RECTIFIER BLADE FOR TURBOMACHINE COMPRESSOR, COMPRESSOR AND ASSOCIATED TURBOMACHINE

Abstract

The invention relates to a straightening blade (2, 2', 2'', 2''') for a turbomachine compressor (12), said straightening blade comprising: an internal platform (21, 21', 21'', 21''') intended to internally delimit a primary flow channel intended to supply a combustion chamber; at least one blade (20, 20', 20'', 20''') extending radially outwards from said internal platform (21, 21', 21'', 21''');a foot extending radially inwards from the inner platform and having a sealing wall (23, 23', 23'', 23''') extending radially opposite the inner platform (21, 21', 21'', 21''') on the side opposite the blade (20, 20', 20'', 20''') and intended to form, with a compressor rotor shaft (6), a rotating seal intended to limit the flow of recirculated air from a downstream region (91) of the primary flow path defined downstream of the stator blade (2, 2', 2'', 2''') to an upstream region (90) of the primary flow path defined upstream of the stator blade (2, 2', 2'', 2'''); the foot comprising a connecting wall (22, 22', 22'', 22''') connecting said internal platform (21, 21', 21'', 21''') to said sealing wall (23, 23', 23'', 23''') and having an upstream surface and a downstream surface;characterized in that said straightening blade (2, 2', 2'', 2''') comprises means for limiting an injection of said recirculation flow radially from the inside into said upstream region (90) of the primary flow channel. Figure 4.;

Description

Title of the invention: RECTIFIER BLADE FOR TURBOMACHINE COMPRESSOR, ASSOCIATED COMPRESSOR AND TURBOMACHINE Field of invention

[0001] The present invention relates to the field of turbomachines such as turbopropellers or turbojets.

[0002] More particularly, the invention relates to the field of axial turbomachine compressors and more precisely concerns a stator vane for a compressor. State of the prior art

[0003] A turbomachine compressor, which may be a low-pressure or high-pressure compressor, comprises an alternation of rotor blades connected to each other by a common compressor rotor shaft, and stator rectifier blades secured to a compressor casing, the compressor casing externally delimiting a primary flow stream intended to supply a combustion chamber.

[0004] Such an example of a turbomachine compressor is for example presented in patent FR 2 999 249.

[0005] In low pressure or high pressure compressors, the rectifier blades make it possible to divert the air flow coming from the rotor blade directly upstream of the rectifier blade, and therefore to straighten the primary flow leaving the rotor blade upstream, in order to increase the static pressure of this air flow, to control the incidence of this air flow on the following rotor blade and thus to improve the efficiency of the compressor.

[0006] Due to the speeds flowing in each of the rectifier blades, the static pressure downstream of a given rectifier blade is higher than that upstream. This pressure difference between the upstream of the rotor blade and the downstream of the rotor blade results in a recirculation flow radially under the rectifier blade.

[0007] It is known to implement a sealing wall extending at the level of the rectifier blade and intended to form, with the compressor rotor shaft, a rotating seal intended to limit the flow of an air recirculation flow from a downstream region of the primary flow stream defined downstream of the rectifier blade to an upstream region of the primary flow stream defined upstream of the rectifier blade.

[0008] However, and due to the permeability of this seal combined with the difficulty of implementing a tight clearance between the rectifier vane and the rotor shaft compressor, there remains a recirculation flow at the level of a space radially formed under the rectifier blade.

[0009] A disadvantage of such a recirculation flow is that it does not work in the compressor suite which inevitably impacts the compressor efficiency.

[0010] Furthermore, another disadvantage of such a recirculation flow is that it can reintroduce itself into the heart of the primary flow stream, for example at the base of the blades of the vanes, and therefore cause separations of the primary flow, thus impacting the operation of the compressor.

[0011] Yet another disadvantage is that this recirculation flow is heated because it passes through stator elements and rotor elements. As a result, by recirculating, this recirculation flow causes energy losses through heating. Furthermore, this recirculation flow also causes heating of the various parts that it passes through, which can be detrimental to the proper operation of the compressor.

