Turbomachine discharge conduit and active actuation

Abstract

Intermediate casing hub (10) for an aircraft turbomachine, comprising: an inner shell (12) for delimiting a first flow space (24) for a first airflow (F1) from the turbomachine, the inner shell comprising a portion having an air passage orifice (27), at least one relief valve (30) comprising a flap (28) movable between an open and a closed position of said inlet orifice, an outer portion (140) for delimiting a second flow space (32) for a second airflow (F2) from the turbomachine, the outer portion comprising a portion having an air passage orifice (42), a discharge conduit (44), the conduit being configured to guide an airflow (F3) from the first flow space to the second flow space, a suction device (700) for drawing the airflow (F3) from the first flow space in the vein conduit. Figure for the abbreviation: Fig. 3.

Description

Title of the invention: Discharge duct of a turbomachine and active actuation technical field

[0001] The invention relates to the general field of aircraft turbomachinery, and more particularly to relief valves allowing the regulation of the air at the outlet of a compressor of such a turbomachine, said valves sometimes being designated by their English acronyms VBV (Variable Bleed Valves). Previous technique

[0002] A turbomachine can generally comprise, from upstream to downstream in the direction of gas flow, a shrouded fan, an annular primary flow space, and an annular secondary flow space. The mass of air drawn in by the fan is thus divided into a primary flow Fl, which circulates in the primary flow space, and a secondary flow F2, which is concentric with the primary flow Fl and circulates in the secondary flow space.

[0003] The primary flow space passes through a primary body comprising one or more compressor stages, for example a low pressure compressor and a high pressure compressor, a combustion chamber, one or more turbine stages, for example a high pressure turbine and a low pressure turbine, and a gas exhaust nozzle.

[0004] In a manner known per se, the turbomachine also includes an intermediate housing whose hub is arranged between the low-pressure compressor housing and the high-pressure compressor housing. The intermediate housing includes relief valves or VBVs, whose role is to regulate the flow rate at the inlet of the high-pressure compressor in order, in particular, to limit the risk of pumping of the low-pressure compressor by venting some of the air outside the primary flow space.

[0005] As illustrated in [Fig. 1], which is a partial axial cross-sectional view of a known type of twin-body, twin-flow aircraft turbomachine, the hubs 10 of the intermediate casings 11' of the aforementioned type usually comprise two coaxial annular ferrules, respectively internal 12' and external 14', mutually connected by two transverse flanges, respectively upstream 16' and downstream 18'.

[0006] The upstream flange 16' is arranged downstream of a low pressure compressor 20' of the turbomachine while the downstream flange 18' is arranged upstream of a high pressure compressor 22' of the turbomachine.

[0007] The inner shell 12' delimits an annular space 24' for the flow of a primary flow Fl' from the turbomachine, and is generally connected to structural arms 26' passing through this space 24'. In addition, the inner shell 12' has one or more air passage orifices 27', referred to as inlet orifices in what follows, each of which is closed by the pivoting flap 28' of a corresponding relief valve 30' intended for regulating the flow of the high-pressure compressor 22'.

[0008] Such a relief valve usually takes the form of a gate which has the flap 28' at its radially internal end and which is pivotally mounted on the internal ferrule 12' about an axis 31' so that in the closed position of the inlet ports 27', the flap 28' extends the internal ferrule 12' of the housing in a substantially continuous manner to minimize the risk of aerodynamic disturbances of the primary flow Fl' by this flap 28', and that in the open position of said ports 27', the flap 28' protrudes radially outwards relative to the aforementioned internal ferrule 12', the flap 28' opening in the intermediate space 50, and thus forms a trap for sampling a portion of the primary flow.

