Injector for de-icing device for aircraft turbojet nacelle air inlet and related method

Abstract

An ejector (3) for a de-icing device for an air inlet (2) of an aircraft turbojet nacelle (1), the ejector (3) comprising an annular piece (30) internally provided with a flow duct (6), the annular piece (30) comprising an annular nozzle (31) configured to eject an annular hot airflow (FAC) to flow a fresh airflow (FAF) in the flow duct (6) from upstream to downstream, the annular member (30) comprises an inner flow guide wall (301) downstream of the annular nozzle (30), the annular member (30) comprising a plurality of rotating members (4) for rotating the hot gas flow (FAC) during injection.

Description

Technical Field

[0001] The present invention relates to the field of aircraft turbojet engines, and more particularly to an ejector for a deicing device of an air inlet of a nacelle of an aircraft turbojet engine. Background Art

[0002] As is known, an aircraft comprises one or more turbojet engines, making it possible to propel the aircraft by accelerating the air flow that circulates back and forth in the turbojet engines.

[0003] refer to Figure 1 , which shows a turbojet 100 extending along a turbojet axis X and comprising a fan 101, which is mounted in a manner capable of rotating about the turbojet axis X in a nacelle comprising a casing 102. In the following, the terms "front" and "rear" are defined relative to the flow direction of the airflow F. The turbojet 100 comprises, at its front end, an air inlet 200, which comprises a cavity 204, which extends annularly about the turbojet axis X and comprises an inner wall 201 facing the turbojet axis X and an outer wall 202 opposite the inner wall 201, the inner and outer walls 201, 202 being connected by a leading edge 203, also called "inlet duct edge". In this way, the air inlet 200 makes it possible to separate the incoming airflow F into an inner airflow FINT guided by the inner wall 201 and an outer airflow FEXT guided by the outer wall 202. In the following, the terms "inner" and "outer" are defined radially relative to the turbojet axis X.

[0004] As is known, during the flight of an aircraft, due to temperature and pressure conditions, ice may accumulate at the leading edge 203 and the inner wall 201 of the air inlet 200 and form ice blocks that may be sucked into the turbojet engine 100. Such ingestion needs to be avoided in order to increase the service life of the turbojet engine 100 and reduce failures.

[0005] To avoid ice accumulation, refer to Figure 1 It is known that the hot air flow FAC is circulated in the inner cavity 204 to heat the inner wall 201 by thermal convection, so that the ice cubes are melted during the accumulation process, thereby avoiding the accumulation of ice cubes.

[0006] like Figure 2 As shown, the hot gas flow FAC is introduced into the inner cavity 204 by a conventional ejector 300 having a cylindrical tube cross section, the cylindrical tube being oriented perpendicular to the direction of the turbine reactor axis X. The hot gas flow FAC flows in an annular shape in the inner cavity 204 to heat the inner wall 201 .

[0007] In practice, such heating is less energy efficient, since the hot air flow FAC is not uniformly mixed with the fresh air flow already in the inner cavity 204. This can lead to hot spots at the air inlet 200, thus shortening its service life.

[0008] It has been proposed to use an ejector comprising an annular member in which a flow duct is arranged. The annular member comprises an annular nozzle configured to eject an annular hot gas flow to cause a fresh gas flow to flow in the flow duct. When the cross section of the flow duct is large, the performance of such an ejector is high, and an optimal mixing between the fresh gas flow and the hot gas flow can be achieved.

[0009] The installation of an injector with a large annular member is complicated because the injector must be removable through the mounting hole for maintenance. In addition, in order to be able to be removed through the mounting hole with a determined size, the size of the annular member must be reduced. Summary of the invention

[0010] The present invention relates to an ejector for a deicing device of an aircraft turbojet engine nacelle air inlet, the ejector comprising an annular member with a flow duct arranged inside, the annular member comprising an annular nozzle, the annular nozzle being configured to eject an annular hot air flow so that a fresh air flow flows from upstream to downstream in the flow duct, the annular member comprising an inner guide wall located downstream of the annular nozzle, the annular member comprising a plurality of rotating members for rotating the hot air flow during ejection.