[0012] There is therefore a need to provide another solution making it possible to limit the recirculation flow of the primary flow circulating in a compressor, or at the very least to better distribute the recirculation at the level of the rectifier blade. Statement of the invention

[0013] The invention aims to remedy at least in part the drawbacks mentioned above relating to the techniques of the prior art.

[0014] To this end, the invention relates to a rectifier blade for a turbomachine compressor, said rectifier blade comprising: - an internal platform intended to internally delimit a primary flow vein intended to supply a combustion chamber; - at least one blade extending radially outward from said internal platform; - a root which extends radially inward from the internal platform and which has a sealing wall extending radially opposite the internal platform radially on the side opposite the blade and intended to form, with a compressor rotor shaft, a rotating seal intended to limit the flow of an air recirculation flow from a downstream region of the primary flow path defined downstream of the rectifier blade to an upstream region of the primary flow path defined upstream of the rectifier blade; - the foot comprising a connecting wall connecting said internal platform to said sealing wall and having an upstream surface and a downstream surface.

[0015] According to the invention, said rectifier vane comprises means for limiting a

[0016]

[0017]

[0018]

[0019]

[0020]

[0021]

[0022]

[0023]

[0024] injecting said recirculation flow radially from the inside into said upstream region of the primary flow stream, said means comprising at least one of: - an air sampling channel, having an air intake opening through at least one of a radially internal surface of the internal platform and said upstream and downstream surfaces of the connecting wall, and an air outlet opening through a region of the blade distant from the internal platform; and - a pressure balancing configuration, in which said connecting wall connects a downstream end of said internal platform to a downstream end of said sealing wall so that the connecting wall, the internal platform and the sealing wall delimit an internal C-section rectifier cavity opening upstream of said rectifier vane. Thus, the invention proposes an approach making it possible to resolve at least in part certain of the drawbacks of the prior art. In particular, by implementing means for limiting an injection of said recirculation flow radially from the inside into said upstream region of the primary flow stream, the recirculation flow is controlled so as to prevent it from reintroducing itself into the heart of the primary flow stream and causing separations of the primary flow. Furthermore, by reintroducing the recirculation flow in a controlled manner, the compressor efficiency is improved. Furthermore, the heating of the various rooms is limited by controlling the path taken by the recirculation flow as well as the quantity of recirculation flow. According to a particular aspect of at least one embodiment of the invention, said air outlet opens onto an upstream face of said blade, close to a radially external edge of said blade. This makes it possible to reinject the recirculation air flow into an area of ​​the flow vein at the edge of the flow vein of the primary flow, thus not disturbing or only slightly disturbing the flow of the primary flow in the flow vein. According to a particular aspect of at least one embodiment of the invention, said air outlet is provided on a radially external end of said blade so as to be able to open into a formed air reinjection passage which extends into a casing of said compressor. This allows the recirculation airflow to be redirected away from the primary flow path and reinjected upstream of the compressor. According to a particular aspect of at least one embodiment of the invention, said internal platform has an upstream end extending axially upstream of said blade.

[0025] Such an outgrowth extending into the upstream region, out of the primary flow stream, thus makes it possible to guide the recirculation flow towards the internal cavity of the C-section rectifier.

[0026] The invention also relates to a turbomachine compressor comprising at least: - a casing which extends around so as to radially externally delimit a flow vein of a primary flow intended to supply a combustion chamber; - a compressor rotor shaft; - a rectifier vane according to one of the aforementioned embodiments; - an upstream rotor blade arranged upstream of said rectifier blade, said rectifier vane and said upstream rotor vane delimiting an upstream region of said primary flow stream, said upstream rotor vane comprising: • an internal platform intended to radially internally delimit said primary flow stream intended to supply a combustion chamber; • a blade extending radially outward from said internal platform; • a connecting wall connecting said internal platform to said compressor rotor shaft and having an upstream surface and a downstream surface; - a downstream rotor blade arranged downstream of said rectifier blade, said rectifier blade and said downstream rotor blade delimiting a downstream region, said downstream rotor blade comprising: • an internal platform intended to radially internally delimit said primary flow stream intended to supply a combustion chamber; • a blade extending radially outward from said internal platform; • a connecting wall connecting said internal platform to said compressor rotor shaft and having an upstream surface and a downstream surface.

