FR3030627A1 - SERVITUDE PASSAGE SYSTEM FOR TURBOMACHINE - Google Patents

Abstract

System (40) for the passage of servitudes (68) for a turbomachine, comprising a body having two coaxial annular shrouds, radially inner (42) and outer (44) respectively, connected together by substantially radial and tubular arms (46 ") which comprise internal accommodation (62) passage easements, characterized in that at least one of the arms is formed integrally with at least a portion (64) of a fluid conduit (68), such a fluid drainage conduit, which is configured such that said fluid is isolated from the internal housing for passage of servitudes of said arm.

Description

The present invention relates in particular to a system for the passage of servitudes for a turbomachine, in particular an aircraft. STATE OF THE ART A turbomachine with a double flow comprises a flow vein of a primary flow or hot flow and a flow vein of a secondary flow or cold flow.

A turbomachine is generally equipped with at least one system for passing servitudes such as air ducts, oil ducts, electrical cables, etc., so that they can pass through a vein such as the vein of flow of the secondary flow, without disturbing this flow. The easements make it possible to connect a first equipment located radially outside the vein to a second equipment located radially inside the vein (the expression "radially" appreciating with respect to the longitudinal axis of the turbomachine , which is the axis of rotation of its rotors). A system of passage of servitudes (commonly called kit engine) generally comprises an annular body having two annular ferrules coaxial, respectively radially inner and outer, and connected together by substantially radial and tubular arms which comprise internal housings passage easements ( see for example EP-A1-1 741 879 and WO-A2-2010 / 007220).

This system can be mounted directly downstream of an intermediate casing of the turbomachine. The intermediate casing comprises an inner hub surrounded by a coaxial annular shroud and connected thereto by radial vanes which have an aerodynamic profile. The arms of the easement passage system extend downstream and in the extension of some blades of the intermediate casing so as not to disturb the flow of the secondary air flow flowing between the vanes of the intermediate casing. The documents FR-A1-2 875 855 and FR-A1-2 899 272 describe servo arms for turbomachines.

The purpose of the system's ferrules is to reconstitute the aerodynamic flow vein of the airflow. The inner ferrule extends around the engine body of the turbomachine and comprises radial openings connected to discharge ducts (also called VBV ducts, VBV being the acronym for the English term Variable Bleed Valve).

It has been found that there is a fluid retention zone on the radially internal face of the inner ferrule, in the lower part of this ferrule, that is to say at about 6 hours (or 6 hours) by analogy with the dial. of a clock. This zone is located between two discharge ducts and at the right of an arm 6h of the system.

In case of leakage of conduits (oil, fuel, etc.) at the engine body, fluids can flow to this area and accumulate there, which represents a significant risk of occurrence of an engine fire because of the flammable nature of these fluids. Certain standards and certain aeronautical programs require very small volumes per retention zone to limit or even prevent the risk of engine fire. The present invention makes it possible to remedy this problem simply, efficiently and economically. DESCRIPTION OF THE INVENTION The invention proposes a system for the passage of servitudes for a turbomachine, comprising a body having two coaxial annular shrouds, radially inner and outer respectively, connected together by substantially radial and tubular arms which comprise internal passage housings. characterized in that at least one of the arms is formed in one piece with at least a portion of a fluid conduit, such as a fluid drainage conduit, which is configured so that said fluid is isolated from the internal housing for the passage of servitudes of said arm. The fluid drainage duct is thus integrated into an arm of the system, which makes it possible to solve several problems. First, the inner housing of the arm for the passage of easements can already be encumbered by fluid conduits and may not be able to accommodate another conduit. In addition, the drained fluids (especially oil and fuel) are flammable and it is therefore important that their drainage is carried out in a sealed manner because the arm extends between the engine compartment and the nacelle compartment, which form two separate fire compartments. The arm must prevent any spread of fire from one compartment to another. The integration of the fluid conduit to the arm facilitates the isolation of these compartments. The housing of the arm can be used as a passage for a high temperature and high pressure air duct which is taken from a high pressure compressor of the engine, for example for defrosting parts of the aircraft equipped with the turbomachine such as the leading edges of the wings or the lips of the air intakes of the nacelles. The integration of the fluid drainage conduit in the arm better isolates it from this hot air duct and thus limit the risk of ignition of fluids circulating in the integrated duct. The invention also makes it possible to impact the minimum number of parts in the environment in question in order to limit the complexity of the solution. It also makes it possible to overcome the risk of breakage of the drainage duct by vibratory shocks during operation, and makes it possible to simplify assembly without having to mount the duct in the arm. The system according to the invention may comprise one or more of the following characteristics, taken separately from each other or in combination with each other: said arm is an arm six or twelve hours by analogy with the dial of a clock; at least a first substantially radial portion of said duct is formed in one piece with the arm; said first part extends along and in the vicinity of a trailing or leading edge of the arm; said first part is defined in an oversize of material of the arm; a second portion of said duct extends along a longitudinal edge of the arm and comprises a first end connected to a radially outer end of said first portion; a second end of said second portion is bent and / or connected to a flange configured to be connected to a fluid discharge circuit; and a radially inner end of said first part is connected to a drainage orifice of a bottom wall of said arm.