[0011] The annular member is annular and comprises an annular nozzle configured to eject an annular hot gas flow. The annular nozzle has a closed contour.

[0012] Due to the present invention, the fresh airflow flows concentrically with the hot airflow, so that the fresh airflow can be accelerated by the hot airflow, while promoting the mixing of the fresh airflow and the hot airflow. The inner guide wall helps to form a negative pressure area upstream of the flow duct, thereby accelerating the flow of the fresh airflow from upstream to downstream, while guiding the hot airflow to cling to the inner guide wall.

[0013] The use of a rotating member also further promotes mixing by creating turbulence at the interface between the hot and fresh gas streams. Advantageously, such an ejector remains effective even for an annular member of small diameter, preferably a diameter of less than half the distance between the dividing wall and the leading edge of the air inlet (i.e. its front end). Preferably, the diameter of the annular member is less than 150 mm.

[0014] Advantageously, the inner cavity of the air inlet is heated by a mixed airflow with an optimum temperature, having a high flow rate for optimum heat transfer with the wall, reducing the occurrence of hot spots. This improves de-icing performance while reducing overall dimensions.

[0015] In a preferred aspect, the ejector comprises a supply member connected to the annular member, the supply member comprising mounting feet, the mounting feet being configured to be connected to the air inlet to be supplied by the hot gas flow. Such an ejector is suitable for being mounted by its mounting feet in a through hole of a conventional air inlet partition wall.

[0016] Preferably, since the supply member extends along the mounting axis and the mounting foot has a channel cross section, the annular member defines an overall cross section in a plane perpendicular to the mounting axis that is smaller than the overall cross section of the channel cross section of the mounting foot. Advantageously, if the mounting foot can be moved through a through hole in a conventional air inlet partition wall, the annular member can also be moved in a similar manner. In other words, this enables the ejector to be removed through the through hole for maintenance, which is advantageous. Due to the rotating member, an annular member of reduced size can be used to achieve optimal mixing, while still enabling conventional maintenance steps.

[0017] Preferably, the annular member comprises an inner flow guide wall, and the inner flow guide wall is located downstream of the annular mouth.

[0018] In one aspect, the annular member includes an inner guide wall and a plurality of rotating members located on the inner guide wall. The use of rotating members on the inner guide wall allows the hot air flow to twist after being ejected, while taking advantage of the fact that the hot air flow is close to the inner guide wall. The arrangement of the rotating members on the inner guide wall means that a larger rotating member can be used to achieve a high level of rotation. Advantageously, the use of rotating members on the inner guide wall allows the fresh air flow flowing in the flow duct to twist, thereby further improving the mixing effect.

[0019] Preferably, the length of the rotating member is at least 90% of the length of the inner guide wall, which enhances the rotation effect. Preferably, the cross section of the rotating member defined perpendicular to the injection axis gradually increases from downstream to upstream, so that the hot air flow can be gradually rotated while having a moderate impact on the fresh air flow.

[0020] According to another aspect, a plurality of rotating elements are arranged in the annular mouth. In this way, the rotating elements are integrated into the annular mouth, thereby ensuring optimal contact with the inner guide wall. Preferably, the length of the rotating elements is between 2 and 20 times the thickness of the annular mouth 31. Preferably, the length of the rotating elements is less than 20 mm.

[0021] Preferably, the annular member comprises an inner flow guide wall, and the inner flow guide wall is smooth.

[0022] Preferably, the annular member is configured to accelerate the fresh airflow by the Coanda effect in the circulation duct. The hot airflow conforms to the outer surface of the annular body to form a negative pressure upstream of the circulation duct, thereby accelerating the fresh airflow from upstream to downstream. In this way, the airflow rate entering the cavity is accelerated without the need for a rotating member. This improves the mixing of the hot airflow with the fresh airflow and promotes the flow of the airflow in the circumferential direction of the cavity.