[0027] According to a particular aspect of at least one embodiment of the invention, the downstream rotor blading further comprises a pressure balancing configuration in which said connecting wall of the downstream rotor blading connects a downstream end of said internal platform of the downstream rotor blade to said compressor rotor shaft such that said compressor rotor shaft and said connecting wall of the downstream rotor blade and internal platform of the downstream rotor blade delimit an internal cavity of the downstream rotor blade with a C-shaped section opening towards the upstream of said downstream rotor blade.

[0028] Such a C-shaped cavity opening upstream of the downstream rotor blade thus makes it possible to trap part of the recirculation air flow and thus to form a vortex in this cavity. This makes it possible to better control the positioning of the vortices in the downstream region.

[0029] According to a particular aspect of at least one embodiment of the invention, said internal platform of the downstream rotor blade has an upstream end extending axially upstream of said blade of the downstream rotor blade.

[0030] Such an outgrowth extending into the downstream region thus makes it possible to increase the rotor surface in contact with the recirculation air flow, and therefore to reduce the pressure of this recirculation air flow, and consequently the recirculation flow rate.

[0031] According to a particular aspect of at least one embodiment of the invention, the compressor comprises an annular tooth arranged on the external periphery of the rotor shaft of the compressor, axially substantially aligned with said upstream end of the internal platform of the downstream rotor blade.

[0032] According to a particular aspect of at least one embodiment of the invention, the upstream rotor blading comprises an annular wall formed from a downstream end of said internal platform of the upstream rotor blading and extending radially between said compressor rotor shaft and said internal platform of the upstream rotor blading.

[0033] Such an annular wall which consists of a rectilinear surface coming into alignment with the downstream edge of the upstream rotor blading thus makes it possible to reduce the contact surface between the upstream rotor blading and the recirculation flow.

[0034] The invention also relates to a turbomachine for an aircraft, in particular a turbojet, comprising a compressor according to one of the aforementioned embodiments. Presentation of the figures

[0035] The invention, as well as the various advantages that it presents, will be more easily understood in the light of the following description of an illustrative and non-limiting embodiment thereof, and of the appended drawings among which: [Fig.l] is a schematic sectional view of a turbomachine; [Fig.2] is a schematic sectional view of a part of a compressor according to a first embodiment of the invention; [Fig.3] is a schematic sectional view of part of a compressor according to a second embodiment of the invention; [Fig.4] is a schematic sectional view of a part of a compressor according to a third embodiment of the invention, and [Fig.5] is a schematic sectional view of a part of a compressor according to a fourth embodiment of the invention.

[0036] Detailed description of an embodiment of the invention

[0037] It should be noted that the invention applies to any type of turbomachine, and in particular to aircraft turbomachines.

[0038] This turbomachine 10, which extends along an axis X, is for example intended to be mounted on an aircraft (not shown), such as an airplane or a helicopter, for example under the wing of the aircraft, on the wing or even at the rear of the fuselage of the aircraft.

[0039] [Fig.l] illustrates a turbomachine 10, for example a twin-spool, dual-flow turbojet engine for aircraft, generally comprising a fan 11 intended for the suction of an air flow F1 dividing downstream of the fan into a primary flow F2 circulating in a primary flow channel, hereinafter referred to as the primary flow path PV, and a secondary flow F3 circulating in a secondary flow channel, hereinafter referred to as the secondary flow path SV, arranged around the primary flow path PV.

[0040] The turbomachine generally comprises a low pressure compressor 12, a high pressure compressor 13, a combustion chamber 14, a high pressure turbine 15 and a low pressure turbine 16 which jointly define the primary stream PV.

