Turbine engine for an aircraft comprising a duct for discharging engine fluids

Abstract

The invention relates to a turbine engine for an aircraft, said turbine engine comprising: a fan that generates an air flow, referred to as the secondary flow; a gas generator, through which a gas flow passes, referred to as the primary flow; a reinforcing structure (40) arranged around the gas generator and at least partially defining a fire zone (G) containing the gas generator, said reinforcing structure (40) forming a fire barrier and comprising, in a lower portion thereof, a discharge duct (46) forming a passage that connects the fire zone (G) with the outside of the turbine engine so as to allow fluids to be discharged by gravity, the discharge duct (46) being configured to form a fire barrier and to contain an engine fluid discharge pipe (48).

Description

Aircraft turbomachine incorporating an engine fluid drain duct Technical Field

[0001] The present invention relates to the field of aeronautics, and more particularly to a propulsion assembly comprising a turbomachine, in particular a triple-flow turbomachine comprising an unshod fan or a double-flow turbomachine comprising a shod fan. State of the art

[0002] Aircraft are known to be powered by at least one propulsion system incorporating a turbomachine, such as a turbofan engine. Each propulsion system is attached to the aircraft by a pylon, usually located under or on a wing, or at the level of the aircraft's fuselage. A turbofan engine primarily consists of a gas generator and a fan.

[0003] The fan can be enclosed, in which case the turbojet engine is housed in a nacelle. The fan can also be unenclosed, as is the case with turbojet engines known as "open fan" or "unducted single fan".

[0004] The gas generator includes, from upstream to downstream with respect to the direction of gas flow, a rectifier, a low-pressure compressor and a high-pressure compressor.

[0005] During operation, an airflow is accelerated by the fan, then splits into a primary flow and a secondary flow. The primary flow enters a primary gas circulation channel passing through the turbojet's gas generator.

[0006] In the case of a shrouded fan, the secondary flow is directed into a secondary stream surrounding the gas generator. This secondary stream is bounded radially inward, partly by an internal nacelle structure that encloses the gas generator, and radially outward, partly by an external nacelle structure that surrounds the turbofan engine. A portion of the secondary stream is further bounded radially outward by a fan casing surrounding the fan and by an intermediate casing located downstream of the fan casing. In the case of an unshrouded fan, the secondary flow is also generated by the fan but is open and flows outside the turbomachine, around the gas generator.

[0007] In the case of an unfaired fan, it can be advantageous to provide a third flow, called tertiary flow. This flow circulates in an annular channel surrounding the gas generator, the annular channel itself being enclosed by a portion of the engine's fairing, so that the tertiary flow circulates between the primary and secondary flows. An engine with such an architecture generally includes a reinforcing structure surrounding the gas generator along at least part of its length, this structure being itself enclosed by the structure forming the annular channel through which the tertiary flow circulates.

[0008] The reinforcement structure performs several functions, including structural support and fire protection. However, this reinforcement structure is typically interrupted at its lower end, at the 6 o'clock position, to allow for the passage of components such as a drain mast. This allows for the drainage and evacuation of various fluids used in engine operation, such as lubricant, coolant, etc., from the turbomachine. This configuration necessitates the creation of a fire containment zone, known as a "fire zone," which encompasses the reinforcement structure. This requires, in particular, the installation of fire-resistant seals, called fire gaskets, around this zone. Such a configuration increases the risk of a fire starting and / or spreading outside the engine compartment.

[0009] The objective of the present invention is to provide a turbomachine that reduces the risk of a fire starting and spreading outside the engine compartment. Description of the invention

[0010] To this end, the invention relates to an aircraft turbomachine comprising a fan generating an airflow called secondary flow, the turbomachine comprising a gas generator through which a gas flow called primary flow passes, the turbomachine comprising a reinforcement structure arranged around the gas generator and delimiting at least in part a fire zone containing the gas generator, the reinforcement structure forming a fire barrier, the reinforcement structure comprising in its lower part an evacuation duct forming a passage connecting the fire zone and the outside of the turbomachine so as to allow the evacuation of fluids by gravity, the evacuation duct being configured to form a fire barrier and to contain an engine fluid evacuation mast.

[0011] Thus, by incorporating an exhaust duct directly connected to the reinforcement structure, so that the reinforcement structure forms a fire barrier, it is possible to define a fire zone that does not extend beyond the reinforcement structure. This improves the turbomachine's fire resistance. Indeed, the various fluids used for engine operation that could flow into the fire zone can be easily and safely evacuated from the turbomachine. Furthermore, it is no longer necessary to provide fireproof seals on the exterior of the reinforcement structure, which simplifies turbomachine assembly and reduces manufacturing costs.

[0012] The turbomachine according to the invention may include one or more of the following optional features, considered alone or in all possible combinations.

