TEST BENCH FOR AN AIRCRAFT TURBOMACHINE

Abstract

The invention relates to a test bench for an aircraft turbomachine, comprising an aircraft turbomachine module (1) and at least one intrusive meter (21), the turbomachine comprising an annular casing (14, 16) in which a gas flow is intended to flow, the intrusive meter (21) comprising a body (22) of elongated shape along an axis (X2) and being mounted inside the casing (14, 16), the body (22) comprising a first longitudinal end (31) for connection to the casing (14, 16) and a second free longitudinal end (32) opposite the first longitudinal end (31). According to the invention, the first end (31) of the body (22) is connected to the housing (14, 16) such that the body (22) is free to rotate about said axis (X2), thus allowing the body (22) to automatically adopt a position about this axis (X2) according to the orientation of said gas flow. Figure for the abstract: Figure 3

Description

Title of the invention: TEST BENCH FOR AN AIRCRAFT TURBOMACHINE Technical field of the invention

[0001] The present invention relates to a test bench for an aircraft turbomachine, comprising an aircraft turbomachine module and at least one intrusive measuring device. Technical background

[0002] Figure 1 schematically represents a known turbomachine 10 of the twin-spool, twin-flow type to which the invention applies in particular. Of course, the invention is not limited to this particular type of turbojet and applies to other turbojet architectures.

[0003] The turbomachine 10 comprises, from upstream to downstream in the direction of the gas flow, a blower 11, one or more stages of compressors 12, a combustion chamber 13, one or more stages of turbines 15 and a gas exhaust nozzle.

[0004] The turbomachine 10 also includes an annular fan casing 14 and an intermediate annular casing 16, which, as is known per se, has a structural function because the forces are transmitted through it. In particular, the means for attaching the turbomachine 10 to the aircraft structure in the forward section are integral with the intermediate casing 16. The intermediate casing 16 consists, in particular, of a hub 17 and an outer annular ferrule 18 arranged coaxially around the hub with respect to the axis XI of the turbomachine 10.

[0005] The turbomachine 10 further comprises two coaxial gas flow channels, namely a primary flow channel 19 (or hot flow), and a secondary flow channel 20 (or cold flow) delimited at least in part by the fan casing 14 and / or the intermediate casing 16.

[0006] In the context of tests on a turbomachine 10, it is sometimes necessary to carry out measurements of the aerodynamic quantities, in particular of pressure and temperature, of the gas flow flowing in the flow veins 19, 20.

[0007] For this purpose, test benches are used comprising a turbomachine module 1 including all or part of the elements of the turbomachine described above and at least one measuring device generally known as an "intrusive meter" because they are immersed in the airflow to be measured, in particular in different areas of the flow channel 19, 20. These areas are commonly called "measurement planes". Indeed, the aerodynamic flow circulating in the channel 19, 20 of the turbomachine 10 has different characteristics in various areas of the flow, for example at the central zone of the flow, along the walls delimiting the flow, upstream of stator blades, etc. Several devices may therefore be necessary for a complete mapping of the flow parameters in the flow 19, 20. [Fig. 1] illustrates different measurement planes of an aircraft turbomachine 10 referenced PL100, PL130, PL310 and PL500.

[0008] A conventional intrusive meter 21 of the "comb" type shown in [Fig. 2] and described in document FR3072169 is equipped with various radial measurement ports. Pressure and temperature measurements are taken simultaneously at different radius values ​​in the airflow of the channel 19, 20. In this case, the meter 21 comprises an elongated body 22 extending along a longitudinal axis X2 and a plurality of measuring nozzles 24 arranged along the body 22. These measuring nozzles 24 incorporate pressure and temperature sensors.

[0009] The body 22 has a leading edge 26, two longitudinal faces originating from the leading edge 26 meet at an edge 27 which constitutes the trailing edge when the measuring device 21 is positioned in the flow channel 19, 20.

[0010] In order to optimize the measurements performed by the intrusive meter 21, it is necessary to choose the positioning of its body 22 with respect to the direction of flow of the gas flow in the channel 19, 20, that is to say the orientation of its leading edge 26 and its trailing edge 27, with respect to the direction of flow of the gas flow in the channel 19, 20. It is known for this to choose an orientation angle of the intrusive meter 21 around its longitudinal axis X2 according to a compromise of the different angles of flow of the gas flow expected in the channel 19, 20 or according to the average angle of flow of the expected gas flow. However, the positioning of the body 22 of the intrusive measuring device 21 cannot be ideal for all gas flow angles or for all engine speeds during which the gas flow varies, thus generating higher uncertainties on the different measurements.