[0023] Preferably, the annular member has an annular mouth facing downstream. Such annular mouth advantageously enables the hot air flow to fit the outer surface of the annular body to accelerate the fresh air flow, achieving the best pressurization effect.

[0024] Preferably, the inner guide wall comprises a downstream end extending parallel to the injection axis so as to straighten the hot air flow.The hot air flow enables the fresh air flow to be guided and mixed with the fresh air flow in the injection direction.

[0025] Preferably, the inner guide wall opens radially toward downstream.

[0026] Preferably, the inner guide wall can promote the generation of a vacuum area upstream of the flow duct so as to accelerate the fresh airflow from upstream to downstream, while guiding the inner guide wall to be close to the hot airflow.

[0027] Preferably, the annular member comprises a heating chamber supplied with a hot gas flow, the heating chamber comprising an injection channel arranged adjacent to the annular nozzle, the injection channel being tapered to accelerate the hot gas flow toward the annular nozzle. The tapered injection channel enables to minimize the pressure loss in the hot gas flow. The high speed of the hot gas flow at the injection outlet enables to increase the flow rate of the fresh gas flow by entrainment.

[0028] Preferably, the annular member comprises an annular lip extending into the heating chamber and partially defining the injection channel. This enables the injection speed to be conveniently adjusted to achieve a desired pressurization effect.

[0029] Preferably, the annular lip extends continuously with the inner guide wall. This allows the annular member to be formed in a practical manner without assembly. Preferably, the walls of the annular member are made of the same material.

[0030] According to one aspect of the present invention, the inner guide wall is inclined at 5°-45°, preferably 10°-15°, and even more preferably 12° relative to the injection axis. This inclination angle enables the best Coanda effect to be generated, thereby achieving efficient airflow acceleration and mixing.

[0031] In one aspect, each rotating member includes an upstream portion and a downstream portion, the upstream portion and the downstream portion being circumferentially offset to rotate the hot gas flow.

[0032] The present invention also relates to a deicing device for an air inlet of an aircraft turbojet engine nacelle extending along an axis of the turbojet engine, the air inlet comprising an inner cavity, the inner cavity extending in a ring around the turbojet engine axis and comprising an inner wall facing the turbojet engine axis and an outer wall opposite to the inner wall, the inner and outer walls being connected by a leading edge, the deicing device comprising at least one ejector as described above, for ejecting a hot air flow into the inner cavity along an ejection axis extending from upstream to downstream.

[0033] The present invention also relates to an air inlet of an aircraft turbojet engine nacelle extending along an axis, the air inlet comprising an inner cavity, the inner cavity extending in a ring around the axis and comprising an inner wall facing the axis and an outer wall opposite to the inner wall, the inner and outer walls being connected by a leading edge, the air inlet comprising a de-icing device as described above.

[0034] The present invention also relates to a method for deicing an air inlet of an aircraft turbojet nacelle extending along an axis of the turbojet engine using a deicing device as described above, wherein the air inlet comprises an inner cavity extending in a ring around the axis and comprising an inner wall facing the axis of the turbojet engine and an outer wall opposite to the inner wall, wherein the inner and outer walls are connected by a leading edge.

[0035] The method comprises the following steps: injecting a twisted annular hot air flow to make a fresh air flow flow in the circulation duct, the fresh air flow flows from upstream to downstream relative to the injection axis, and the fresh air flow flows inside the annular hot air flow to achieve mixing between the hot air flow and the fresh air flow. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The invention will be better understood by reading the following description, given by way of example only, and by reference to the following drawings, given by way of non-limiting example, in which like reference numerals refer to similar objects, and in which:

[0037] Figure 1 It is a schematic diagram of a nacelle air inlet of the prior art.

[0038] Figure 2 is a schematic cross-sectional view of the flow of hot air flow in an air intake in the prior art.

[0039] Figure 3 Schematic diagram of the nacelle air inlet of the present invention.

[0040] Figure 4 is a schematic diagram of the downstream end of an injector according to an embodiment of the present invention.

[0041] Figure 5 A schematic cross-sectional view of an injector is shown.