[0041] The respective rotors of the high pressure compressor and the high pressure turbine are connected by a shaft called a "high pressure shaft", while the respective rotors of the low pressure compressor and the low pressure turbine are connected by a shaft called a "low pressure shaft", in a well-known manner. These rotors are rotatably mounted around an axis 100 of the turbomachine.

[0042] Throughout this description, the axial direction X is the direction of the axis 100. The radial direction R is at all points a direction orthogonal to the axis 100 and passing through the latter, and the orthoradial or circumferential direction C is at all points a direction orthogonal to the radial direction R and to the axis 100. A transverse plane is a plane orthogonal to the axis 100. The terms “internal” and “external” refer respectively to a relative proximity, and a relative distance, of an element with respect to the axis 100. Finally, the “upstream” and “downstream” directions are defined with reference to the general direction of the flow of gases in the primary PV and secondary SV veins of the turbomachine, in the axial direction X.

[0043] The general principle of the invention is based on the implementation of a turbomachine compressor comprising a rectifier blade comprising means for limiting an injection of the recirculation flow radially from the inside into the upstream region of the primary flow vein, which comprise at least one of: - at least one air sampling channel, having an air intake opening through at least one of a radially internal surface of the internal platform and the upstream and downstream surfaces of the connecting wall, and an air outlet opening through a region of the blade distant from the internal platform; and - a pressure balancing configuration, in which the connecting wall connects a downstream end of the internal platform to a downstream end of the sealing wall so that the connecting, internal and sealing walls delimit an internal C-section rectifier cavity opening upstream of the rectifier blade.

[0044] We now present, in relation to [Fig.2], a turbomachine compressor according to a first embodiment of the invention.

[0045] As illustrated in this [Fig.2], the turbomachine compressor 12 comprises: - a casing 5 which extends peripherally so as to radially, externally delimit a flow vein of a primary flow intended to supply a combustion chamber; - a compressor rotor shaft 6; - a rectifier vane 2; - an upstream rotor blade 3 arranged upstream of the rectifier blade 2, the rectifier blade 2 and the upstream rotor blade 3 delimiting an upstream region 90 of the primary flow stream; - a downstream rotor blade 4 arranged downstream of the rectifier blade 2, the rectifier blade 2 and the downstream rotor blade 4 delimiting a downstream region 91.

[0046] The upstream rotor blade 3 comprises: - an internal platform 31, otherwise called an upstream internal platform, intended to radially, internally delimit the primary flow stream intended to supply a combustion chamber; - a blade 30, otherwise called an upstream blade, extending radially outwards from the internal platform 31; - a connecting wall 32, otherwise called an upstream connecting wall, connecting the internal platform 31 to the compressor rotor shaft 6 and having an upstream surface and a downstream surface;

[0047] As for the downstream rotor blade 4, it comprises: - an internal platform 41, otherwise called a downstream internal platform, intended to radially internally delimit the primary flow stream

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

[0054] intended to supply a combustion chamber; - a blade 40, otherwise called a downstream blade, extending radially outwards from the internal platform 41; - a connecting wall 42, otherwise called a downstream connecting wall, connecting the downstream internal platform 41 to the compressor shaft 6 and having an upstream surface and a downstream surface. In this embodiment, and as illustrated, the rectifier vane 2 comprises: - an internal platform 21 intended to internally delimit the primary flow stream intended to supply a combustion chamber; - a blade 20 extending radially outwards from the internal platform 21; - a foot which extends radially inwards from the internal platform and which has a sealing wall 23 extending opposite the internal platform 21 radially on the side opposite the blade 20 and intended to form, with the compressor rotor shaft 6, a rotating seal intended to limit the flow of an air recirculation flow from the downstream region 91 to the upstream region 90 of the primary flow stream; - a connecting wall 22 connecting the internal platform 21 to the sealing wall 23 and having an upstream surface and a downstream surface; To form the rotating seal, the compressor rotor shaft 6 here comprises wipers 60, while the sealing wall 23 comprises an abradable element, such as an abradable track, mounted opposite these wipers 60. According to the invention, the rectifier vane 2 comprises means for limiting an injection of the recirculation flow radially from the inside into the upstream region 90 of the primary flow stream which take the form, in this embodiment, of an air sampling channel 24. As can be seen, in this embodiment, the air sampling channel 24 has an air inlet 240 opening through the downstream surface of the connecting wall 22, and an air outlet 241 opening through a region of the blade 20 distant from the internal platform 21. More particularly, in this embodiment, the air outlet 241 opens onto an upstream face of the blade 20, close to a radially external edge of the blade 20. As a result, the air flow is reinjected into the upstream region 90 of the primary flow path, close to the radially outer edge of the blade 20. In fact, the closer the air outlet is to the radially external edge of the blade, the less the air recirculation flow will disturb the flow of the primary flow because it will remain substantially at the end of this flow.