[0009] The outer ring 14' delimits the secondary flow space 32' of the secondary flow F2' of the turbomachine, and includes one or more air passage outlets 43', generally in the form of grille(s) or fin(s), into which the airflow from the primary flow Fl' is drawn through air passage orifices 42', referred to as outlet orifices hereafter. When the outer ring 14' of the hub 10' of the intermediate casing 11' carries structural arms extending into a flow space 32' of a secondary flow of the turbomachine and relatively far apart from each other, the evacuation of air or debris can occur through this outer ring 14'. When, as in the example shown in [Fig.1], the outer ferrule 14' has guide vanes 34' relatively close to each other, the latter hinder the aforementioned evacuation through the outer ferrule 14'.In this case, and more generally when it is advantageous, it may therefore be desirable to allow this evacuation further downstream, through the annular wall 36' of an extension 38' of the hub 10' of the intermediate casing 11'. Here, an extension 38' is understood to be a structural part which is sometimes used to support thrust reverser elements such as fairing panels at its downstream end.

[0010] The turbomachine further includes discharge channels, formed between the inlet ports 27' and the outlet ports 42'. Each discharge channel is delimited, from upstream to downstream between an associated inlet port 27' and outlet port 42', by an annular intermediate space 50', delimited by the ferrules 12', 14' and the flanges 16', 18', then by a discharge channel 44', configured to guide an airflow F3' from the secondary flow space, from the intermediate space to the secondary flow space.

[0011] The downstream transverse flange 18' may be provided with one or more air passage orifices 40', referred to as intermediate orifices, arranged respectively downstream of each of the discharge valves 30' and positioned near the primary flow space 24', radially at the same level as the inlet orifices 27' of these discharge valves 30'. The discharge vein conduit 44' may open into the intermediate space 50' at the level of the upstream surface of the downstream transverse flange 18' comprising said intermediate orifices 40' and into the secondary flow space through said outlet orifices 42'. The discharge vein conduit 44' allows air to be guided between the intermediate orifices 40' of the downstream transverse flange 18' and the corresponding orifices 42' and then into the air passage outlets 43' provided in the external ferrule 14', the conduit 44' mutually connecting these intermediate and outlet orifices 40' and 42'.These 44' conduits are generally bent to reduce their axial size, as in [Fig. 1].

[0012] However, despite the relative alignment between the inlet ports 27' and the intermediate ports 40', there remains a high risk that a non-negligible portion of air will hit the flange 18' next to the intermediate ports 40' and remain in the intermediate space 50' of the intermediate housing, generating pressure losses and also reducing the efficiency of the sampling system.

[0013] Furthermore, the extraction and reinjection of air into the turbomachine can become problematic if they disrupt the flow of the turbomachine's secondary airflow. As illustrated in [Fig. 1], the extracted airflow F3' tends to enter the secondary flow space perpendicular to the direction of the secondary airflow F2'. Excessively abrupt air reinjection can induce a local pressure change and disrupt (or even reverse) the airflow. The reinjection angle is a crucial parameter for maximizing the diffusivity of the airflow exiting the duct into the secondary flow space. The smaller the reinjection angle, the smaller the local pressure change. Consequently, the diffusivity of the jet exiting the duct is faster.

[0014] For this purpose, it is known to integrate fins or grids 60' inclined with respect to the flow direction of the secondary flow F2' in order to play on the speed and thus be able to redirect the air flow F3' from the primary flow space Fl' so as to align it as much as possible, and in the same direction, with that of the secondary flow F2' ([Fig.2]).

[0015] This solution, however, has drawbacks because it requires the insertion of an additional part at the outlet ports, which can also locally disrupt the flow. Furthermore, the insertion of a grid or fin requires an additional manufacturing and assembly step. Finally, integrating such a part requires space and its assembly is subject to uncertainties. giving way to ascending and / or descending steps within the secondary flow space. Description of the invention

[0016] The invention aims in particular to overcome at least partially one of these drawbacks and relates, according to a first aspect, to an intermediate housing hub for an aircraft turbomachine, said hub comprising: - an internal shell configured to delimit a first flow space for a first airflow from the turbomachine, the internal shell comprising at least one portion provided with at least one air passage orifice, called the inlet orifice, - at least one discharge valve comprising a movable flap between an open position and a closed position of said inlet orifice, - an external part configured to delimit a second flow space for a second airflow from the turbomachine, the external part comprising at least one portion provided with at least one air passage orifice, called an outlet orifice, - a discharge vein duct, the duct being configured to guide an airflow from the first flow space to the second flow space, - a suction device, for example active, configured to suction the airflow from the first flow space into the discharge vein duct

[0017] According to other features of the invention, the intermediate housing hub of the invention includes one or more of the following optional features.