[0042] Figure 6 It is a schematic diagram of an angular cross section of the annular member of the ejector.

[0043] Figure 7 is a schematic diagram of the injector of the first embodiment.

[0044] Figure 8 is a cross-sectional view of the injector of the first embodiment.

[0045] Fig. 9 is another schematic diagram of the injector of the first embodiment.

[0046] Fig.10 It is a partial schematic diagram of the injector of the second embodiment.

[0047] Fig.11 It is a close-up view of the ejector of the second embodiment.

[0048] Fig.12 is a schematic cross-sectional view of an annular member of an ejector, wherein the flow of hot gas flow through the annular member and its rotation are shown.

[0049] Fig.13 Schematic cross-sectional view of the hot gas flow in the air intake of the present invention.

[0050] It should be noted that the accompanying drawings illustrate the present invention in order to realize the present invention and can of course be used to better define the present invention when necessary. DETAILED DESCRIPTION

[0051] refer to Figure 3, shows a turbojet 1 extending along a turbojet axis X and comprising a fan 10, which is mounted in a manner capable of rotating about the turbojet axis X in a nacelle comprising a casing 12. In the following, the terms "front" and "rear" are defined relative to the flow direction of the airflow F. The turbojet 1 comprises at its front end an air inlet 2, which comprises an inner cavity 20, which extends annularly around the turbojet axis X and comprises an inner wall 21 facing the turbojet axis X and an outer wall 22 opposite the inner wall 21. The inner wall 21 and the outer wall 22 are connected by a leading edge 23, also called "inlet lip". In this way, the air inlet 2 makes it possible to separate the incoming airflow F into an internal airflow FINT guided by the inner wall 21 and an external airflow FEXT guided by the outer wall 22. In the following, the terms "inner" and "outer" are defined radially relative to the turbojet axis X. The inner wall 21 and the outer wall 22 connected via the leading edge 23 delimit the inner cavity 20 at the front. In this example, the inner cavity 20 is delimited at the rear by a partition wall 24 .

[0052] The inner cavity 20 is filled with a fresh air flow FAF, such as a stagnant air flow or a hot air flow that was previously ejected and cooled.

[0053] The turbojet engine 1 comprises a deicing device for removing ice that has accumulated on the air inlet 2. As is known, the deicing device comprises an ejector 3 for ejecting a hot air flow FAC into the inner cavity 20. The flow of the hot air flow FAC enables the ice to be melted during the accumulation process by thermal convection, thereby avoiding the accumulation of ice. Preferably, the hot air flow FAC comes from the turbojet engine 1.

[0054] like Figure 4 As shown, the ejector 3 comprises an annular member 30 in which a flow channel 6 is provided. The flow channel 6 is through. In this example, the annular member 30 is circular, but it goes without saying that it can have any other annular shape, such as an elongated shape, specifically an elliptical shape. Figure 4 , the flow channel 6 has a disc-shaped cross section, but other shapes are of course also applicable.

[0055] like Figure 5 As shown, the annular member 30 extends along the injection axis X3, and the flow duct 6 extends along this axis. Figure 5 In this example, the injection axis X3 extends from upstream to downstream. Fig.13 , the injection axis X3 extends approximately tangentially / perpendicularly to the axis X of the turbojet engine.

[0056] like Figure 4 and Figure 6As shown, the annular member 30 comprises an annular nozzle 31, which is configured to spray the hot gas flow FAC from upstream to downstream along the spray axis X3. The annular nozzle 31 is similar in shape to the annular member 30. In this example, the annular nozzle 31 is circular and faces downstream.

[0057] refer to Figure 4 , the annular member 30 comprises a heating chamber 33 and a supply member 32, which is configured to supply a hot air flow FAC to the heating chamber 33. The supply member 32 is preferably in the form of a hollow cover. In this example, the supply member 32 comprises a mounting foot 39, which is configured to be connected to the air inlet 2, specifically to the partition wall 24. Figure 4 As shown, the supply element 32 extends along a mounting axis XM, which is preferably substantially parallel to the turbojet engine axis X (see Figure 3 ), which may of course be different. The heating chamber 33 defines a radial inner wall and a radial outer wall. The flow conduit 6 extends inside the radial inner wall.

