Aircraft engine fan air inlet structure and aircraft comprising same

Abstract

An air inlet structure of an aircraft engine fan is used for introducing air flow in an outer duct of an engine into a downstream air source system, and comprises a first air inlet, a second air inlet, an air outlet, an air outlet, a flow guide device and an air outlet, and the first air inlet and the second air inlet are arranged on the surface of a rectifying device in the outer duct of the engine; a first inlet passage communicating with the first intake inlet and extending downstream from the first intake inlet; a second inlet passage communicating with the second intake inlet and extending downstream from the second intake inlet; and a main inlet passage in direct communication with both the first and second inlet passages downstream of the first and second inlet passages, and configured such that the first intake inlet can communicate with the second intake inlet sequentially via the first inlet passage, the main inlet passage, and the second inlet passage. The structure is favorable for eliminating pressure fluctuation in a fan air inlet system, reduces the influence on an external duct flow field on the premise of ensuring the self efficiency, and is easy to produce, process and mount.

Description

Technical Field

[0001] The present invention relates to the field of aircraft design and manufacture, and more specifically to the field of aircraft engine design and manufacture, and in particular to an aircraft engine fan air intake inlet structure and an aircraft comprising the aircraft engine fan air intake inlet structure. Background Art

[0002] In aircraft systems, especially civil aircraft systems, in addition to providing propulsion for the aircraft, the engine also needs to provide air source for the aircraft air source system for downstream air-using systems, including but not limited to air conditioning systems, anti-icing systems, etc.

[0003] Generally, since the high-temperature and high-pressure gas is drawn out from the engine compressor, it is usually necessary to use a heat exchanger to cool this part of the high-temperature and high-pressure gas by introducing low-temperature gas from the engine duct to meet the requirements of the gas source system. The gas in the cold side channel of the heat exchanger can generally be introduced from the fan air inlet (Scoop) at a lateral inclination relative to the mainstream direction of the duct, enter the heat exchanger after flowing through the fan air valve downstream of the fan air inlet, and be discharged outside the engine after completing the heat exchange.

[0004] The air source system of an aircraft has different flow requirements for the cold side of the heat exchanger under different flight conditions. For example, under certain working conditions, the air source system has a zero flow requirement for the cold side of the heat exchanger, and at this time, the above-mentioned fan air valve is closed. In this state, the fan air inlet becomes a relatively short and thick closed cavity connected to the engine external duct fairing device (BIFI). Taking into account the specific flow field environment of the engine external duct, that is, the general flow rate is around Mach number 0.6, as the airflow in the external duct flows along the flow direction through the outside of the fan air inlet, the closed cavity will produce huge pressure fluctuations. This phenomenon not only generates huge noise, but also brings about huge safety hazards to the aircraft air source system due to the vibration, which has an impact on the safety and comfort of the aircraft that cannot be ignored.

[0005] In existing aircraft systems, in order to avoid the pressure fluctuation problem caused by the above reasons, it is usually solved by flow control methods such as increasing the length of the fan air inlet, adding guide vanes or adding bypass branches.

[0006] However, these solutions often increase the volume of the fan air inlet components or significantly reduce the aerodynamic performance of the engine or the fan air inlet.

[0007] CN207658077U, CN207740246U and CN107893778A propose fan air inlet devices with semi-covered baffles of different structures. Such solutions can effectively solve the pressure fluctuation problem, but have a great impact on the flow field of the engine outer duct and significantly increase the engine fuel consumption.

[0008] US20100126182A1 and US8024935B2 disclose a technical solution of adding a small blade at the air inlet of the fan air inlet device. This solution solves the pressure fluctuation problem by splitting the incoming airflow and forming a trail mixing area downstream of the guide vane. EP0926064B1 also adopts a similar idea to solve the pressure fluctuation problem. However, such a solution will lead to a significant decrease in the aerodynamic performance of the cold channel.

[0009] CN110439692A discloses a fan air inlet solution including an airflow branch structure. This solution can prevent the fan air inlet from becoming a closed cavity structure when the valve is closed. However, when the aircraft air source system is working normally, the branch structure will significantly reduce the heat exchanger cold channel flow, resulting in insufficient heat exchanger capacity, which will bring new hidden dangers to the aircraft air source system. In addition, the components designed according to this solution are not easy to process and install. Summary of the invention

[0010] The present invention is based on the deficiencies of the current technical solutions and takes into account the need to minimize the negative impact on the flow field in the engine outer duct and the channel under the premise of ensuring the elimination of the pressure fluctuation problem.