[0011] The optimum uncertainty is obtained along the orientation axis of the intrusive meter 21, that is, when the gas flow direction is oriented from the leading edge 26 to the trailing edge 27 of the intrusive meter 21. However, the gas flow direction is not stable and cannot be determined in advance. Furthermore, when the angle of the gas flow deviates from this direction, the measurement quality degrades, initially gradually and then exponentially. Moreover, it is not possible to correct this effect since the angle of the gas flow orientation is not known in advance and varies with engine speeds.

[0012] Furthermore, to cover measurements at different locations within the turbomachine, it is necessary to provide several intrusive measuring instruments with different orientations depending on the desired positioning within the turbomachine. Indeed, The direction of the average gas flow is not the same everywhere in the turbomachine.

[0013] The present invention proposes a simple, effective and economical solution to the need mentioned above. Summary of the invention

[0014] The invention relates to a test bench for an aircraft turbomachine, comprising an aircraft turbomachine module and at least one intrusive measuring device,

[0015] the turbomachine comprising an annular casing through which a flow of gas is intended to pass,

[0016] the intrusive measuring device comprising a body of elongated shape along an axis and a plurality of measuring nozzles arranged along the body, the body having an aerodynamic profile and being mounted inside the housing, the body comprising a first longitudinal end connected to the housing and a second free longitudinal end opposite the first longitudinal end.

[0017] According to the invention, the first end of the body is connected to the housing so that the body is free to rotate around said axis, thus allowing the body to adopt an automatic position around this axis according to the orientation of said gas flow.

[0018] Thus, according to the invention, the body is mounted to rotate freely about its longitudinal axis, which allows the body to follow the direction of the gas flow, that is, to always orient itself optimally with respect to the gas flow. Indeed, if the angle of the gas flow changes, the pressure of the gas flow on the body will cause the body to rotate about the longitudinal axis of the intrusive meter so as to orient itself parallel to the direction of the gas flow. It is thus understood that the orientation axis of the body, running from its leading edge to its trailing edge, is always parallel to the direction of the gas flow, so as to always obtain optimum measurement quality.

[0019] In other words, the body acts like a weather vane and ensures that it is automatically aligned with the flow of the gas stream.

[0020] The invention thus allows the body to have an optimum automatic positioning regardless of the angle of orientation of the flow of the flows and regardless of the engine speed.

[0021] The present invention thus makes it possible to reduce measurement uncertainty, regardless of the engine operating regime, particularly in the case of multiple mounting or high flow angles.

[0022] Furthermore, it is no longer necessary to provide for several configurations of intrusive measuring device, since thanks to the rotation of the body around the axis, a single configuration The intrusive measuring device can adapt to all positions within the test bench housing.

[0023] Furthermore, aerodynamic studies to modify the intrusive measuring device and the resulting additional mechanical integration studies are no longer necessary.

[0024] The test bench according to the invention may comprise one or more of the following features, taken individually or in combination with each other:

[0025] - the first end of the body is connected to the housing by a guide bearing which extends around the axis;

[0026] - the guide bearing is a rolling bearing;

[0027] - the bearing is a ball bearing;

[0028] - the bearing comprises an outer ring carried by the housing or formed in the casing, and an internal ring carried by the first end of the body or formed on the first end of the body;

[0029] - the first end of the body is connected to a boss on the housing, which extends radially towards the inside of the turbomachine;

[0030] - the first end of the body comprises a portion engaged in a radial orifice passing through the boss;

[0031] - the guide bearing is mounted around the portion and in the orifice of the boss;

[0032] - the first end of the body comprises an external collar bearing on the boss, in a direction parallel to the axis and oriented towards the casing;

[0033] - the first end of the body carries a first element which is capable of cooperating by stop with a second element of the housing in order to axially retain the body vis-à-vis the housing and / or limit the angular travel of the body vis-à-vis the housing around the axis;

[0034] - the first element is a ring or band which is mounted on the body around the axis and which includes at least one leg extending radially with respect to the axis and capable of bearing against the housing, in a direction parallel to the axis and oriented towards the second end of the body, and / or capable of cooperating by way of abutment in a circumferential direction with respect to the axis with stops of the housing;