[0055] Furthermore, and as visible in [Fig.2], the air intake 240 opens through the downstream surface of the connecting wall 22 in the vicinity of the internal platform 21.

[0056] Therefore, in the embodiment, the air intake is carried out before the recirculation flow passes through the rotating seal so that only a portion of the recirculation flow passes through this rotating seal.

[0057] We now present, in relation to [Fig. 3], a turbomachine compressor according to a second embodiment of the invention.

[0058] In this embodiment, the upstream rotor blading 3 and the downstream rotor blading 4 are identical to the upstream and downstream rotor bladings of the first embodiment illustrated in [Fig.2], and only the rectifier blading differs.

[0059] In this second embodiment, and as illustrated in [Fig.3], the rectifier blade 2' comprises: - an internal platform 21' intended to radially internally delimit the primary flow stream intended to supply a combustion chamber; - a blade 20' extending radially outward from the internal platform 21'; - a foot which extends radially inwards from the internal platform and which has a sealing wall 23' extending opposite the internal platform 21' on the side opposite the blade 20' and intended to form, with the compressor rotor shaft 6, a rotating seal intended to limit the flow of an air recirculation flow from the downstream region 91 to the upstream region 90 of the primary flow stream; - a connecting wall 22' connecting the internal platform 21' to the sealing wall 23' and having an upstream surface and a downstream surface;

[0060] To form the rotating seal, and as for the first embodiment, the compressor shaft 6 here comprises wipers 60, while the sealing wall 23' comprises an abradable element mounted radially opposite these wipers 60.

[0061] In this embodiment, the rectifier vane 2' comprises means for limiting an injection of the recirculation flow radially from the inside into the upstream region 90 of the primary flow stream which take the form, in this embodiment, of an air sampling channel 24'.

[0062] As can be seen, in this embodiment, the air sampling channel 24' has an air inlet 240' opening through the upstream surface of the connecting wall 22', and an air outlet 241' opening through a region of the blade 20' distant from the internal platform 21'.

[0063] More particularly, in this embodiment, the air outlet 241' is provided on a radially external end of the blade 20' so as to open into an inlet of an air reinjection passage 50 which extends into the casing 5 of the compressor 12, external to the flow stream.

[0064] As a result, the air flow is reinjected upstream of the compressor 12, which makes it possible to improve the efficiency of such a compressor.

[0065] Furthermore, and as visible in [Fig. 3], the air intake 240' opens through the upstream surface of the connecting wall 22' in the vicinity of the internal platform 21'.

[0066] Therefore, in the embodiment illustrated in [Fig.3], the air intake is carried out after the recirculation flow has passed through the rotating seal.

[0067] We now present, in relation to [Fig.4], a turbomachine compressor according to a third embodiment of the invention.

[0068] In this third embodiment, the 2” rectifier vane comprises: - an internal platform 21” intended to internally delimit the primary flow stream intended to supply a combustion chamber; - a 20” blade extending radially outward from the 21” internal platform; - a foot which extends radially inwards from the internal platform and which has a sealing wall 23” extending opposite the internal platform 21” on the side opposite the blade 20''; - a connecting wall 22'' connecting the internal platform 21” to the sealing wall 23” and having an upstream surface and a downstream surface;

[0069] In this embodiment, the means for limiting an injection of said recirculation flow radially from the inside into the upstream region 90 of the primary flow stream comprise an air sampling channel 24”.