[0011] To this end, an aircraft engine fan air inlet structure is provided, wherein the aircraft engine fan air inlet structure is used to introduce the airflow in the engine outer duct into the downstream air source system.

[0012] in,

[0013] The aircraft engine fan air inlet structure comprises:

[0014] A first air intake inlet and a second air intake inlet are arranged on the surface of the fairing device in the engine outer duct;

[0015] a first inlet passage, the first inlet passage being in communication with the first air inlet and extending downstream from the first air inlet;

[0016] a second inlet passage communicating with the second air intake inlet and extending downstream from the second air intake inlet; and

[0017] A main inlet channel, wherein the main inlet channel is directly connected to both the first inlet channel and the second inlet channel downstream of the first inlet channel and the second inlet channel, wherein the main inlet channel is configured so that the first air intake can be connected to the second air intake via the first inlet channel, the main inlet channel and the second inlet channel in sequence.

[0018] Through two different air inlet inlets and corresponding inlet channels, the airflow entering the main inlet channel when the downstream valve is closed can flow out through the secondary inlet channel, which is beneficial to eliminate the pressure fluctuation problem in the fan intake system, and minimizes the impact on the external duct flow field while ensuring its own efficiency. It is also easy to produce, process and install.

[0019] According to a preferred embodiment of the aircraft engine fan air inlet structure of the present invention, the first air inlet is located upstream of the second air inlet in the flow direction of the airflow in the engine duct.

[0020] According to a preferred embodiment of the aircraft engine fan air intake inlet structure of the present invention, the first inlet channel and the second inlet channel are arranged so that, when the main inlet channel downstream is unobstructed, the aerodynamic resistance of the airflow flowing from the first inlet channel via the main inlet channel to the downstream is less than the aerodynamic resistance of the airflow flowing from the first inlet channel via the main inlet channel to the second inlet channel.

[0021] According to a preferred embodiment of the aircraft engine fan air intake inlet structure of the present invention, the first inlet passage and the second inlet passage extend downstream in substantially the same direction relative to the airflow in the engine duct.

[0022] According to a preferred embodiment of the aircraft engine fan air inlet structure of the present invention, the first air inlet and the second air inlet are substantially rectangular inlet openings.

[0023] According to a preferred embodiment of the aircraft engine fan air intake structure of the present invention, the long side of the rectangle is arranged substantially perpendicular to the flow direction of the airflow in the engine duct.

[0024] According to a preferred embodiment of the aircraft engine fan air inlet structure of the present invention, the ratio of the area of ​​the first air inlet to the area of ​​the second air inlet is between 2:1 and 5:1.

[0025] According to a preferred embodiment of the aircraft engine fan air intake inlet structure of the present invention, the flow cross-sectional area of ​​the first inlet passage gradually decreases along the flow direction starting from the first air intake inlet, and the flow cross-sectional area of ​​the second inlet passage gradually increases along the flow direction starting from the second air intake inlet.

[0026] According to a preferred embodiment of the aircraft engine fan air intake inlet structure of the present invention, the first inlet passage maintains a flow cross-sectional shape similar to that of the first air intake inlet.

[0027] and / or

[0028] The second inlet passage maintains a flow cross-sectional shape similar to that of the second intake inlet.

[0029] In addition, the present invention also relates to an aircraft, comprising:

[0030] The aircraft engine fan air inlet structure according to the foregoing content; and

[0031] A downstream air source system is located downstream of the aircraft engine fan air intake structure.

[0032] In summary, the technical advantages of various preferred embodiments of the aircraft engine fan air intake structure according to the present invention are at least:

[0033] 1) Eliminate the pressure fluctuation problem in the fan intake system, minimize the impact on the external duct flow field while ensuring its own efficiency, and be easy to produce, process and install.

[0034] 2) As a solution for single-side air intake from the engine's external duct fairing device, this solution can solve the problem of pressure fluctuation when the fan air valve is closed while ensuring the relative efficiency of the fan air inlet section.

[0035] 3) This solution does not make any geometric changes to the flow path of the engine duct, ensuring that the engine thrust and aircraft fuel efficiency are not affected.