[0058] like Figure 4 As shown, the mounting foot 39 defines a passage section S1 relative to said mounting axis XM. In this example, the mounting foot 39 is disc-shaped and the passage section corresponds to the surface of said disc. It goes without saying that the shape of the mounting foot 39 can be different. In practice, the mounting foot 39 is mounted in a through hole OM formed in the partition wall 24, the section of which is substantially similar to that of the mounting foot 39. During maintenance operations, the injector 3 is moved along the mounting axis XM through the through hole OM.

[0059] The annular piece 30 defines an overall section S2 on a plane perpendicular to the mounting axis XM that is smaller than the passage section S1 so that the ejector 3 can be removed through the through hole OM. This size limitation enables the ejector 3 to achieve optimal mixing of the hot air flow FAC and the fresh air flow FAF.

[0060] refer to Figure 5 , the annular nozzle 31 is configured to eject an annular hot air flow FAC from the heating chamber 33 so that the fresh air flow FAF flows in the circulation duct 6. The fresh air flow FAF flows from upstream to downstream relative to the ejection axis X3, and the fresh air flow FAF flows inside the annular hot air flow FAC to achieve mixing between the hot air flow FAC and the fresh air flow FAF. As will be shown later, the hot air flow FAC has a twisting motion when ejected and is annular.

[0061] like Figure 5 As shown, the hot air flow FAC is annular, in this case with an annular cross section, and the fresh air flow FAF is axially guided inside the hot air flow FAC along the injection axis X3. In other words, the hot air flow FAC and the fresh air flow FAF are concentric. As will be shown below, Figure 5As shown, the annular member 30 is configured to accelerate the fresh air flow FAF in the flow duct 6 through the Coanda effect.

[0062] refer to Figure 5 , the hot air flow FAC is guided by the surface of the annular member 30 to achieve high-speed injection. This generates a negative pressure area downstream of the annular mouth 31, which can suck in the fresh air flow FAF located upstream of the annular mouth 31. In other words, due to the injection of the hot air flow FAC, the fresh air flow FAF is drawn downstream along the injection axis X3, which increases its speed in a manner similar to a bladeless fan.

[0063] Advantageously, reference Figure 5 The negative pressure generated downstream can also suck in the fresh air flow FAF that has bypassed the circulation duct 6, thereby generating turbulence T downstream of the annular member 30. Such turbulence T is beneficial because it is conducive to the mixing between the hot air flow FAC and the fresh air flow FAF, thereby avoiding the occurrence of hot spots in the inner cavity 20.

[0064] refer to Figure 6 , roughly shows a longitudinal section of the annular member 30 along the injection axis X3. The annular member 30 comprises a section having an inner flow guide wall 301, an outer wall 302, an upstream wall 303 and a downstream wall 304. These walls together define the interior of the heating chamber 33. Preferably, the walls 301-304 of the annular member 30 are made of the same material.

[0065] refer to Figure 6 The upstream wall 303 is preferably convex and flow-conducting to allow the fresh air flow FAF to flow without turbulence. The upstream wall 303 is used to guide the fresh air flow FAF into the flow duct 6 to accelerate the fresh air flow, and at the same time guide the fresh air flow FAF out of the annular member 30 to generate turbulence T downstream. The outer wall 302 is cylindrical so as to axially guide the fresh air flow FAF bypassing the flow duct 6.

[0066] In this example, the inner guide wall 301 expands from upstream to downstream, that is, it opens radially from upstream to downstream. In other words, the flow duct 6 has an increasing cross-section. The inner guide wall 301 is located downstream of the annular mouth 31 so as to guide the hot air flow FAC out of the annular mouth 31 to produce the Coanda effect. As will be shown later, the hot air flow FAC flows against the inner guide wall 301, which makes it possible to accelerate the fresh air flow FAF to be sucked in. Fig.12 The inner guide wall 301 is inclined relative to the injection axis X3, and the inclination angle θ is between 5° and 45°, so as to obtain the best Coanda effect. Preferably, the inclination angle θ is between 10° and 15°, preferably 12°. Advantageously, the annular nozzle 31 is extended to be able to inject along the inner guide wall 301. The hot air flow FAC is therefore close to the inner guide wall 301.