[0018] The hub may include an intermediate space, delimited by the portion of the inner ferrule provided with said inlet orifice, a portion of the outer part, a first upstream flange and a second downstream flange, the conduit opening on one side into the intermediate space and on the other side into the second flow space, and the suction device being configured to draw the airflow from the intermediate space into the discharge vein conduit.

[0019] The suction device can be arranged in the discharge vein conduit.

[0020] The suction device can be arranged in an upstream end portion of the discharge vein conduit.

[0021] The suction device may include a propeller comprising a plurality of movable blades rotating about an axis.

[0022] The discharge vein conduit can be cylindrical.

[0023] The hub may include a rotation device, for example passive, configured to rotate the airflow from the first flow space in the discharge vein duct.

[0024] The rotation device may include at least one rotation channel, for example a groove and / or a thread, for example at least one channel internal, for example an internal groove and / or an internal thread, for example arranged in the discharge vein conduit.

[0025] The internal channel, for example the internal groove and / or the internal thread, can be a helical channel, for example a helical groove and / or a helical thread.

[0026] According to one aspect, the invention relates to an intermediate housing for an aircraft turbomachine comprising a hub as previously described.

[0027] According to one aspect, the invention relates to an aircraft turbomachine comprising an intermediate housing for an aircraft turbomachine comprising a hub as previously described. Brief description of the drawings

[0028] [Fig-1] The [Fig. 1] is an axial cross-sectional view of a hub for an intermediate housing known from the prior art.

[0029] [Fig.2] Fig.2 schematically represents the principle of air extraction from a first airflow to a second airflow known from the prior art.

[0030] [Fig.3] The [Fig.3] is an axial cross-sectional view of a hub for an intermediate housing according to the invention.

[0031] [Fig.4] Fig.4 schematically represents the operating principle of a suction device according to the invention.

[0032] [Fig.5] The [Fig.5] illustrates a discharge vein conduit and a hub suction device according to the invention.

[0033] [Fig.6] Fig.6 illustrates the discharge vein conduit, the hub suction device and a rotation device according to the invention.

[0034] [Fig.7a] Fig.7a illustrates a perspective view of a grooved section of the device of Fig.6.

[0035] [Fig.7b] The [Fig.7b] illustrates a cross-sectional view of the section of the [Fig.7a] along a vertical plane AA.

[0036]

[0037] [Fig.8a] The [Fig.8a] illustrates a perspective view of a threaded section of the device of the [Fig.6].

[0038] [Fig.8b] The [Fig.8b] illustrates a cross-sectional view of the section of the [Fig.8a] along a vertical plane BB. Description of the implementation methods

[0039] In the following description of the intermediate housing hub, the intermediate housing and the turbomachine according to the invention, the same numerical references designate the same elements.

[0040] In the following description, the upstream and downstream terminals are defined in relation to the flow of the flux, for example primary air, when the intermediate housing hub according to the invention is used in a turbomachine.

[0041] Figure 3 illustrates a partial axial cross-sectional view of an aircraft turbomachine 2, for example a twin-spool, twin-spool turbomachine, which may be similar to that of Figure 1 but which further includes a suction device, for example an active one, configured to draw the airflow from the first flow space into the discharge duct. The twin-spool, twin-spool aircraft turbomachine may, for example, include an intermediate casing hub 11 comprising:

[0042] - an internal ferrule 12 configured to delimit a first flow space 24, for example a primary flow space, of a first air flow for example of a primary air flow Fl, of the turbomachine, the inner shell 12 may include at least a portion provided with at least one air passage orifice 27, for example called an inlet orifice,

[0043] - an external part 140, for example external with respect to the internal ferrule 12, configured to delimit a second flow space 32, for example a secondary flow space, of a second airflow, for example a secondary airflow F2 of the turbomachine, the external part 140 may include at least a portion provided with at least one air passage orifice 42, for example called an outlet orifice

[0044] - a discharge vein conduit 44, which can extend between the inner ferrule and the external part 140.