[0035] - the first end of the body includes a screw thread for a centered nut on the axis and supported by the ring or the ring;

[0036] - the ring or the ring is axially interposed between the guide bearing and the nut;

[0037] - the guide bearing is axially interposed between the ring or the bushing and the collar;

[0038] - the stroke is less than or equal to 20° around the axis;

[0039] - the housing extends around another axis, the axis of the body having a radial orientation in relation to this other axis;

[0040] - the gas flow is intended to flow from upstream to downstream, and the nozzles are oriented downstream. Brief description of the figures

[0041] Other features and advantages will become apparent from the following description of a non-limiting embodiment of the invention with reference to the accompanying drawings in which:

[0042] [Fig-1] [Fig.1], already described, is a schematic partial cross-sectional view of a aircraft turbomachine illustrating different measurement planes in which pressure and temperature readings are taken;

[0043] [Fig.2] The [Fig.2], already described, shows an intrusive measuring device according to the prior art used to perform pressure and temperature measurements in a measurement plane of the turbomachine;

[0044] [Fig. 3] [Fig. 3] is a schematic axial cross-sectional view of an intrusive meter on a turbomachine module according to the invention; and

[0045] [Fig.4] [Fig.4] is a view of a detail of [Fig.3]. Detailed description of the invention

[0046] Identical, similar, or analogous elements retain the same reference numeral from one figure to another. Furthermore, the terms "upstream" and "downstream" are understood by reference to the direction of gas flow within the turbomachine. The gas flow is intended to move from upstream to downstream.

[0047] The invention relates to a test bench for an aircraft turbomachine 10 as illustrated in [Fig.1], comprising an aircraft turbomachine module 1 comprising all or part of the elements of the turbomachine 10.

[0048] The test bench further comprises an intrusive measuring device 21 such as, for example, the one illustrated in [Fig. 3]. Such an intrusive measuring device 21 includes, in particular, a body 22. The intrusive measuring device 21 includes, for example, a plurality of measuring nozzles 24 incorporating, in particular, pressure and temperature measuring sensors. The intrusive measuring device 21 can, for example, be positioned inside the secondary flow channel 20 at the level of the blower 11 (see [Fig. 1]). The body 22 is, for example, mounted inside the housing 14, 16 and has, in particular, an aerodynamic profile.

[0049] More specifically, the elongated body 22 extends along a longitudinal axis X2. In the following description, the notions of longitudinal, axial, radial, and internal or external, are relative to this longitudinal axis X2 except when it is mentioned that reference is being made to the longitudinal axis XI of the turbomachine.

[0050] Thus, the housing 14, 16 extends around the axis XI of the turbomachine, and the longitudinal axis X2 of the body 22 has in particular a radial orientation with respect to this other axis XI of the turbomachine.

[0051] The body 22 has a leading edge 26, for example, rounded in shape, particularly in the form of a portion of a cylinder. Two longitudinal faces extending from the leading edge 26 meet at an edge 27, which constitutes the trailing edge 27 when the meter 21 is positioned in the flow stream. Thus, the trailing edge 27 is located sufficiently far downstream to prevent the airflow from separating. The radial axis R extending from the leading edge 26 to the trailing edge 30 is designated by the orientation axis R of the body 22, and the radial extension of the body is the extension of the body 22 along this orientation axis R. The body 22 has, for example, a first longitudinal end 31 connected to the housing 14, 16, and in particular a second free longitudinal end 32 opposite the first longitudinal end 31.

[0052] The measuring nozzles 24 are for example arranged along the body 22 at the level of the leading edge 26. The nozzles 24 are oriented downstream.

[0053] The measuring nozzles 24 extend outward from the body 22. The temperature sensors associated with the measuring nozzles 24 may be in the form of thermocouple sensors. The pressure sensors may consist of instrumentation tubes, such as Kiel probes. The sensing elements of the sensors extend beyond the body 22 at the leading edge 26. The sensors are connected to a computer (not shown) that processes the measured data via instrumentation lines.

[0054] Advantageously, the body 22 includes a hollow portion 28 to allow for the routing of instrumentation lines (not shown) inside the body 22. The body 22 may be made of a metallic or ceramic material. The body 22 may be made in one or more parts.