[0067] In this example, the inner guide wall 301 includes a downstream end 301a extending along the injection axis X3. The downstream end 301a straightens the hot air flow FAC so that the fresh air flow FAF can be guided along the injection axis X3.

[0068] refer to Fig.12 , the downstream wall 304 is configured to amplify the turbulence T, and in this example is of non-guided truncation type. To achieve ultra-high-speed injection through the annular nozzle 31, the heating chamber 33 includes an injection channel 34 arranged adjacent to the annular nozzle 31. Preferably, the injection channel 34 is of a tapered type so as to accelerate the hot air flow FAC when it is injected through the annular nozzle 31. Preferably, as Fig.12 As shown, the annular member 30 comprises an annular lip 35 extending into the heating chamber 33 and partially defining the injection channel 34. Such annular lip 35 makes it possible to precisely define the shape of the injection channel 34 and thus precisely define the desired compression. Preferably, the annular lip 35 extends continuously with the inner guide wall 301 so as to form an annular mouth 31 between the inner guide wall 301 and the upstream wall 303 of the annular member 30.

[0069] According to the invention, the annular member 30 comprises a plurality of rotating members for rotating the hot air flow FAC when it is ejected into the inner cavity 20 of the air inlet 2. As will be explained in more detail later, these rotating members make it possible to generate a twist on the hot air flow FAC while keeping the hot air flow close to the inner guide wall 301, so as to achieve an optimal suction of the fresh air flow FAF. This type of twist makes it possible to improve the mixing of the hot air flow FAC with the fresh air flow FAF while keeping the ejector 3 small.

[0070] Preferably, the inclination angle of the rotating member relative to the injection axis is between 20° and 40° to obtain the desired twisting effect. Figure 8 As shown, each rotating member 4 comprises an upstream portion 4A and a downstream portion 4B offset in the circumferential direction to rotate the hot air flow FAC. Preferably, the ratio of the length of the rotating member to the distance between the two rotating members is between 1-1.4 to achieve a compromise between the number of rotating members and the deflection capacity.

[0071] In the first embodiment, reference Figures 7 to 9 , a plurality of rotating members 4 are arranged on the inner guide wall 301. Each rotating member 4 protrudes toward the injection axis X3 so as to form a protrusion on the inner guide wall 301. Preferably, the rotating member 4 is a protrusion formed between two grooves.

[0072] Preferably, the number, shape and length of the rotating members 4 are adapted to obtain the desired twisting effect. Preferably, the length of the rotating member 4 is at least 90% of the length of the inner guide wall 301. Preferably, the cross section of the rotating member 4 is defined perpendicular to the injection axis X3, and gradually increases from downstream to upstream, so that the hot air flow FAC and the fresh air flow FAF can be gradually rotated via the rotating member 4.

[0073] Preferably, the rotating members 4 are evenly distributed around the periphery of the inner guide wall 301 to obtain a uniform twisting effect. In this example, the rotating members 4 and the inner guide wall 301 are made of the same material.

[0074] Therefore, when the hot air flow FAC is ejected through the annular nozzle 31, the hot air flow FAC is close to the inner guide wall 301, thereby driving it to rotate at high speed, which will cause suction of the fresh air flow FAF and generate turbulence due to the rotation, thereby improving the mixing between the hot air flow FAC and the fresh air flow FAF.

[0075] In the second embodiment, reference Figure 10 to Figure 11 , a plurality of rotating members 5 are located in the annular mouth 31. Preferably, the number, shape and length of the rotating members 5 are adapted to obtain the desired twisting effect. Preferably, the length of the rotating member 5 is between 2-20 times the thickness of the annular mouth 31 to achieve rotation while keeping the overall size of the annular mouth 31 small. Preferably, the length of the rotating member 5 is less than 20 mm.