[0045] By "a conduit" is meant at least one conduit. The hub may comprise a plurality of conduits.

[0046] The inner shell 12 can be connected to structural arms 26 passing through the primary flow space 24. Furthermore, the inner shell 12 can include one or more air passage ports 27, referred to as inlet ports in the following, each of which can be selectively opened or closed / shut off by a pivoting valve 28 of a corresponding relief valve 30 for regulating the flow rate of a high-pressure compressor 22 of the turbomachine, depending on the flight phases of the turbomachine. The valve 28 can be movable between a closed position, in which the valve 28 closes the inlet port 27, and an open position, in which the valve 28 releases the inlet port 27.

[0047] Such a relief valve usually takes the form of a gate which has the valve 28 at its radially internal end and which is pivotally mounted on the internal ferrule 12 about an axis 31 so that in the closed position of the inlet ports 27, the valve 28 extends the internal ferrule 12 of the housing in a substantially continuous manner to minimize the risk of disturbances aerodynamics of the primary flow Fl by this valve 28, and that in the open position of said orifices 27, the valve 28 protrudes radially outwards, for example relative to the aforementioned internal ferrule 12, the valve 28' opening for example in the intermediate space 50, and thus forms a trap for sampling part of the primary flow.

[0048] The external part 140 of the hub 10 of the intermediate housing 11 may include an external ferrule 14.

[0049] The outer shell 14 may carry structural arms that can extend into the flow space 32 of the, for example, secondary flow of the turbomachine. The structural arms may be relatively far apart from each other so that air can be discharged through this outer shell 14. The outer shell 14 may include at least one portion provided with at least one air passage outlet 43 into which the airflow from the primary flow Fl, produced by an outlet 42, is discharged.

[0050] When, as in the example shown in [Fig. 3], the outer ferrule 14 carries guide vanes 34 relatively close to each other, these vanes impede the aforementioned discharge through the outer ferrule 14. In this case, and more generally when it is advantageous, it may therefore be desirable to allow this discharge further downstream, through an annular wall 36 of an extension 38 of the hub 10 of the intermediate housing 11. Here, an extension 38 is understood to be a structural component that is sometimes used to support thrust reverser elements such as fairing panels at its downstream end. Thus, for example, the outer part 140 may include the outer ferrule 14 and the extension 38 of the hub 10 of the intermediate housing 11, which may include, for example, the annular wall 36. For example, the annular wall 36 may be provided with outlet ports 42.

[0051] The turbomachine may further include at least one discharge channel formed between the inlet ports 27 and the outlet ports 42. Each discharge channel may be configured to allow the extraction of an airflow F3 from the primary airflow Fl of the primary flow space 24, for example via the inlet port 27 and a reinjection of said extracted airflow F3 into the secondary flow space 32, for example via the outlet port 42 and the air passage outlet 43.

[0052] Each discharge vein can be delimited, from upstream to downstream, by an annular intermediate space 50 and / or by a discharge vein conduit 44.

[0053] Also, the hub can include an intermediate space 50 delimited by a portion of the inner ferrule, for example the portion provided with the inlet orifice 27, a portion of the outer part 140, for example the outer ferrule 14 on the one hand and by an upstream flange 16 and downstream flange 18 on the other hand.

[0054] The two ferrules, for example coaxial annular ferrules, respectively internal 12 and external 14, can be mutually connected by the two flanges, for example transverse ferrules, respectively upstream 16 and downstream 18.

[0055] The upstream flange 16 can be arranged downstream of a low pressure compressor 20 of the turbomachine while the downstream flange 18 can be arranged upstream of the high pressure compressor 22 of this turbomachine.