[0055] According to the invention, the first end 31 of the body 22 is connected to the housing 14, 16 in such a way that the body 22 is free to rotate about the longitudinal axis X2, thus allowing the body 22 to automatically adopt a position about this longitudinal axis X2 according to the orientation F of the gas flow. It is understood here that the gas flow exerts pressure on the body 22, causing it to rotate about the longitudinal axis X2 until the orientation of the body 22 is parallel to the orientation F of the gas flow, that is, until the axis R is parallel to the orientation F of the gas flow. The body 22 is thus always in the optimum position with respect to the orientation F of the gas flow, thereby optimizing the measurement quality of the intrusive meter 21.

[0056] The first end 31 of the body 22 is connected to the housing 14, 16 by a guide bearing 40 (also visible [Fig. 4]) which extends around the longitudinal axis X2 allowing in particular rotation about the longitudinal axis X2. The guide bearing 40 is for example a roller bearing 40. The roller bearing 40 is in particular a ball bearing 40. The ball bearing 40 allows the body 22 to be connected to the housing 14, 16 so that the body 22 is free to rotate about the longitudinal axis X2 while being fixed relative to the housing in the other directions.

[0057] The bearing 40 includes, for example, an outer ring 41 carried by the housing 14, 16 or, as illustrated in [Fig. 3], formed in the housing 14, 16. The bearing 40 includes, in particular, an inner ring 42 formed by the first end 31 of the body 22 or, as illustrated in [Fig. 3], carried on the first end 31 of the body 22. The bearing 40 includes, in particular, balls 43, located, for example, between the outer ring 41 and the inner ring 42, and allowing, in particular, the rotation of the body 22 around the longitudinal axis X2 relative to the housing 14, 16.

[0058] The first end 31 of the body 22 is connected to a boss 50 of the housing 14, 16, which extends radially into the interior of the turbomachine. The boss 50 is circular in shape. The boss 50 includes, in particular, a radial through-hole 51. The intrusive meter 21 of the invention can be mounted on any type of turbomachine boss 50.

[0059] The first end 31 of the body 22 includes a portion 33 engaged in particular in the radial orifice through 51. The portion 33 is in particular cylindrical in shape.

[0060] The guide bearing 40 is in particular mounted around the portion 33 and in the orifice 51 of the boss 50. The outer ring 41 is in particular formed in the boss 50 of the housing 14, 16.

[0061] The first end 31 of the body 22 includes in particular an external collar 34. The external collar 34 is in particular supported on the boss 50, in a direction parallel to the longitudinal axis X2 and oriented towards the housing 14, 16. The external collar 34 is in particular circular and surrounds in particular the body 22. The external collar 34, for example, protrudes radially from the rest of the body 22.

[0062] The first end 31 of the body 22 carries for example a first element 70 which is in particular able to cooperate by stop with a second element 80 of the housing 14, 16 in order to axially retain the body 22 vis-à-vis the housing 14, 16 and / or limit the angular stroke of movement of the body 22 vis-à-vis the housing 14, 16 around the longitudinal axis X2.

[0063] The first element 70 is in particular a ring 70 or a bushing 70 which is mounted on the body 22 around the longitudinal axis X2. The first element 70 includes in particular at least one tab 71 extending radially with respect to the longitudinal axis X2. The tab 71 is in particular adapted to bear against the housing 14, 16, in a direction parallel to the longitudinal axis X2 and, for example, in a direction oriented towards the second end 32 of the body 22. The leg 71 is particularly suited to cooperate by means of a circumferential stop with respect to the longitudinal axis X2 with stops 81 of the housing 14, 16. The housing 14, 16 comprises, for example, two stops 81 (only one is visible [Fig. 3] and 4). The leg 71 can move angularly around the longitudinal axis X2 between these two stops 81 so as to limit the angular travel of the body 22 around the longitudinal axis X2 by a corresponding angle. The travel is less than or equal to 20° around the longitudinal axis X2.

[0064] The first end 31 of the body 22 includes a thread 35 for screwing a nut 36 centered on the longitudinal axis X2 and bearing against the ring 70. The nut 36 is screwed onto the thread 35 of the first end 31, in particular until it comes into contact with the ring 70. The ring 70 is, for example, axially interposed between the guide bearing 40 and the nut 36, and more particularly between the inner ring 42 of the guide bearing 40 and the nut 36.

[0065] The guide bearing 40 is in particular axially interposed between the ring 70 and the flange 34. More particularly, it is the inner ring 42 which is axially interposed between the ring 70 and the flange 34. The flange 34 includes, for example, a rim 37 on which the guide bearing 40 rests.