[0076] Preferably, the rotating members 5 are evenly distributed around the periphery of the annular mouth 31 in order to obtain a uniform twisting effect. In this example, the rotating members 5 and the annular member 30 are made of the same material. Preferably, the inner guide wall 301 is kept smooth to avoid interfering with the suction of the fresh air flow FAF. Preferably, each rotating member 5 is of fin type.

[0077] Therefore, when the hot air flow FAC is ejected through the annular nozzle 31, the hot air flow FAC is twisted and then closely adheres to the inner guide wall 301. This generates suction of the fresh air flow FAF and generates turbulence through rotation, thereby improving the mixing between the hot air flow FAC and the fresh air flow FAF. In this embodiment, the rotating member 5 does not rotate the fresh air flow FAF.

[0078] It goes without saying that the different embodiments are compatible and that the ejector 3 may include rotating elements in the annular mouth 31 and on the inner guide wall 301 .

[0079] In the above two embodiments, Figure 4As shown, the overall cross section S2 defined by the annular member 30 on a plane perpendicular to the mounting axis XM is smaller than the channel cross section S1 of the mounting foot 39. Maintenance can be performed in a practical manner. Preferably, the diameter of the channel cross section S1 defining the maintenance channel is between 40 mm and 150 mm, so that the channel cross section can be adapted to existing deicing devices. Preferably, the diameter of the annular member 30 is between 35 mm and 140 mm. Preferably, there is a gap between the diameter of the channel cross section S1 and the diameter of the overall cross section S2, the gap being between 5 mm and 10 mm.

[0080] Preferably, the annular member 30 has a smaller diameter, which is preferably smaller than the distance d ( Figure 3 Preferably, the diameter of the annular member 30 is less than 140 mm.

[0081] An example of implementation of a method using the deicing device according to the present invention will now be presented. The method comprises the step of injecting an annular hot air flow FAC into the inner cavity 20 so that a fresh air flow FAF flows in the circulation duct 6. The fresh air flow FAF flows from upstream to downstream inside the hot air flow FAC relative to the injection axis X3, and the hot air flow is annular and twisted, such as Fig.12 and Fig.13 shown.

[0082] When injected, the hot air flow FAC is rotated by the rotating elements 4 , 5 of the annular element 30 , which increases turbulence and improves mixing with the fresh air flow FAF, while maintaining small overall dimensions.

[0083] The hot air flow FAC is injected into the heating chamber 33 at a very high speed by the injection channel 34 due to optimal compression. When injected, the hot air flow FAC fits the inner guide wall 301, thereby forming a negative pressure in the circulation duct 6, which draws in the fresh air flow FAF upstream. Therefore, when the hot air flow FAC is injected, the fresh air flow FAF is accelerated, thereby increasing the air flow rate in the inner chamber 20 of the air inlet 2. The heat exchange with the walls 21, 22, and 23 of the air inlet 2 is improved, thereby preventing ice accumulation.

[0084] like Fig.13 As shown, when the fresh air flow FAF flows inside the annular and twisted hot air flow FAC, the hot air flow is mixed with the fresh air flow at the outlet of the ejector 3 to form a mixed air flow FAM with an optimal temperature. In other words, the risk of forming hot spots in the air intake 2 is reduced. The service life of the air intake 2 is increased. Such an ejector 3 can be installed in an existing air intake 2 through a through hole OM formed in the inner partition wall 24 of the air intake 2.

[0085] In addition, due to the characteristics of the annular member 30, turbulence T occurs downstream of the annular member 30, which makes the fresh air flow FAF and the hot air flow FAC mixed more evenly. Therefore, the mixed air flow FAM ensures even heating of the walls 21, 22, 23 of the air inlet 2.

[0086] Thanks to the invention, a mixed air flow FAM having an optimum temperature and a high flow rate flows in the inner cavity 20 , thereby de-icing the walls 21 , 22 , 23 of the air inlet 2 .