[0056] The downstream transverse flange 18 may include a portion which may be provided with one or more air passage orifices 40 called intermediate orifices. The downstream transverse flange 18 may be arranged so that the intermediate orifices 40 are arranged, for example, respectively downstream of each of the discharge valves 30 and positioned, for example, near the primary flow space 24, for example radially at the same level as the inlet orifices 27 of these discharge valves 30.

[0057] The discharge vein conduit 44 may, for example, include a first end portion 442, comprising, for example, an inlet 4420 of the conduit, which may be connected to the downstream transverse flange 18, for example, fixed to the flange, for example, to the portion of the flange provided with the intermediate ports. The discharge vein conduit 44 may, for example, include a second end portion 444, comprising, for example, an outlet 4440 of the conduit, which may be connected to the external part 140, for example, fixed to the external part 140, for example, to the portion of the external part 140, for example, the outer ferrule 14 and / or the annular wall 36 of the extension 38 provided with the outlet ports 42.

[0058] The discharge vein conduit 44, which can be configured to guide an airflow F3 from the primary flow space to the secondary flow space, can extend from the downstream transverse flange 18 to the external part 140, for example to the annular wall 36 of the extension 38.

[0059] Thus the discharge vein duct can be configured to guide the airflow from the primary flow space, from the intermediate space to the secondary flow space.

[0060] The discharge vein conduit 44 can open into the intermediate space 50, for example at the upstream surface of the downstream transverse flange 18 comprising said intermediate orifices 40 and on the other hand, into the secondary flow space, for example through said outlet orifices 42.

[0061] The discharge vein conduit 44 allows air to be guided between the intermediate orifices 40 of the downstream transverse flange 18 and the corresponding orifices 42 provided in the outer ferrule 14 or the annular wall 36 of the extension 38 of the hub 10, the conduit 44 mutually connecting these intermediate and outlet orifices 40 and 42. The conduit 40 can be bent to reduce its axial size, as in [Fig.3].

[0062] When the airflow F3 drawn from the first flow space 24 passes through the intermediate cavity 50 before being reinjected, for example, into the second flow space 32, the walls of the flange, for example, the downstream transverse flange 18, can generate pressure losses. Indeed, although part of the airflow F3 drawn from the first flow space 24 finds its way to the inlet 4420 of the discharge duct in the downstream transverse flange 18, part of this airflow F3 may strike said flange 18. This generates pressure losses, due in particular to the contact between the airflow F3 from the valve 30 and the downstream transverse flange 18, and also reduces the efficiency of the discharge ducts.

[0063] In order to prevent this pressure loss, the hub according to the present invention includes the suction device 700 configured to suction the airflow F3 from the first flow space 24, into the discharge vein duct 44, 440.

[0064] In particular, the suction device 700 is configured to suction the airflow from the intermediate space 50, coming from the first flow space 24 for example via the discharge valve 30, into the discharge vein duct 44, 440.

[0065] The suction device 700 according to the invention makes it possible to suction the air contained in the intermediate space 50 in order to ensure the evacuation of the entire volume of air taken from the first flow space to the second flow space 32 via the discharge vein conduit.

[0066] The suction device 700 can be configured to be selectively activated or deactivated so as to respectively draw in air or cease drawing in airflow, depending on the need. The suction device 700 can be an active suction device. The hub can further include an activation / deactivation device 800 configured to selectively activate and / or deactivate the suction device 700. The activation / deactivation device 800 can further include a power source configured to supply power to the suction device when it is activated, and to which the suction device can be connected. The activation / deactivation device 800 can, for example, include a motor, such as an electric or internal combustion engine.

[0067] The suction device 700 can be arranged in the discharge vein 40, 440.

[0068] This configuration makes it possible to provide a space-saving and more compact solution.

[0069] For example, the suction device 700 can be arranged in the end portion, for example, upstream 442 of the discharge vein conduit, which is for example connected to the downstream transverse flange 18.

[0070] For example, the suction device 700 can be arranged in the inlet 4420 of the discharge vein conduit.

[0071] For example, the suction device 700 comprises a plurality of movable blades rotating around an axis (Figures 5 and 6).

[0072] For example, the suction device 700 may include a propeller 760.

