an aircraft, wherein the ejector includes a main spray unit, a bleed unit, a cooling unit, an ejector unit, and a mixing section; wherein the main spray unit, the ejector unit, and the mixing section are connected in sequence, the cooling unit is connected to the ejector unit, the bleed unit is connected to the ejector unit, and the mixing section is located at the most downstream part of the fluid passage; furthermore, the main airflow from the main spray unit, the cooling airflow from the cooling unit, and the bleed airflow from the bleed unit are mixed together and discharged through the mixing section. The present invention can make good use of the bleed gas energy, while significantly improving the uniformity of the flow field inside the ejector, thereby improving the ejection capacity and strength life of the ejector.

Description

Technical Field

[0001] The present invention belongs to the technical field of aviation ejectors, and in particular relates to an ejector, an auxiliary power unit for an aircraft, and an aircraft. Background Art

[0002] The auxiliary power unit is an onboard device of modern large civil passenger aircraft. It mainly provides auxiliary / emergency power or air source for the aircraft and is usually installed in the auxiliary power compartment at the tail of the aircraft.

[0003] The exhaust ejector is one of the components in the auxiliary power unit. Its main function is to provide ventilation cooling and oil heat dissipation in the auxiliary power compartment. It is usually installed on the exhaust frame at the tail of the auxiliary power unit.

[0004] The main working principle of the exhaust ejector is to use the high-speed airflow discharged from the tail nozzle of the auxiliary power unit to eject the low-temperature gas from the air inlet into the auxiliary power compartment. After the low-temperature gas flows through the auxiliary power compartment, it enters the oil radiator installed at the inlet of the ejector to dissipate the heat of the oil. Finally, it flows through the ejector, mixes with the high-temperature airflow from the tail nozzle, and is discharged outside the aircraft through the aircraft exhaust pipe.

[0005] During the operation of the auxiliary power unit, in order to improve the surge margin of the compressor, a certain proportion of airflow is usually drawn out from the compressor, introduced into the aircraft exhaust pipe through a duct, and discharged out of the aircraft along with the exhaust pipe. This part of the gas energy is not effectively utilized, and if the design is unreasonable, it will greatly affect the performance of the exhaust ejector.

[0006] Since the existing auxiliary power unit bleed air flow is usually introduced directly into the auxiliary power unit exhaust pipe through a conduit, this design fails to effectively utilize this part of the gas flow, and on the other hand will greatly reduce the uniformity of the flow field inside the ejector. Since both the main jet and the bleed air flow are high-temperature gases, the uneven gas flow will greatly reduce the ejection performance and strength life of the ejector. Summary of the Invention

[0007] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides an aviation ejector, in particular an exhaust ejector for an auxiliary power unit of an aircraft, which is conducive to improving the ejection capacity, strength and life of the ejector.

[0008] To achieve the above-mentioned purpose, the present invention provides an ejector, comprising a main spray unit, a bleed unit, a cooling unit, an ejector unit and a mixing section; wherein, the main spray unit, the ejector unit and the mixing section are connected in sequence, the cooling unit is connected to the ejector unit, the bleed unit is connected to the ejector unit, and the mixing section is located at the most downstream part of the fluid passage; further, the main airflow from the main spray unit, the cooling airflow from the cooling unit and the bleed airflow from the bleed unit are mixed together and discharged through the mixing section.

[0009] Furthermore, the degassing unit includes a first degassing component for introducing gas and a second degassing component for making the gas flow uniform, the first degassing component is connected to the second degassing component, and the first degassing component is located upstream of the second degassing component.

[0010] Furthermore, a plurality of jet holes are evenly arranged circumferentially at the outlet of the second air releasing component.

[0011] Furthermore, the second air releasing component is adjacent to the ejection unit, and the second air releasing component is located in front of or behind the ejection unit.

[0012] Furthermore, the second air releasing component is annular or volute-shaped.

[0013] Furthermore, the flow channel area of the second air-releasing component continuously decreases, and the farther away from the outlet of the first air-releasing component, the smaller the flow channel area.

[0014] Furthermore, the ejection unit is annular or volute-shaped.

[0015] Furthermore, the apertures of the plurality of jet holes increase with increasing distance from the first air release component, and the farther away from the outlet of the first air release component, the larger the aperture of the jet hole; wherein the aperture range of the jet hole is

[0016] An auxiliary power unit for an aircraft, comprising the ejector described above.

[0017] An aircraft comprising the above-mentioned aircraft auxiliary power unit, or comprising the above-mentioned ejector.

[0018] Compared with the prior art, the advantages of the present invention are:

[0019] (1) The aviation ejector of the present invention effectively utilizes the gas flow of the auxiliary power unit's bleed airflow. By providing a heat sink to introduce cooling airflow, the uneven airflow caused by both the main jet and bleed airflow being high-temperature gases is overcome, resulting in a more uniform airflow.