[0013] According to one characteristic, the exhaust duct passes through an external structure of the turbomachine, the external structure forming part of a fairing of the turbomachine.

[0014] According to one characteristic, the exhaust duct is fixed relative to the reinforcement structure.

[0015] According to one characteristic, the turbomachine includes a propeller forming an unfaired fan.

[0016] According to one characteristic, the external structure of the turbomachine defines an annular vein for the circulation of a tertiary flow.

[0017] According to one characteristic, the external structure is formed of two half-parts articulated around an axis parallel to a longitudinal axis of the turbomachine, the exhaust duct being located at the junction of the two half-parts.

[0018] According to one characteristic, each half-part is mobile in rotation around an axis parallel to the longitudinal axis of the turbomachine, between an operating position and an open position, the discharge conduit being disposed at the junction of the two half-parts when they are in the operating position, the discharge conduit remaining fixed when the half-parts pass from the operating position to the open position.

[0019] According to one characteristic, the fluid discharge mast is positioned within the discharge duct so as to maintain a free space between the inner wall of the discharge duct and the discharge mast.

[0020] Depending on a characteristic, the exhaust duct is attached to the reinforcement structure, for example by welding, bolting, screwing or riveting.

[0021] According to one characteristic, the exhaust duct has in its upper part a portion for connection with the reinforcement structure, the portion for connection having a flared shape.

[0022] According to one characteristic, the reinforcement structure is formed by a set of adjacent elements distributed around a longitudinal axis of the turbomachine, the adjacent elements being connected to each other, for example by welding, bolting, screwing or riveting.

[0023] According to one characteristic, the exhaust duct came from the material with one of the adjacent elements forming the reinforcement structure.

[0024] According to one characteristic, the exhaust duct and the reinforcement structure are made of a metal alloy, for example a titanium-based alloy.

[0025] The invention also relates to an aircraft comprising at least one propulsion assembly including a turbomachine conforming to that defined above. Brief description of the drawings

[0026] Figure 1 is a schematic half-view in cross-section of a turbomachine according to the invention.

[0027] Figure 2 is a partial cross-sectional view of the turbomachine of Figure 1, according to a first embodiment.

[0028] Figure 3 is a partial cross-sectional view in plane AA of the turbomachine of Figure 2.

[0029] Figure 4 is a partial cross-sectional view of the turbomachine of Figure 1, according to a second embodiment.

[0030] Figure 5 is a partial cross-sectional view in plane BB of the turbomachine of Figure 4.

[0031] Figure 6 is a view analogous to Figure 3, with the halves in an open position.

[0032] Detailed description

[0033] Figure 1 is a schematic cross-sectional view of a turbomachine 1 according to the invention, intended for mounting on an aircraft such as an airplane. The turbomachine 1 shown extends along a longitudinal axis X and comprises a gas generator and a propulsion module equipped with an unducted propeller. Such a turbomachine is of the type known as an "open rotor," "unducted fan," or "open fan." Within this category of turbomachine, there are those with two unducted, counter-rotating propellers (known as UDF for "Unducted Dual Fan") and those with a single unducted propeller and an unducted stator comprising several stator blades (known as USF for "Unducted Single Fan"). The invention is also applicable to other types of turbomachines, such as turbojets, and in particular turbofans with a ducted fan.

[0034] In this description, and generally, the terms "upstream", "downstream", "axial" and "axially" are defined with respect to the flow of gases in the turbomachine and with respect to the longitudinal axis X of the turbomachine 1. Similarly, the terms "radial", "radially", "internal" and "external" are defined with respect to a radial axis perpendicular to the longitudinal axis X and with respect to the distance from the longitudinal axis X.

[0035] In Figure 1, the turbomachine 1 comprises a propulsion module 10 and a gas generator 20. The gas generator 20 typically comprises, from upstream to downstream, a low-pressure compressor 22 (or "booster"), a high-pressure compressor 24, a combustion chamber 26, a high-pressure turbine 28 and a low-pressure turbine 30.

[0036] The propulsion module 10 includes a propeller 12 which is arranged upstream of the gas generator 20. The propeller 12 comprises a plurality of movable blades 12a about the longitudinal axis X and extending radially from an internal casing 14 forming the hub of the propeller 12. The movable blades 12a can have variable pitch, that is to say movable about a pitch axis perpendicular to the longitudinal axis X.

[0037] In the example, a stator 16 is arranged downstream of the propeller 12. The stator 16 comprises a plurality of stator vanes 16a (or fixed vanes) known by the English acronym "OGV" for Outlet Guide Vane. In this description, the term "stator vane" or "fixed vane" refers to a vane that is not driven in rotation about the longitudinal axis X of the turbomachine. The stator vanes 16a are distributed around the longitudinal axis X and are arranged downstream of the moving blades 12a of the propeller 12, so as to straighten the airflow generated by the latter.