[0070] As can be seen, in this embodiment, the air sampling channel 24'' has an air inlet 240" opening through a radially internal surface of the internal platform 21", and an air outlet 241" opening through a region of the blade 20" distant from the internal platform 21".

[0071] More particularly, in this embodiment, the air outlet 241” is arranged on a radially external end of the blade 20” so as to open into an inlet of an air reinjection passage 50 which extends into the casing 5 of the compressor 12, external to the flow stream.

[0072] Furthermore, in this embodiment, the means for limiting an injection of said recirculation flow radially from the inside into the upstream region 90 of the primary flow stream comprise, in this embodiment, a pressure balancing configuration, in which the connecting wall 22” connects a downstream end of the internal platform 21” to a downstream end of the wall sealing 23” so that the connecting walls 22”, inner 21” and sealing 23” delimit an internal cavity 7 of the rectifier with C-section opening upstream of the rectifier blade 2”.

[0073] Such an internal cavity makes it possible to trap part of the air flow and therefore to better control the vortex formation zones downstream of the rectifier blade.

[0074] As visible in [Fig.4], the internal platform 21” also has an upstream end extending axially upstream of the blade 20”.

[0075] In other words, the internal platform 21” has an upstream end formed as an annular projection from an edge of the rectifier blade.

[0076] Such an outgrowth extending into the upstream region, out of the primary flow stream, thus makes it possible to guide the recirculation flow towards the internal cavity of the C-section rectifier.

[0077] In this third embodiment, the downstream rotor blade 4' also comprises a pressure balancing configuration in which the connecting wall 42' of the downstream rotor blade 4' connects a downstream end of the internal platform 41' of the downstream rotor blade 4' to the compressor shaft 6 so that the compressor shaft 6 and the connecting walls 42' of the downstream rotor blade 4' and internal platform 41' of the downstream rotor blade 4' delimit an internal cavity 8 of the downstream rotor blade with a C-shaped section opening towards the upstream of the downstream rotor blade 4'.

[0078] Such an internal cavity provided at the level of the downstream rotor blade 4' makes it possible to trap part of the air flow and therefore to better control the vortex formation zones upstream of the rectifier blade.

[0079] In a similar manner to the internal cavity 7 of the rectifier blade, the internal platform 41' of the downstream rotor blade 4' here has an upstream end extending axially upstream of the blade 40' of the downstream rotor blade 4'.

[0080] Such an outgrowth extending into the downstream region, out of the primary flow path, thus makes it possible to guide the recirculation flow towards the internal C-section cavity of the downstream rotor blade.

[0081] Here, the compressor further comprises an annular tooth 44' arranged on the external periphery of the compressor rotor shaft 6, and which is axially substantially aligned with the upstream end of the internal platform 41' of the downstream rotor blade 4'.

[0082] In this way, this makes it possible to slightly close the contour of the internal cavity 8 to better control the vortex which forms in this internal cavity 8.

[0083] Furthermore, in this embodiment, the upstream rotor blade 3' comprises an annular wall 35 formed from a downstream end of the internal platform 31' of the upstream rotor blade 3' and extending radially between the compressor shaft 6 and the 31' internal platform of the 3' upstream rotor blade.

[0084] This annular wall 35 makes it possible to reduce the contact surface between the recirculation flow and the upstream rotor blading, at the exit of the seal. It also makes it possible to form a protection of the upstream rotor blading against potential heating by contact with the recirculation flow arriving in the upstream region 90.

[0085] As with the internal cavity of the downstream rotor blade, or downstream rotor, such an internal cavity provided at the level of the upstream rotor blade, or upstream rotor, makes it possible to trap part of the air flow and therefore to better control the vortex formation zones upstream of the rectifier blade.

[0086] We now present, in relation to [Fig.5], a turbomachine compressor according to a fourth embodiment of the invention.