[0020] (2) The internal airflow channel area of the second air release component of the present invention is variable, and the channel area decreases continuously along the airflow direction, ensuring that the air release airflow enters the ejection unit more evenly.

[0021] (3) The jet holes of the present invention are arranged roughly in a ring shape. The apertures of the jet holes are not exactly the same. The apertures increase with the increase of the distance from the deflation duct, further ensuring the uniformity of the deflation airflow.

[0022] (4) The second air release component and the ejection unit of the present invention are roughly shaped like a hollow ring or a volute, which further makes the airflow more uniform.

[0023] (5) The present invention can make good use of the energy of the deflated gas and significantly improve the uniformity of the flow field inside the ejector, thereby improving the ejection capacity and strength life of the ejector.

[0024] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 A schematic diagram of an aerial ejector in accordance with a first embodiment of the present invention is shown;

[0027] Figure 2 A three-dimensional model diagram of an aerial ejector in a first embodiment of the present invention is shown;

[0028] Figure 3 A schematic diagram of the degassing unit of the present invention is shown;

[0029] Figure 4 A schematic diagram showing another angle of the degassing unit of the present invention is shown;

[0030] Figure 5 A schematic diagram of an aerial ejector according to a second embodiment of the present invention is shown;

[0031] Figure 6 A three-dimensional model diagram of an aviation ejector in a second embodiment of the present invention is shown.

[0032] In the figure, 1-main nozzle, 2-bleeding duct, 3-bleeding volute, 4-radiator, 5-injection volute, 6-mixing section, 7-jet hole. DETAILED DESCRIPTION

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0034] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0035] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0036] The first embodiment of the present invention is shown in FIG. Figures 1-4 The first embodiment of the present invention relates to an aircraft ejector, particularly an exhaust ejector for an auxiliary power system of an aircraft, comprising a main ejector unit, a bleed unit, a cooling unit, an ejector unit, and a mixing section 6. The bleed unit includes a first bleed component for introducing gas and a second bleed component for uniforming the air flow. The main ejector unit, the bleed unit, and the ejector unit are all fluidically connected to the mixing section 6, which is located at the downstream end of the fluid pathway.

[0037] The main spray unit is connected to one side of the ejection unit by welding or bolts; the other side of the ejection unit is connected to the mixing section 6 by welding or bolts; a venting unit is provided on the outer periphery of the main spray unit, and the venting unit is connected to one side of the ejection unit by welding or bolts; the cooling unit is arranged at the inlet of the ejection unit by bolts.

[0038] The first air release component and the second air release component are connected by welding, and the first air release component is located upstream of the second air release component. In some embodiments, the air release unit can be manufactured using an integrated molding technology.

[0039] The second air releasing component is in an annular shape or a volute shape.

[0040] The ejection unit is annular or volute-shaped.

[0041] The main spray unit is specifically a main nozzle 1, the first air release component is specifically a air release duct 2, the second air release component is specifically a air release volute 3, the cooling unit is specifically a radiator 4, and the ejection unit is specifically an ejection volute 5. The air release volute 3 is adjacent to the ejection volute 5 and is located in front of the ejection volute 5.

[0042] like Figure 1-Figure 2 As shown, the high-temperature combustion gas from the auxiliary power unit enters the ejector through the main nozzle 1, and the cooling airflow within the auxiliary power compartment enters the ejector through the radiator 4. The bleed volute 3 is arranged in front of the ejector volute 5. The bleed airflow from the auxiliary power unit body enters the annular bleed volute 3 through the bleed duct 2. Several jet holes 7 are evenly distributed around the circumference of the outlet of the bleed volute 3. The bleed airflow enters the ejector volute 5 through these jet holes 7. Finally, the main airflow (from the main nozzle 1), the cooling airflow, and the bleed airflow are mixed together and discharged outside the machine through the mixing section 6. On the one hand, for the bleed airflow of the auxiliary power unit, especially the airflow discharged from the compressor, introducing this part of the bleed airflow into the ejector effectively utilizes this part of the gas energy. On the other hand, introducing the cooling gas into the ejector reduces the overall temperature of the mixed airflow, making the airflow more uniform, thereby improving the ejection capacity and strength life of the ejector.

[0043] like Figure 3-Figure 4 As shown, the outer shape of the deflation volute 3 can be changed according to the external constraints. Figure 3 As shown, in order to ensure that the deflated airflow enters the ejector volute 5 more evenly, the internal airflow passage area of the deflated volute 3 is variable, and the cross section is trapezoidal. For example, the flow passage area decreases continuously along the airflow direction, and the farther away from the outlet of the deflated duct 2, the smaller the flow passage area. Figure 4As shown, in order to ensure that the deflated airflow enters the ejector volute 5 more evenly, the apertures of all the jet holes 7 are not exactly the same. For example, multiple jet holes 7 are evenly arranged in a roughly circular shape at the outlet of the deflated volute 3. The aperture increases with the increase of the distance from the deflated duct 2. The farther from the outlet of the deflated duct 2, the larger the aperture of the jet hole 7. The aperture range of the jet hole 7 is To ensure a more even flow of deflated air into the ejector volute 5, the number, distribution, and diameter of the jet holes 7 can be adjusted. To ensure the lifespan and reliability of the radiator 4, the distance between the jet holes 7 and the radiator 4 can be adjusted, ranging from 200mm to 400mm. The design of the deflated volute 3 and ejector volute 5 achieves a more even flow, thereby improving the ejector's ejection capacity, strength, and lifespan.