[0038] The stator blades 16a of the rectifier 16 can have variable or fixed pitch. The airflow F passing through the propeller 12 is split into a first flow Fl and a second flow, or secondary flow F2, by a separating nozzle 18. The separating nozzle 18 forms the upstream end of an external structure 32 centered on the longitudinal axis X and surrounding the gas generator 20.

[0039] The first flow Fl is divided into a primary flow Fil, which circulates in a primary channel 34, and a tertiary flow F3, which circulates in an annular tertiary channel 36 surrounding the primary channel 34. The secondary flow F2 circulates radially outside the tertiary channel 36. In particular, the secondary flow F2 circulates radially outside the external structure 32 and sweeps the unfaired rectifier 16. The tertiary flow F3 is a cold air flow and circulates in the tertiary channel 36 until it is ejected downstream of the turbomachine 1. The primary flow Fil circulates through the gas generator 20, where it undergoes the thermodynamic cycle before being ejected downstream of the turbomachine 1.

[0040] As can be seen in Figures 2 and 3, which illustrate a first variant of the turbomachine of Figure 1, a reinforcing structure 40 is arranged around the gas generator 20, along at least part of its length. The reinforcing structure 40 is at least partially enclosed by the external structure 32. The reinforcing structure 40 delimits a fire zone G within which the gas generator 20 is located. In the example, the reinforcing structure 40 is formed by a set of adjacent elements 42, 44 distributed around the longitudinal axis X, and connected to each other to form a fire barrier. The adjacent elements 42, 44 forming the reinforcing structure are connected in pairs, for example, by welding, bolting, screwing, or riveting. One of the elements 42, 44 is a lower element 44, arranged at the bottom, in the so-called "six o'clock" position. The lower element 44 has an opening 440 and is connected to an exhaust duct 46.The drain duct 46 connects, via opening 440, the fire zone G, containing the gas generator 20, to the exterior of the turbomachine 1, thus allowing the gravity drainage of various fluids that may be present within the fire zone (lubricant, fuel, coolant, etc.). Furthermore, the drain duct 46 is configured to house a drain mast 48. The drain mast 48, in a known manner, ensures the targeted recovery of the various fluids used in the engine's operation (fuel, lubricant, coolant) that may leak from their respective circuits, for example, in the event of a leak. To this end, the drain mast 48 is connected to several conduits 48a, each conduit 48a being dedicated to a specific fluid and / or a specific sampling zone.In the example, the evacuation duct 46 is configured to contain the evacuation mast 48, and so as to maintain a free space E between the evacuation mast 48 and the internal wall 46a of the evacuation duct 46. In particular, no seal (waterproof or fireproof) is disposed between the internal wall 46a of the evacuation duct 46 and the evacuation mast 48.

[0041] As mentioned above, the exhaust duct 46 connects the fire zone G, which contains the gas generator 20, to the exterior of the turbomachine 1. As can be seen in Figure 3, the exhaust duct 46 therefore passes through the external structure 32. In the case of an unshod turbomachine that does not generate tertiary flow, the external structure can be formed by one or more cowlings. In the example shown in the figures, the turbomachine 1 generates a tertiary flow F3, and the external structure 32 defines the tertiary channel 36 through which this flow circulates. In the example shown in the figures, the external structure 32 comprises two half-parts 32a forming a "D-duct" architecture. More precisely, each half-part 32a of the external structure 32 has an inner part 320 and an outer part 322.For each half-part 32a, the outer part 322 is arranged around the corresponding inner part 320. The inner part 320 and the outer part 322 of each half-part 32a are spaced so as to delimit at least a portion of the annular vein 36. The inner part 320 and the outer part 322 of each half-part 32a are connected, at the so-called "six o'clock" position, by a connecting wall 324. The connecting walls 324 form a lower bifurcation within the annular vein 36. The inner part 320 of each half-part 32a is arranged around the reinforcing structure 40. Thus, each half-part 32a covers a portion of the reinforcing structure 40.The two halves 32a are hinged around a rotation axis parallel to the longitudinal axis X and located near the so-called "twelve o'clock" position, allowing the two halves 32a to be opened to access the gas generator 20, particularly during maintenance operations. Thus, each half 32a is rotatable between an operating position, shown in Figure 3, and an open position, shown in Figure 6 (the halves 32a are not visible in the partial view of Figure 6). In the configuration shown in the figures, the drain duct 46 is located between the two halves 32a of the external structure 32, at their junction. In the example, the drain duct 46 is located between the connecting walls 324 when the two halves 32a are in the operating position. The exhaust duct 46 is fixed relative to the reinforcement structure 40.Thus, the position of the discharge duct 46 remains unchanged when the half-sections 32a are moved from their operating position to their open position (and vice versa), as shown in Figure 6. Figure 6 is a view analogous to Figure 3, with the half-sections 32a in their open, or maintenance, position. In this position, the half-sections 32a are separated from each other to allow access to certain parts of the turbomachine, and in particular to certain parts of the gas generator 20. As mentioned above, moving one or both half-sections 32a from the operating position (shown in particular in Figure 3) to the open position does not change the position of the discharge duct 46, as it remains fixed relative to the reinforcing structure 40.As can be seen in Figure 6, when the halves 32a of the external structure 32 are in the open position, the evacuation conduit 46 is directly accessible, for example for maintenance operations.