Claims

1. An ejector (3) for a deicing device for an air inlet (2) of a nacelle (1) of an aircraft turbojet engine, characterized in that: The ejector (3) comprises an annular member (30), a flow duct (6) is arranged inside the annular member (30), the annular member (30) comprises an annular mouth (31), the annular mouth (31) is configured to eject an annular hot air flow (FAC) so that a fresh air flow (FAF) flows from upstream to downstream in the flow duct (6), the annular member (30) comprises an inner guide wall (301) located downstream of the annular mouth (30), and the annular member (30) comprises a plurality of rotating members (4, 5) for rotating the hot air flow (FAC) during ejection.

2. The injector (3) according to claim 1, characterized in that The ejector (3) comprises a supply member (32) connected to the annular member (30), the supply member (32) comprising a mounting foot (39) configured to be connected to the air inlet (2) to be supplied by the hot gas flow (FAC).

3. The injector (3) according to claim 2, characterized in that The supply member (32) extends along the installation axis (XM), the installation foot (39) includes a channel section (S1), and the overall section (S2) defined by the annular member (30) on a plane perpendicular to the installation axis (XM) is smaller than the overall section of the channel section (S1) of the installation foot (39).

4. The injector (3) according to any one of claims 1 to 3, characterized in that The annular member (30) comprises an inner flow guide wall (301), and the inner flow guide wall (301) is located downstream of the annular mouth (31).

5. The injector (3) according to claim 4, characterized in that The inner flow guide wall (301) opens radially toward the downstream, and a plurality of rotating members (4) are arranged on the inner flow guide wall (301).

6. The injector (3) according to claim 4, characterized in that The inner flow guide wall (301) is smooth.

7. The injector (3) according to any one of claims 1 to 6, characterized in that The plurality of rotating members (5) are all arranged in the annular mouth (31).

8. The injector (3) according to any one of claims 1 to 7, characterized in that Each rotating member (4) comprises an upstream portion (4A) and a downstream portion (4B), both of which are offset in the circumferential direction to rotate the hot air flow (FAC).

9. A deicing device for an air inlet (2) of a nacelle (1) of an aircraft turbojet engine extending along the turbojet engine axis (X), characterized in that: The air inlet (2) comprises an inner cavity (20), which extends in a ring around the axis (X) of the turbojet engine and comprises an inner wall (21) facing the axis (X) of the turbojet engine and an outer wall (22) opposite to the inner wall (21), the inner wall (21) and the outer wall (22) being connected by a leading edge (23), and the deicing device comprises at least one ejector (3) according to any one of claims 1 to 8, for ejecting a hot air flow (FAC) into the inner cavity (20) along an ejection axis (X3) extending from upstream to downstream.

10. An air inlet (2) of a nacelle (1) of an aircraft turbojet engine extending along the turbojet engine axis (X), characterized in that: The air inlet (2) comprises an inner cavity (20), which extends in a ring around the axis (X) of the turbojet engine and comprises an inner wall (21) facing the axis (X) of the turbojet engine and an outer wall (22) opposite to the inner wall (21), the inner wall (21) and the outer wall (22) being connected by a leading edge (23), and the air inlet (2) comprises a de-icing device as claimed in claim 9.

11. A method for deicing an air inlet (2) of a nacelle (1) of an aircraft turbojet engine extending along a turbojet engine axis (X) using a deicing device according to claim 9, wherein the air inlet (2) comprises an inner cavity (20), the inner cavity (20) extending in an annular manner around the turbojet engine axis (X) and comprising an inner wall (21) facing the turbojet engine axis (X) and an outer wall (22) opposite to the inner wall (21), the inner wall (21) and the outer wall (22) being connected by a leading edge (23), characterized in that The method comprises the following steps: injecting an annular and twisted hot air flow (FAC) to make a fresh air flow (FAF) flow in the circulation duct (6), the fresh air flow (FAF) flows from upstream to downstream relative to the injection axis (X3), and the fresh air flow (FAF) flows inside the annular hot air flow (FAC) to achieve mixing between the hot air flow (FAC) and the fresh air flow (FAF).

Images