[0073] In this case, the suction device can also be configured to put actively rotates the airflow from the first flow space into the discharge vein duct.

[0074] The device can thus, for example by means of the propeller, be configured to both Air is drawn into the duct, and the incoming airflow is rotated, for example, actively (the propeller can be rotated using the on / off switch 800). Rotating the airflow F3 allows its velocity to be adjusted, limiting its normal velocity relative to the second airflow F2 exiting the discharge duct. This facilitates redirecting the airflow F3 from the primary flow space Fl and aligning it as closely as possible with the secondary flow F2, i.e., substantially parallel to and in the same direction as the second airflow F2, when the airflow F3 is reinjected into the second flow space.Indeed, since the reinjection angle at the duct outlet is a function of the reinjection velocity, in order to reduce the angle, it is necessary to decrease the velocity of the airflow F3 at the duct outlet, i.e., to increase the diffusivity of the airflow F3 relative to the secondary flow.

[0075] The suction device 700 can be adapted to the already known conduits as can be seen in Figures 1 and 3. Alternatively, the hub can include an alternative discharge vein conduit 440 according to the invention as illustrated in Figures 5, 6, 7a, 7b, 8a and 8b.

[0076] As illustrated in these figures, this discharge vein conduit 440 can also be bent but can also be cylindrical, for example have a circular section 446, for example over its entirety, that is to say that the entire conduit can be cylindrical.

[0077] Thanks to the cylindrical shape of the duct, the rotational movement given to the airflow when it enters the duct, by the propeller, is ensured to be maintained within the circular section duct until the exit of the duct.

[0078] The proposed solution makes it possible, on the one hand, to draw in the air contained in the intermediate space in order to ensure the evacuation of the entire volume of air extracted through the valve(s) to the second flow space. Air intake can be achieved by a propeller located, for example, at the duct inlet. Furthermore, the air drawn in by the propeller can be set in rotation. This rotational motion is maintained within the circular cross-section tube. The solution also allows for the dissipation of the air exiting the duct into the second flow, thanks to the rotation of the extracted air, via the combination of the duct and the propeller. Once rotated, the radial and axial components of the flow velocity are transformed into a tangential component (via the rotation of the F3 flow), which facilitates the diffusivity of the F3 flow exiting the duct.

[0079] Fig. 4 illustrates the operating principle.

[0080] When the airflow F3 is drawn in through the gate 28, 30, it is drawn, for example, from the intermediate space 50 by the suction device 700 into the duct 44, 440. The principal velocity components are axial and radial. By rotating the airflow F3 in the duct, for example at the inlet of the duct 442, for example by means of the propeller, the principal velocity components then become tangential. The cylindrical duct, for example with a circular cross-section 446, maintains the tangential velocity until the duct outlet. The outlet 440 of the duct can be optimized. This rotation of the airflow F3 allows the velocity of the airflow F3 to be adjusted by limiting the normal velocity of the airflow F3 relative to the second airflow F2 at the outlet of the discharge duct.This allows participation in a redirection of the airflow F3 from the primary flow space Fl and aligning it as much as possible with that of the secondary flow F2 at the outlet of the duct, that is to say substantially parallel to the second airflow F2 and in the same direction as the second airflow F2, when the airflow F3 is reinjected into the second flow space 32.

[0081] In order to maximize the effect of rotating the airflow F3 taken from the first flow space and reinjected into the second flow space, the hub may include a rotation device 600, for example complementary, configured to rotate the airflow F3 from the first flow space in the discharge vein duct, for example passively.

[0082] The additional rotation device can be a passive rotation device, that is to say, it does not require an external power source such as a motor to operate.

[0083] The rotation device 600 can for example be arranged in the discharge vein conduit 44, for example inside the discharge vein conduit 44.

[0084] This configuration makes it possible to provide a less bulky and more compact solution than the solutions proposed in the prior art such as the use of grids or fins.

[0085] For example, the rotation device can be arranged in the upstream end portion of the discharge vein conduit, for example at the inlet of the discharge vein conduit. When the hub comprises a plurality of conduits, the hub can comprise a plurality of rotation devices. Each rotation device can be arranged respectively in at least one upstream end portion of one of the conduits.