The present invention further relates to a method of producing a system as described above, characterized in that said at least a portion of the fluid conduit is obtained by casting with said arm. The invention also relates to a turbomachine, characterized in that it comprises a system as described above.

DESCRIPTION OF THE FIGURES The invention will be better understood and other details, characteristics and advantages of the invention will emerge more clearly on reading the following description given by way of nonlimiting example and with reference to the appended drawings in which: FIG. 1 is a diagrammatic view in axial section of a turbomachine with a double flow; FIG. 2 is a very diagrammatic view of a servitude passage system for a turbomachine; FIG. 3 is a diagrammatic view of a FIG. 4 is a diagrammatic perspective view of a part of a system of passage of easements according to the invention, and shows a radially inner end of an arm of this system; FIG. 5 is another partial perspective view of the system of FIG. 4 and shows a radially external end of the arm of this system; FIG. 6 is a schematic perspective view of the arm of FIGS. 4 and 5; FIG. 7 is an enlarged view of a portion of FIG. 6, and FIG. 8 is a sectional view along the line AA of FIG. 7. DETAILED DESCRIPTION As illustrated in FIG. schematic in axial section of a turbomachine with double flow 10, such a turbomachine generally comprises, from upstream to downstream in the direction of flow of the gases, a low pressure compressor 12, a high pressure compressor 14, a combustion chamber 16, a high-pressure turbine 18 and a low-pressure turbine 20, which define a flow vein of a primary flow of gas 22. The rotor of the high-pressure turbine 18 is integral with the rotor of the high-pressure compressor 14 so as to form a high pressure body, while the rotor of the low pressure turbine 20 is secured to the rotor of the low pressure compressor 12 so as to form a low pressure body. The rotor of each turbine rotates the rotor of the associated compressor about an axis 24 under the effect of the thrust of the gases from the combustion chamber 16. An intermediate casing 26 is usually interposed between the low pressure compressors 12 and 14. In the case of turbofan engines, which comprise a fan 28 streamlined by a nacelle 30 for generating a secondary stream 32, the intermediate casing 26 generally comprises vanes 34 passing through the flow channel of this stream secondary 32.