[0087] In this fourth embodiment, the 2”' rectifier blade comprises: a 21'” internal platform intended to internally delimit the primary flow vein intended to supply a combustion chamber; a 20”' blade extending radially outward from the 21”' inner platform; a foot which extends radially inwards from the internal platform and which has a sealing wall 23'” extending opposite the internal platform 21 ” ' on the side opposite the blade 20' '; a connecting wall 22”' connecting the internal platform 21’” to the sealing wall 23’” and having an upstream surface and a downstream surface;

[0088] Here, the means for limiting an injection of said recirculation flow radially from the inside into the upstream region 90 of the primary flow stream comprise a pressure balancing configuration, in which the connecting wall 22'” connects a downstream end of the internal platform 21”’ to a downstream end of the sealing wall 23'” so that the connecting 22”’, internal 21’” and sealing 23”’ walls delimit an internal C-section rectifier cavity 7’ opening towards the upstream of the rectifier vane 2’”.

[0089] As visible in [Fig.4], the internal platform 21'” also has an upstream end extending axially upstream of the blade 20”’.

[0090] In this fourth embodiment, and as for the third embodiment, the downstream rotor blading 4' also comprises a pressure balancing configuration in which the connecting wall 42' of the downstream rotor blading 4' connects a downstream end of the internal platform 41' of the downstream rotor blading 4' to the compressor rotor shaft 6 so that the compressor rotor shaft 6 and the connecting walls 42' of the downstream rotor blading 4' and internal platform 41' of the downstream rotor blading 4' delimit an internal cavity 8 of the downstream rotor blading to C-section opening upstream of the 4' downstream rotor blade.

[0091] In a similar manner to the internal cavity 7' of the rectifier blade, the internal platform 41' of the downstream rotor blade 4' here has an upstream end extending axially upstream of the blade 40' of the downstream rotor blade 4'.

[0092] The compressor further comprises an annular tooth 44' formed on the outer periphery of the compressor shaft 6, and which is axially substantially aligned with the upstream end of the internal platform 41' of the downstream rotor blade 4'.

[0093] Furthermore, as illustrated in [Fig.5], the upstream rotor blade 3' of this embodiment comprises an annular wall 35 formed from a downstream end of the internal platform 31' of the upstream rotor blade and extending radially between the compressor rotor shaft 6 and the internal platform 31' of the upstream rotor blade 3'.

[0094] Thus, in this fourth embodiment, the means for limiting an injection of the recirculation flow radially from the inside into said upstream region of the primary flow stream do not comprise an air sampling channel.

Claims

Claims

1. Stator vane (2, 2', 2”, 2”') for a turbomachine compressor (12), said stator vane comprising: an internal platform (21, 21', 21”, 21'”) intended to internally delimit a primary flow stream intended to supply a combustion chamber; at least one blade (20, 20', 20”, 20'”) extending radially outward from said internal platform (21, 21', 21”, 21”'); a root which extends radially inward from the inner platform and which has a sealing wall (23, 23', 23”, 23'”) extending opposite the inner platform (21, 21', 21”, 21'”) radially on the side opposite the blade (20, 20', 20”, 20”') and intended to form, with a compressor rotor shaft (6), a rotating seal intended to limit the flow of an air recirculation flow from a downstream region (91) of the primary flow stream defined downstream of the rectifier vane (2, 2', 2”, 2'”) to an upstream region (90) of the primary flow stream defined upstream of the rectifier vane (2, 2', 2”, 2'”); the foot comprising a connecting wall (22, 22', 22”, 22”') connecting said internal platform (21, 21', 21”, 21”') to said sealing wall (23, 23', 23”, 23”') and having an upstream surface and a downstream surface; characterized in that said rectifier vane (2, 2', 2”, 2'”) comprises means for limiting an injection of said recirculation flow radially from the inside into said upstream region (90) of the primary flow stream, said means comprising at least one of: an air sampling channel (24, 24', 24”), having an air inlet (240, 240', 240”) opening through at least one of a radially internal surface of the internal platform (21, 21', 21”) and said upstream and downstream surfaces of the connecting wall (22, 22'), and an air outlet (241, 241', 241”) opening through a region of the blade (20, 20', 20”) remote from the internal platform (21, 21', 21”); and a pressure balancing configuration, wherein said connecting wall (22”, 22'”) connects a downstream end of said internal platform (21”, 21'”) to a downstream end of said sealing wall (23”, 23'”) such that the connecting wall (22”, 22'”), the platform internal and the sealing wall (23”, 23”') delimit an internal cavity (7, 7') of the C-section rectifier opening upstream of said rectifier vane (2”, 2'”), said air outlet (241) opening onto an upstream face of said blade (20), close to a radially external edge of said blade (20).