[0086] The rotation device 600 may, for example, have a cross-section 6000, for example internal. The cross-section may have at least one channel, for example one or more channels, for example rotation. The at least one channel, for example at least one groove and / or at least one thread, forms an airflow guide channel so as to rotate it and / or to contribute to the rotation of the airflow. The at least one channel may be at least one groove.

[0087] Section 6000 can in particular be a grooved and / or threaded section 6000 ([Fig.6], 7a, 7b, 8a and 8b), for example grooved and / or threaded internally.

[0088] The internal section may be a helical section 6000, for example, such as to present a section extending helically in the direction of the airflow. Such an internal section shape may allow and / or facilitate the rotation of the airflow.

[0089] For example, the rotation device 600 can be stationary relative to the discharge vein conduit 440.

[0090] The rotating device 600, for example the internal section 6000, may, for example, have at least one channel, for example a groove and / or a thread 640, for example a helical channel, for example a helical groove and / or a helical thread 640 (screw pitch). The channel, for example the groove and / or thread 640, may be an internal channel, for example an internal groove and / or internal thread. The internal channel, for example an internal groove and / or internal thread, may be arranged in the discharge channel 44, for example on an internal wall of the discharge channel 440, for example extending along the internal wall of the discharge channel 440, for example an internal wall of the upstream portion 442 of the discharge channel 440. For example the channel, for example the grooving and / or the threading, for example helical, can extend over the upstream portion 442 of the conduit only.

[0091] Alternatively, the section having at least one channel, for example the grooved and / or threaded section, for example helical, for example the channel, for example the grooving and / or threading, for example helical 640, can extend over the entire, by For example, the entire internal wall of the discharge vein conduit 440, for example from the upstream portion 442 to the downstream portion 444 of the conduit 440. This helps to limit pressure losses.

[0092] The width of the groove, for example of the groove(s) forming the groove, may be less than, for example reduced compared to, the depth of the groove, for example of the groove(s) forming the groove. The thread may, for example, have a narrow shape that may be conducive to the rotation of certain airflows.

[0093] The groove, for example helical, is such that the groove(s) forming the groove have dimensions less than, for example reduced in relation to, the surface area of ​​the wall containing the groove, i.e., for example, the cross-section of the internal wall of the discharge conduit 440 over which the groove extends, for example the entire cross-section and / or a portion thereof. The groove, for example helical, is such that the groove(s) forming the groove extend over less than half the surface area of ​​the wall containing the groove. The wall containing the groove may comprise, for example, a first part occupied by the groove and a second part complementary to the first part, the second part being without a groove.The grooving, for example helical, can be such that the first part occupies a surface area smaller than the surface area of ​​the second part, the surface area being, for example, a projected surface and / or a convex envelope surface of the wall. The grooving, for example helical, is such that the groove(s) forming the grooving have a width less than, for example reduced compared to, the width of the second part.

[0094] The depth of the thread, for example of the thread(s) forming the thread, may be less than, for example reduced compared to, the width of the thread, for example of the thread(s) forming the thread. The thread may, for example, have a flared shape which may be conducive to the rotation of certain airflows.

[0095] The thread, for example helical, is such that the thread(s) forming the thread have dimensions greater than the surface of the wall containing the thread, i.e., for example, the cross-section of the internal wall of the discharge conduit 440 over which the thread extends, for example, the entire cross-section and / or a portion thereof. The thread, for example helical, is such that the surface of the wall containing the thread has dimensions reduced compared to the thread(s) forming the thread. The thread, for example helical, is such that the thread(s) forming the thread extend over half or more of the surface of the wall containing the thread. The wall containing the thread may comprise, for example, a first part occupied by the thread and a second part complementary to the first part, the second part being without thread. The thread, by A helical thread, for example, can be such that the first part occupies a surface area greater than or equal to the surface area of ​​the second part, the surface area being, for example, a projected surface and / or a convex hull surface of the wall. A helical thread, for example, can be such that the thread(s) forming the thread have a width greater than, for example, extended relative to, the width of the second part. A helical thread, for example, can also be such that the width of the second part is reduced relative to the width of the thread(s) forming the thread.