Referring now to FIG. 2, a very schematic view of a system 40 for the passage of servitudes also called the "engine kit" of a turbomachine, this system 40 typically comprising two coaxial annular shrouds, internal 42 and outer 44 respectively, between radial arms 46, 46 ', 46 "extend in a turbojet engine of the type shown in FIG. 1, this system 40 is mounted downstream of the intermediate casing 26 so that its arms 46, 46 ', 46' extend downstream and in line with some of the vanes of the intermediate casing. The ferrules 42, 44 delimit between them, downstream of the casing 26, the annular vein of passage of the secondary flow 32. In the example shown in Figure 2, the system 40 comprises four arms 46, 46 ', 46 "which are respectively located at 3h, 6h, 9h and 12h, by analogy with the dial of a clock.The arms 46, 46 ', 46 "have profiles and transverse dimensions which depend in particular on their function and aerodynamic constraints related in particular to performance expected from the engine. The system 40 here comprises an arm 46 to 12h relatively thick transversely, that is to say having a relatively large master torque, and three arms 46 ', 46 "to 3h, 6h and 9h which are relatively thin transversely, it that is to say they have a relatively low torque master The arms 46, 46 ', 46 "define internal housings for the passage of easements. Easements can be ducts, pipes, electrical harnesses, etc. They extend between the inner and outer shells 42 and 44, substantially radially with respect to the longitudinal axis of the system. Each arm 46, 46 ', 46 "(Figure 3) has a dihedral shape and comprises two side walls 48 whose downstream radial edges are interconnected to form a trailing edge 50 of the arm.

Reference numeral 52 in FIG. 2 denotes a fluid retention zone. This is an area located on the radially inner face of the shell 42, at 6 o'clock, at which fluids, such as oil and fuel, can flow and accumulate, these fluids from the engine which extends inside the shell 42. The invention proposes a simple and effective solution for draining these fluids from the zone 52 to the outside of the shell 44, via the arm 46 ", which extends to 6h and therefore substantially to the right of the zone 52. For this, the invention proposes that the arm 6h 46" is formed in one piece with at least a portion of a drainage duct fluid, which is configured such that said fluid is isolated from the servitude passage housing of said arm. Alternatively, the invention could be applied to another position. Thus, if we wanted to achieve drainage of the outer part of the turbomachine, to the inner part, the invention would remain applicable and the arm in question would then be positioned in the upper half of the dial, or rather to 12h than to 6h. Figures 4 to 8 illustrate an exemplary embodiment of the present invention in which the elements already described in the foregoing are designated by the same references. FIG. 4 shows the radially inner end of the arm 6h 46 "as well as the radially inner face 53 of the shell 42 of the system 40 according to the invention: it can be seen that the arm 46" has at its radially inner end a bottom wall 54 which is fixed, for example by means of the screw-nut type, on the shell 42 and which closes the inner housing of the arm 46 ". This bottom wall 54 can participate in the insulation of the engine compartment located at the inside the ferrule 42, the nacelle compartment located outside the ferrule 44, in particular to prevent the propagation of a fire from one compartment to another The aforementioned zone 52 for the potential retention of fluids extends here on the radially inner face of the bottom wall 54, between two discharge ducts 57 mounted on the radially inner face 53 of the shell 42, on either side of the bottom wall 54. In the example shown, the inner housing of arm 46 "is used for serving studies comprising a duct 56 of hot air at high pressure, which is taken from the high pressure compressor, and which can be used to de-ice parts of the aircraft equipped with the turbomachine, and oil ducts 58, here in number of two. The servitudes 56, 58 are rather located in the vicinity of the upstream end of the arm 46. Figure 5 shows the radially outer end of the arm 6h 46 "and the radially outer face 60 of the shell 44 of the system 40. notes that this end of the arm is open and that the inner housing 62 of the arm 46 "is very crowded by the easements 56, 58. The pipe 56 occupies for example substantially all the space in the vicinity of the upstream end of the arm 46 ".

In the example shown, the arm 46 "is formed in one piece with two parts 64, 66 of a conduit 62 for fluid drainage, namely a first portion 64 substantially radial (Figure 6) and a second portion 66 substantially longitudinal (Figures 7 and 8) The portions 64, 66 of the duct 68 are visible by transparency in Figures 6 and 7.