[0044] The second embodiment of the present invention is shown in FIG. Figure 5-Figure 6 High-temperature combustion gas from the auxiliary power unit enters the ejector volute 5 through the main nozzle 1, while cooling air from the auxiliary power compartment enters the ejector volute 5 through the radiator 4. The bleed volute 3 is adjacent to and positioned behind the ejector volute 5. Bleed air from the auxiliary power unit enters the annular bleed volute 3 through the bleed duct 2. Several jet holes 7 are formed at the outlet of the bleed volute 3, through which the bleed air enters the mixing section 6. Ultimately, the main airflow, cooling airflow, and bleed air flow are mixed and discharged through the mixing section 6. All other details not described in detail in the second embodiment are the same as or symmetrical to those of the first embodiment.

[0045] Based on the ejector described in the first or second embodiment of the present invention, the present invention further provides a method for uniform ejector airflow, wherein the ejector comprises a main spray unit, a bleed unit, a cooling unit, an ejector unit, and a mixing section 6; the main spray unit, the bleed unit, and the ejector unit are all fluidically connected to the mixing section 6, and the mixing section 6 is located at the most downstream portion of the fluid passage;

[0046] The method comprises: mixing the main airflow from the main spray unit, the cooling airflow from the cooling unit and the bleed airflow from the bleed unit and discharging the mixed airflow through the mixing section 6;

[0047] Furthermore, the temperature of the mixed airflow is lowered by the cooling airflow.

[0048] Furthermore, by allowing the air flow to pass through the air release unit, the flow of the air flow becomes uniform.

[0049] The present invention also provides an auxiliary power unit for an aircraft, wherein the auxiliary power unit for an aircraft includes the ejector described in any one of the above items.

[0050] The present invention also provides an aircraft, wherein the aircraft includes the auxiliary power unit for aircraft as described above, or includes the ejector as described in any one of the above items.

[0051] Because existing auxiliary power unit bleed air is typically introduced directly into the auxiliary power unit exhaust pipe through a conduit, this design not only fails to effectively utilize this portion of gas flow, but also significantly reduces the uniformity of the flow field within the ejector. Because both the main jet and bleed air flows are high-temperature gases, the uneven gas flow significantly reduces the ejection performance and strength life of the ejector. The present invention effectively utilizes the bleed gas energy while significantly improving the flow field uniformity within the ejector, thereby enhancing the ejection capacity and strength life of the ejector.

[0052] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An ejector, characterized in that: The invention comprises a main spray unit, a bleed unit, a cooling unit, an ejection unit and a mixing section (6); wherein the main spray unit, the ejection unit and the mixing section (6) are connected in sequence, the cooling unit is connected to the ejection unit, the bleed unit is connected to the ejection unit, and the mixing section (6) is located at the most downstream of the fluid passage; furthermore, the main airflow from the main spray unit, the cooling airflow from the cooling unit and the bleed airflow from the bleed unit are mixed together and discharged through the mixing section (6); The degassing unit includes a first degassing component for introducing gas and a second degassing component for making the gas flow uniform, the first degassing component is connected to the second degassing component, and the first degassing component is located upstream of the second degassing component; The flow channel area of the second air release component decreases continuously, and the farther away from the outlet of the first air release component, the smaller the flow channel area.

2. The ejector according to claim 1, characterized in that A plurality of jet holes (7) are evenly arranged in the circumferential direction at the outlet of the second air release component.

3. The ejector according to claim 1, characterized in that The second air releasing component is adjacent to the ejection unit, and the second air releasing component is located in front of or behind the ejection unit.

4. The ejector according to claim 1, characterized in that The second air releasing component is in a ring shape or a volute shape.

5. The ejector according to claim 1, characterized in that The ejection unit is in a ring shape or a volute shape.

6. The ejector according to claim 2, characterized in that The apertures of the plurality of jet holes (7) increase as the distance from the first air release component increases. The farther away from the outlet of the first air release component, the larger the aperture of the jet hole (7). The aperture range of the jet hole (7) is .

7. An auxiliary power unit for an aircraft, characterized in that: The auxiliary power unit for an aircraft includes the ejector according to any one of claims 1 to 6.

8. An aircraft, characterized in that: The aircraft comprises the auxiliary power unit for aircraft as claimed in claim 7 , or comprises the ejector as claimed in any one of claims 1 to 6 .

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