2. A rectifier vane according to claim 1, characterized in that said air outlet (241', 241”) is provided on a radially external end of said blade (20', 20”) so as to be able to open into an air reinjection passage which extends into the compressor casing (12).

3. Straightening vane according to one of the preceding claims, characterized in that said internal platform (21”, 21'”) has an upstream end extending axially upstream of said blade (20”, 20'”).

4. Turbomachine compressor (12) comprising at least: a casing (5) which extends peripherally so as to delimit radially, externally, a flow vein of a primary flow intended to supply a combustion chamber; a compressor rotor shaft (6); a rectifier vane (2, 2', 2”, 2'”) according to one of claims 1 to 3; an upstream rotor blade (3, 3') arranged upstream of said rectifier blade (2, 2', 2”, 2'”), said rectifier blade (2, 2', 2”, 2”') and said upstream rotor blade (3, 3') delimiting an upstream region (90) of said primary flow stream, said upstream rotor blade (3, 3') comprising: an internal platform (31, 31') intended to radially delimit, internally, said primary flow stream intended to supply a combustion chamber; a blade (30, 30') extending radially outwards from said internal platform (31, 31');a connecting wall (32, 32') connecting said internal platform (31, 31') to said compressor rotor shaft (6) and having an upstream surface and a downstream surface; a downstream rotor blade (4, 4') arranged downstream of said rectifier blade (2, 2', 2”, 2”'), said rectifier blade (2, 2', 2”, 2'”) and said downstream rotor blade (4, 4') delimiting a downstream region (91), said downstream rotor blade (4, 4') comprising:; an internal platform (41, 41') intended to radially delimit, internally, said primary flow stream intended to supply a combustion chamber; a blade (40, 40') extending radially outwards from said internal platform (41, 41'); a connecting wall (42, 42') connecting said internal platform (41, 41') to said compressor rotor shaft (6) and having an upstream surface and a downstream surface.

5. Compressor according to the preceding claim, characterized in that the downstream rotor blade (4') further comprises a pressure balancing configuration in which said connecting wall (42') of the downstream rotor blade (4') connects a downstream end of said internal platform (41') of the downstream rotor blade (4') to said compressor rotor shaft (6) so that said compressor rotor shaft (6) and said connecting wall (42') of the downstream rotor blade (4') and internal platform (41') of the downstream rotor blade (4') delimit an internal cavity (8) of the downstream rotor blade with a C-shaped section opening towards the upstream of said downstream rotor blade (4').

6. Compressor according to the preceding claim, characterized in that said internal platform (41') of the downstream rotor blade (4') has an upstream end extending axially upstream of said blade (40') of the downstream rotor blade (4').

7. Compressor according to the preceding claim, characterized in that it comprises an annular tooth (44') provided on the external periphery of the rotor shaft of the compressor (6), axially substantially aligned with said upstream end of the internal platform (41') of the downstream rotor blade (4').

8. Compressor according to one of claims 4 to 7, characterized in that the upstream rotor blade (3') comprises an annular wall (35) formed from a downstream end of said internal platform (31') of the upstream rotor blade (3') and extending radially between said compressor rotor shaft (6) and said internal platform (31') of the upstream rotor blade (3').

9. Turbomachine for aircraft, in particular a turbojet, comprising a compressor according to one of claims 4 to 8.

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