The first portion 64 of the duct 68 extends along and in the vicinity of the trailing edge 50 of the arm 46 ", as can be seen in FIG. 6. It is formed in an extra material thickness of the arm 46" and extends over substantially the entire radial dimension of the arm. The radially inner end of this portion 64 of the duct 68 opens on the inner face of the bottom wall 54 to form a drainage orifice 70, which here has a generally trapezoidal or triangular shape imposed by the shape of the end portion downstream of the arm forming the trailing edge 50. The orifice 70 is located in the vicinity of the downstream end of the bottom wall 54 and may be located at the bottom of a bath 72 of this bottom wall, whose function would be collecting and conveying the fluids to drain to the orifice 70. The fluids are then intended to flow by gravity inside the portion 64 of the conduit 68, as shown in FIG. arrows. The second portion 66 of the duct 68 extends along a radially outer longitudinal edge of a side wall 48 of the arm 46 ", as can be seen in FIGS. 7 and 8. It is formed in an extra thickness of the arm material 46 "and extends over a major part of the longitudinal dimension of the arm, extending along the aforementioned axis 24. The radially outer end of the portion 64 of the conduit 68 is connected to a downstream end of its portion 66 by a first bend 74. The upstream end of the portion 66 of the conduit 68 is connected by a second bend 76 to a portion of pipe 78, which is itself connected to a flange 80 for connection to a drainage circuit (not shown). The pipe portion 78 and the flange 80, better visible in FIG. 5, extend radially outside the arm 46 "and the shell 44, so as to facilitate the connection to the drainage circuit. allows the drained fluids to be guided in a desired direction The flange 80 here comprises a fastener tab 82 by screw-nut means to a circuit element and further comprises means 84 (such as a diameter ) to center this element so that the fluid outlet of the flange is positioned correctly with respect to a fluid inlet of the circuit Fluid flowing along the portion 64 of the conduit 68 then flow in the portion 66 to the flange 80 and the drainage circuit, as shown in Figure 6 by the arrows.

As seen in the drawings, the portions 64, 66 of the duct 68, as well as the elbows 74, 76, are formed in one piece with the arm 46. The arm 46 "is preferably made of castings. In this case, the inner housing 62 of the arm 46 "and the internal passages of the parts 64, 66 and elbows 74, 76 of the conduit 68 may be defined by fusible cores, as is well known to those skilled in the art.

Claims (10)

REVENDICATIONS1. System (40) for the passage of servitudes (56, 58, 68) for a turbomachine, comprising a body having two coaxial annular shrouds, radially inner (42) and outer (44), respectively, connected together by arms (46, 46 ' , 46 ") which are substantially radial and tubular and which comprise internal servitude passageways (62), characterized in that at least one (46") of the arms is formed in one piece with at least one part ( 64, 66) of a fluid conduit (68), such as a fluid drainage conduit, which is configured such that said fluid is isolated from the internal servicing housing (62) of said arm. 2. System (40) according to claim 1, wherein said arm (46 ") is an arm six or twelve hours by analogy with the dial of a clock. The system (40) of claim 1 or 2, wherein at least a first substantially radial portion (64) of said conduit (68) is integrally formed with the arm (46 "). The system (40) of claim 3, wherein said first portion (64) extends along and adjacent a trailing edge (50) or leading edge of the arm (46 "). 5. System (40) according to claim 3 or 4, wherein said first portion (64) is defined in a material thickness of the arm (46 "). The system (40) according to one of claims 3 to 5, wherein a second portion (66) of said duct (68) extends along a longitudinal edge of the arm (46 ") and comprises a first end connected to a radially outer end of said first portion (64). The system (40) of claim 6, wherein a second end of said second portion (66) is bent and / or connected to a flange (80) configured to be connected to a fluid discharge circuit. 8. System (40) according to one of claims 3 to 7, wherein a radially inner end of said first portion (64) is connected to a drain hole (70) of a bottom wall (54) of said arm (46 "). 9. A method of producing a system (40) according to one of the preceding claims, characterized in that said at least one portion (64, 68) of the fluid duct (68) is obtained by casting with said arm (46). "). 10. Turbomachine, characterized in that it comprises a system (40) according to one of claims 1 to 8.