[0036] 4) This solution is relatively simple to process and install, and increases the design redundancy of the aircraft. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] This document includes the accompanying drawings to provide a further understanding of the various embodiments, and the accompanying drawings are incorporated in and constitute a part of this specification.

[0038] The drawings illustrate the various embodiments described herein, and together with the description serve to explain the principles and operations of the claimed subject matter.

[0039] With reference to the above objects, the technical features of the present invention are clearly described hereinafter, and advantages thereof are apparent from the following detailed description with reference to the accompanying drawings, which illustrate preferred embodiments of the present invention by way of example without limiting the scope of the present invention.

[0040] In the attached figure:

[0041] Figure 1 It is a schematic three-dimensional diagram of a preferred embodiment of an aircraft engine fan air intake structure according to the present invention.

[0042] Figure 2 The preferred embodiment of the aircraft engine fan air intake structure according to the present invention is along Figure 1A schematic top view in a roughly horizontal direction.

[0043] Figure 3 It is a schematic diagram of the internal flow field of a preferred embodiment of the aircraft engine fan air intake structure according to the present invention when the downstream valve is opened.

[0044] Figure 4 It is a schematic diagram of the internal flow field of a preferred embodiment of the aircraft engine fan air intake structure according to the present invention when the downstream valve is closed.

[0045] Reference numerals list

[0046] 110 First Entrance

[0047] 111 First air intake

[0048] 120 Second Entrance

[0049] 121 Second air intake

[0050] 130 Main Entrance Passage

[0051] 200 Airflow in the engine duct

[0052] 300 Rectifier

[0053] A Flow direction DETAILED DESCRIPTION

[0054] Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings and described below.

[0055] Although the present invention will be described in conjunction with exemplary embodiments, it should be appreciated that this specification is not intended to limit the present invention to those exemplified embodiments. On the contrary, the present invention is intended to cover not only these exemplary embodiments, but also various alternative forms, modifications, equivalent forms and other embodiments that may be included within the spirit and scope of the present invention.

[0056] To facilitate explanation and accurately define the technical solutions of the present invention, the terms “upper”, “lower”, “inner” and “outer” are used to describe features of the exemplary embodiments shown in the drawings with reference to their positions.

[0057] Various preferred but non-limiting embodiments of the aircraft engine fan air intake structure of the present invention will be described in detail below with reference to the accompanying drawings.

[0058] like Figure 1 and Figure 2As shown in the figure, an aircraft engine fan air intake structure according to a preferred embodiment of the present invention is shown. The aircraft engine fan air intake structure is used to introduce the airflow 200 in the engine outer duct into the downstream air source system. It is conceivable that the aircraft may include the aircraft engine fan air intake structure shown in the figure and a downstream air source system located downstream of the aircraft engine fan air intake structure, including but not limited to an air source system for an air conditioning system, an anti-icing system, etc.

[0059] The aircraft engine fan air inlet structure comprises: a first air inlet 111 and a second air inlet 121 , a first inlet passage 110 and a second inlet passage 120 , and a main inlet passage 130 .

[0060] The first air inlet 111 and the second air inlet 121 are arranged on the surface of the fairing device 300 in the engine outer duct. It should be pointed out that the first air inlet 111 and the second air inlet 121 in this article should be understood as two independent air inlets, so that two separate air flow channels can be formed downstream of the relevant air inlet.

[0061] The arrangement position of the aircraft engine fan air intake structure in the engine duct according to the present invention, that is, the arrangement position of the fairing thrust reverser device in the engine duct, can be located at any position on the circumferential inner side of the engine, including but not limited to the arrangement position which can be the 12 o'clock position in the circumferential direction when the aircraft is on the ground, that is, the arrangement position above the engine turbine rotor near the top of the engine duct.

[0062] It should also be pointed out that in operation, Figure 1 The air inlet structure shown in FIG. 1 actually has an external mainstream flow on both the near side close to the paper and the far side far away from the paper. Figure 1 It is shown that the air inlets 111 and 121 are opened only toward the proximal side, but those skilled in the art will understand that, on the one hand, one or more air inlets may be opened toward the distal side in addition or alternatively, and on the other hand, in the case where the air inlet is opened only toward the proximal side, generally, the engine can be constructed so that the fluid mechanics characteristics of the proximal outer mainstream are more in line with the downstream air bleed requirements.