[0066] Thus, when the nut 36 is screwed onto the thread 35, it is tightened against the ring 70, which is itself tightened against the guide bearing 40 on one side and against the housing 14, 16 via its first element 71 in an axial orientation going towards the second end 32 on the other side. The guide bearing 40 is clamped against the body 22, and in particular the outer flange 34, the latter being clamped against the boss 50 of the housing 14, 16, in an axial orientation directed towards the first end 31, that is to say, an orientation opposite to that of the support of the first element 71 against the housing 14, 16. The intrusive measuring device 21 is thus fixed axially with respect to the housing 14, 16, notably by axially sandwiching the housing 14, 16 and in particular its boss. Specifically, it is the first element 71 on the one hand and the flange 34 on the other hand that axially sandwich the boss 50 of the housing 14, 16.

Claims

Demands

1. Test bench for an aircraft turbomachine (10), comprising an aircraft turbomachine module (1) and at least one intrusive meter (21), the turbomachine (10) comprising an annular housing (14, 16) through which a gas flow is intended to pass, the intrusive meter (21) comprising a body (22) elongated along an axis (X2) and a plurality of measuring nozzles (24) arranged along the body (22), the body (22) having an aerodynamic profile and being mounted inside the housing (14, 16), the body (22) comprising a first longitudinal end (31) connected to the housing (14, 16) and a second free longitudinal end (32) opposite the first longitudinal end (31), characterized in that the first end (31) of the body (22) is connected to the housing (14,16) so that the body (22) is free to rotate about said axis (X2), thus allowing the body (22) to automatically adopt a position about this axis (X2) according to the orientation of said gas flow.

2. Test bench according to claim 1, wherein the first end (31) of the body (22) is connected to the housing (14, 16) by a guide bearing (40) which extends around the axis (X2).

3. Test bench according to claim 2, wherein the guide bearing (40) is a rolling bearing (40).

4. Test bench according to claim 3, wherein the rolling bearing (40) is a ball bearing (40).

5. Test bench according to claim 3 or 4, wherein the bearing (40) comprises an outer ring (41) carried by the housing (14, 16) or formed in the housing (14, 16), and an inner ring (42) carried by the first end (31) of the body (22) or formed on the first end (31) of the body (22).

6. Test bench according to any one of the preceding claims, wherein the first end (31) of the body (22) is connected to a boss (50) of the casing (14, 16), which extends radially into the interior of the turbomachine (10).

7. Test bench according to claim 6, wherein the first end (31) of the body (22) comprises a portion (33) engaged in a radial through orifice (51) of the boss (50).

8. Test bench according to claim 7, depending on claim 6 and any one of claims 2 to 5, in which the guide bearing (40) is mounted around the portion (33) and in the orifice (51) of the boss (50).

9. Test bench according to any one of claims 6 to 8, wherein the first end (31) of the body (22) comprises an external collar (34) bearing on the boss (50), in a direction parallel to the axis (X2) and oriented towards the housing (14, 16).

10. Test bench according to any one of the preceding claims, wherein the first end (31) of the body (22) carries a first element (70) which is able to cooperate by buttock with a second element (80) of the housing (14, 16) in order to axially retain the body (22) vis-à-vis the housing (14, 16) and / or limit the angular stroke of deflection of the body (22) vis-à-vis the housing (14, 16) around the axis (X2).

11. Test bench according to claim 10, wherein the first element (70) is a ring (70) or a ring (70) which is mounted on the body (22) around the axis (X2) and which includes at least one lug (71) extending radially with respect to the axis (X2) and adapted to bear against the housing (14, 16), in a direction parallel to the axis (X2) and oriented towards the second end (32) of the body (22), and / or adapted to cooperate by butting in a circumferential direction with respect to the axis (X2) with stops (81) of the housing (14, 16).

12. Test bench according to claim 11, wherein the first end (31) of the body (22) includes a screw thread (35) for a nut (36) centered on the axis (X2) and bearing on the ring (70) or the ring (70).

13. Test bench according to claim 12, depending on any one of claims 2 to 5 and 8, wherein the ring (70) or the ring (70) is axially intercalated between the guide bearing (40) and the nut (36).

14. Test bench according to claim 13, depending on claim 9, in which the guide bearing (40) is axially interposed between the ring (70) or the ring (70) and the collar (34).

15. Test bench according to any one of claims 10 to 14, wherein the stroke is less than or equal to 20° around the axis (X2).