[0096] The width and / or depth of the channel, for example of the groove and / or thread, can change in the direction of the airflow.

[0097] The rotation device can thus be configured so that the shape of the duct causes the airflow to rotate.

[0098] The advantages of the invention are to allow the aspiration of air from the valves so that the pressure loss between the valve and the duct is minimized and controlled, to reduce the pressure losses in the duct thanks to the cylindrical shape (circular section), to increase the diffusivity of the flow at the outlet of the duct by rotating the flow in the duct in order to limit the impact on the operability of the surrounding parts, and to optimize the reinjection of air at the outlet of the duct.

[0099] This solution ensures maximum efficiency on any sampling system while limiting the impacts during the reintroduction of air at the sampling outlet.

[0100] This solution can be applied to all engine components requiring air intake or reinjection.

[0101] Depending on the surrounding physical parameters, the dimensions of the ducts can be adapted. The propeller characteristics (diameter, number of blades, positioning, etc.) can be chosen accordingly. Similarly, the length, shape, and cross-section of the duct can be modified according to the need and available space.

Claims

1.

2. Demands Intermediate housing hub (10) for an aircraft turbomachine, said hub (10) comprising: - an internal shell (12) configured to delimit a first flow space (24) for a first flow (Fl) of air from the turbomachine, the internal shell (12) comprising at least a portion provided with at least one air passage orifice (27), called the inlet orifice, - at least one discharge valve (30) comprising a movable flap (28) between an open position and a closed position of said inlet orifice (27), - an external part (140) configured to delimit a second flow space (32) for a second air flow (F2) from the turbomachine, the external part (140) comprising at least one portion provided with at least one air passage orifice (42), called an outlet orifice, - a discharge duct (44, 440), the duct (44, 440) being configured to guide an airflow (F3) from the first flow space (24) to the second flow space (32), - a suction device (700), for example active, configured to suction the airflow (F3) from the first flow space (24), into the discharge vein duct (44, 440). Intermediate housing hub (10) according to claim 1, the hub (10) comprising: - an intermediate space (50), delimited by the portion of the inner ferrule (12) provided with said inlet orifice (27), a portion of the outer part (140), a first upstream flange (16) and a second downstream flange (18), in which the conduit (44, 440) opens on one side into the intermediate space (50) and on the other side into the second flow space (32), and in which the suction device (700) is configured to suction the airflow (F3) from the intermediate space (50) into the discharge vein conduit (44, 440).

3. Intermediate housing hub (10) according to any one of the preceding claims wherein the suction device (700) is arranged in the discharge vein conduit (44, 440).

4. Intermediate housing hub (10) according to any one of the preceding claims wherein the suction device (700) is arranged in an upstream end portion (442) of the discharge vein conduit (44, 440).

5. Intermediate housing hub (10) according to any one of the preceding claims wherein the suction device (700) comprises a propeller (760) comprising a plurality of blades movable and rotating about an axis.

6. Intermediate housing hub (10) according to any one of the preceding claims wherein the discharge vein conduit (440) is cylindrical.

7. Intermediate housing hub (10) according to any one of the preceding claims wherein the hub (10) includes a rotation device (600), for example passive, configured to rotate the airflow (F3) from the first flow space (24) in the discharge vein conduit (44, 440).

8. Intermediate housing hub (10) according to the preceding claim in which the rotation device (600) has at least one channel, for example a groove and / or a thread (640), for example an internal channel, for example an internal groove and / or internal thread, arranged in the discharge vein conduit (44, 440).

9. Intermediate housing hub (10) according to the preceding claim in which the internal channel, for example the internal groove and / or internal thread is a helical channel, for example a helical groove and / or a helical thread.

10. Aircraft turbomachine (2) comprising an intermediate casing (11) for an aircraft turbomachine comprising a hub (10) according to any one of the preceding claims.

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