[0063] In a preferred embodiment, the first air intake inlet 111 may be located upstream of the second air intake inlet 121 in the flow direction A of the airflow 200 in the engine duct. Figure 1 and Figure 2 As shown by arrow A in Figure 1 In the embodiment, the first air inlet 111 is located on the right side of the second air inlet 121. Figure 2 In the embodiment, the first air inlet and its corresponding first inlet channel 110 are located on the left side of the second air inlet and its corresponding second inlet channel 120 .

[0064] In a preferred embodiment, and if Figure 1 As shown in the figure, the first air inlet 111 and the second air inlet 121 are substantially rectangular inlet openings. More preferably, the first air inlet 111 and the second air inlet 121 may be rectangular openings with one or more corners chamfered or rounded. In a preferred embodiment of such rectangular inlet openings, further preferably, the long side of the rectangle may be arranged substantially perpendicular to the flow direction A of the airflow 200 in the engine duct, that is, in Figure 1 It should be pointed out here that although Figure 1 The long sides of the rectangle in the figure are generally straight lines, but those skilled in the art will appreciate that, depending on the different profiles of the rectifier, the long sides of the rectangle may also be curves.

[0065] In a preferred embodiment, the area of ​​the first air inlet 111 may be larger than the area of ​​the second air inlet 121. Preferably, the ratio of the area of ​​the first air inlet 111 to the area of ​​the second air inlet 121 may be between 2:1 and 5:1, and more preferably between 3:1 and 4:1. As for the specific shapes and sizes of the first air inlet 111 and the second air inlet 121, those skilled in the art may refer to the geometric parameters of the external duct rectifier and the design parameters of the cold side of the air source system heat exchanger to determine, which will not be repeated here. Figure 1 As shown in , the above-mentioned area difference can preferably be achieved by a size difference in the direction of the short side of the rectangle, while keeping the long sides of the rectangle in the vertical direction substantially equal in length.

[0066] Continue to refer Figure 1 and Figure 2 The first inlet passage 110 is in communication with the first air intake inlet 111 and extends downstream from the first air intake inlet 111. Similarly, the second inlet passage 120 is in communication with the second air intake inlet 121 and extends downstream from the second air intake inlet 121.

[0067] According to the concept of the present invention, the main inlet channel 130 is directly connected to both the first inlet channel 110 and the second inlet channel 120 downstream of the first inlet channel 110 and the second inlet channel 120, wherein, crucially, the main inlet channel 130 is configured so that the first air intake inlet 111 can be connected to the second air intake inlet 121 via the first inlet channel 110, the main inlet channel 130 and the second inlet channel 120 in sequence. Preferably, in the process of the first inlet channel 110 and the second inlet channel 120 merging, it can be configured to ensure a smooth transition of the airflow angle and the flow channel.

[0068] It is conceivable that the main inlet channel 130 is provided with an outlet of the engine fan air inlet structure of the present invention at the downstream, and therefore, the engine fan air inlet structure of the present invention can be understood as a channel section between the inlet and the outlet. Preferably, the length of the first inlet channel 110 and the second inlet channel 120 can account for about 50%-75% of the total length of the channel section of the entire engine fan air inlet structure, for example, about 55%-70% of the total length.

[0069] The first inlet channel 110 and the second inlet channel 120 are arranged such that, when the main inlet channel 130 is unobstructed downstream, the aerodynamic resistance of the airflow flowing downstream from the first inlet channel 110 via the main inlet channel 130 is smaller than the aerodynamic resistance of the airflow flowing from the first inlet channel 110 via the main inlet channel 130 to the second inlet channel 120.

[0070] In a preferred embodiment, the first inlet passage 110 and the second inlet passage 120 extend downstream in substantially the same direction relative to the airflow 200 in the engine bypass. Figure 2 The first inlet channel 110 and the second inlet channel 120 extend substantially parallel to each other.

[0071] More preferably, the flow cross-sectional area of ​​the first inlet channel 110 gradually decreases along the flow direction from the first air inlet 111, and the flow cross-sectional area of ​​the second inlet channel 120 gradually increases along the flow direction from the second air inlet 121, so that the air flow velocity inside the confluence of the two inlet channels is closer, which is beneficial to avoid the loss of aerodynamic efficiency caused by the mixing of the two airflows at the intersection.