[0042] In the example of figures 2 and 3, the evacuation conduit 46 is attached to the lower element 44 of the reinforcement structure 40, for example by welding, bolting, screwing or riveting.

[0043] Figures 4 and 5 represent a second variant of the turbomachine 1, in which the exhaust duct 46 is made of the same material as the lower element 44 of the reinforcing structure 40. The exhaust duct 46 and the lower element 44 thus form a single-piece structure, which can for example be made by molding.

[0044] In the example in the figures, the evacuation conduit 46 is arranged, along the longitudinal axis X, between two locking elements 32b allowing the half-parts 32a of the external structure 32 to be locked together.

[0045] As shown in the figures, the exhaust duct 46 may have a flared section at its upper end connecting to the reinforcing structure. Advantageously, this flared section may only be in a plane parallel to the longitudinal axis X.

[0046] The reinforcement structure 40 and the evacuation conduit 46 are made of a metallic alloy which can fulfill the functions of force transmission and fire barrier, for example a titanium-based alloy.

[0047] In an alternative variant not shown, the reinforcement structure 40 is a single piece. In this variant, the exhaust duct 46 can be attached to the reinforcement structure 40, or can be formed from the same material as the reinforcement structure 40.

Claims

Demands

1. Turbomachine (1) for aircraft comprising a fan generating an airflow called secondary flow (F2), the turbomachine (1) comprising a gas generator (20) through which a gas flow called primary flow (Fil) passes, the turbomachine (1) comprising a reinforcement structure (40) arranged around the gas generator (20) and delimiting at least in part a fire zone (G) containing the gas generator (20), the reinforcement structure (40) forming a fire barrier, the reinforcement structure (40) comprising in its lower part an exhaust duct (46) forming a passage connecting the fire zone (G) and the exterior of the turbomachine (1) so as to allow the evacuation of fluids by gravity, the exhaust duct (46) being configured to form a fire barrier and to contain an engine fluid evacuation mast (48).

2. Turbomachine (1) according to the preceding claim, wherein the exhaust duct (46) passes through an external structure (32) of the turbomachine (1), the external structure (32) forming part of a fairing of the turbomachine (1).

3. Turbomachine according to any one of the preceding claims, wherein the exhaust duct (40) is fixed relative to the reinforcement structure (40).

4. Turbomachine (1) according to any one of the preceding claims, comprising a propeller (12) forming an unfaired fan.

5. Turbomachine (1) according to any one of claims 2 and 3, in combination with claim 4, wherein the external structure (32) defines an annular vein (36) for the circulation of a tertiary flow (F3).

6. Turbomachine (1) according to any one of claims 2 to 5, wherein the external structure (32) is formed of two half-parts (32a) articulated about an axis parallel to a longitudinal axis (X) of the turbomachine (1), the exhaust duct (46) being disposed at the junction of the two half-parts (32a).

7. Turbomachine (1) according to the preceding claim, wherein each half-part (32a) is rotationally movable about an axis parallel to the longitudinal axis (X) of the turbomachine (1), between an operating position and an open position, the discharge conduit (46) being disposed at the junction of the two half-parts (32a) when they are in the operating position, the discharge conduit (46) remaining fixed during the passage of the half-parts (32a) from the operating position to the open position.

8. Turbomachine (1) according to any one of the preceding claims, wherein the fluid discharge mast (48) is arranged within the discharge duct (46) so as to maintain a free space (E) between the inner wall (46a) of the discharge duct (46) and the discharge mast (48).

9. Turbomachine (1) according to any one of the preceding claims, wherein the discharge conduit (46) is attached to the reinforcement structure (40), for example by welding, bolting, screwing or riveting.

10. Turbomachine (1) according to any one of the preceding claims, wherein the reinforcement structure (40) is formed by a set of adjacent elements (42, 44) distributed around a longitudinal axis (X) of the turbomachine (1), the adjacent elements (42, 44) being connected to each other, for example by welding, bolting, screwing or riveting.

11. Turbomachine (1) according to the preceding claim, wherein the discharge conduit (46) is made of material with one of the adjacent elements (44) forming the reinforcement structure (40).

12. Turbomachine (1) according to any one of the preceding claims, wherein the discharge conduit (46) and the reinforcement structure (40) are made of a metallic alloy, for example a titanium-based alloy.

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