[0072] The following briefly describes the basic working mode of the engine fan air intake structure according to the present invention:

[0073] When the fan air valve of the air source system is opened, the dual inlets simultaneously draw air from the engine duct to the air source system to ensure the normal operation of the air source system. The internal flow field diagram is shown in the figure. Figure 3 As shown in;

[0074] Under certain specific working conditions, when the fan air valve is closed, the flow field inside the entire component is as follows: Figure 4 The airflow enters the cavity from the first inlet channel 110, forms several vortex structures of different sizes in the space upstream of the valve, and consumes part of the energy of the airflow, and finally the airflow flows out of the cavity from the second inlet channel 120 and returns to the outer duct.

[0075] Preferred embodiments of the present invention have been described above in detail, but it should be understood that aspects of the embodiments can be modified, if necessary, to employ aspects, features and concepts of the various patents, applications and publications to provide further embodiments.

[0076] Various changes can be readily appreciated in light of the above detailed description, and can be made to the embodiments described herein.

[0077] In general, in the claims, the terms used should not be considered limited to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which the claims are entitled.

Claims

1. An aircraft engine fan air inlet structure, the aircraft engine fan air inlet structure is used to introduce the airflow (200) in the engine outer duct into the downstream air source system, in, The aircraft engine fan air inlet structure comprises: A first air intake inlet (111) and a second air intake inlet (121) are arranged on the surface of the fairing device (300) in the engine outer duct; a first inlet channel (110), the first inlet channel (110) being in communication with the first air inlet (111) and extending downstream from the first air inlet (111); a second inlet passage (120), the second inlet passage (120) being in communication with the second air intake inlet (121) and extending downstream from the second air intake inlet (121); and A main inlet channel (130), the main inlet channel (130) being directly connected to both the first inlet channel (110) and the second inlet channel (120) downstream of the first inlet channel (110) and the second inlet channel (120), wherein the main inlet channel (130) is configured so that the first air intake inlet (111) can be connected to the second air intake inlet (121) via the first inlet channel (110), the main inlet channel (130) and the second inlet channel (120) in sequence.

2. The aircraft engine fan air inlet structure according to claim 1, It is characterized in that The first air intake inlet (111) is located upstream of the second air intake inlet (121) in the flow direction (A) of the airflow (200) in the engine duct.

3. The aircraft engine fan air inlet structure according to claim 1, It is characterized in that The first inlet channel (110) and the second inlet channel (120) are arranged so that, when the main inlet channel (130) is unobstructed downstream, the aerodynamic resistance of the airflow flowing from the first inlet channel (110) via the main inlet channel (130) to the downstream is smaller than the aerodynamic resistance of the airflow flowing from the first inlet channel (110) via the main inlet channel (130) to the second inlet channel (120).

4. The aircraft engine fan air inlet structure according to claim 3, It is characterized in that The first inlet passage (110) and the second inlet passage (120) extend downstream in substantially the same direction relative to the airflow (200) within the engine duct.

5. The aircraft engine fan air inlet structure according to claim 1, It is characterized in that The first air inlet (111) and the second air inlet (121) are substantially rectangular inlet openings.

6. The aircraft engine fan air inlet structure according to claim 5, It is characterized in that The long side of the rectangle is arranged substantially perpendicular to the flow direction (A) of the airflow (200) in the engine duct.

7. The aircraft engine fan air intake structure according to claim 1, It is characterized in that The ratio of the area of ​​the first air inlet (111) to the area of ​​the second air inlet (121) is between 2:1 and 5:

1.

8. The aircraft engine fan air inlet structure according to claim 7, It is characterized in that The flow cross-sectional area of ​​the first inlet channel (110) gradually decreases along the flow direction starting from the first air inlet (111), and the flow cross-sectional area of ​​the second inlet channel (120) gradually increases along the flow direction starting from the second air inlet (121).

9. The aircraft engine fan air inlet structure according to claim 8, It is characterized in that The first inlet channel (110) maintains a flow cross-sectional shape similar to that of the first air inlet (111), and / or The second inlet passage (120) maintains a flow cross-sectional shape similar to that of the second air intake inlet (121).

10. An aircraft comprising: An aircraft engine fan air inlet structure according to any one of claims 1 to 9; as well as A downstream air source system is located downstream of the aircraft engine fan air intake structure.

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