Assembly comprising a device for measuring the flow rate of an aerodynamic leak from an aeronautical turbomachine casing

Abstract

This assembly comprises: an aeronautical turbomachine casing, the casing delimiting a flow path and exhibiting a leak; at least one flow measurement device (9) for the aerodynamic flow corresponding to the leak, including means for acquiring information (11) representative of the flow rate; a body (12) carrying the means for acquiring information (11); and connecting means (13) attached to a first end (14) of the body (12), configured to removably fix the measuring device (9) to a wall of the casing on a side opposite the flow path. The body (12) includes a bell (15) forming a flow receiving chamber, the bell (15) being provided with an outlet orifice (17) so as to allow the flow to be evacuated to the outside of the chamber through the outlet orifice (17). Figure 2 for the abbreviated version.

Description

Title of the invention: Assembly comprising a device for measuring the flow rate of an aerodynamic leak from an aeronautical turbomachine casing. Technical field

[0001] The invention relates to the field of leakage flow measurement devices for a turbomachine housing. Previous techniques

[0002] In the context of the development of turbomachinery, and in particular turbomachinery for aircraft, these undergo a multitude of verification tests to validate their proper functioning and their ability to maintain their integrity and performance.

[0003] For example, in the presence of an identified air leak on a turbomachine housing, it is necessary to estimate the air flow associated with this leak, in order to allow an estimation of its impact on the performance of the turbomachine.

[0004] As is known, the air flow rate of the leak can be estimated from a leak cross-section value that is not directly measurable but can be estimated. This first method is very imprecise, because the estimate of the leak cross-section is subject to a high degree of uncertainty, often equal to plus or minus 100% of the actual leak cross-section.

[0005] An alternative method consists of estimating the leak rate by an enthalpy balance based on temperature measurements, particularly downstream of the leak. This second method does not offer any significant improvement, as it suffers from a level of inaccuracy similar to that of the first method. Description of the invention

[0006] In view of the foregoing, the invention aims to provide a device for measuring the flow rate of an aerodynamic leak from a turbomachine casing with improved measurement accuracy.

[0007] The proposed measuring device also aims to ensure rapid installation and removal of the measuring device so as not to delay the deadlines of the testing and trial period.

[0008] The invention relates to an assembly comprising an aircraft turbomachine casing delimiting an aerodynamic channel and exhibiting a leak.

[0009] The assembly also includes at least one device for measuring the flow rate of an aerodynamic flow corresponding to the leak. The measuring device comprises: - means of collecting information representative of the aerodynamic flow rate, - a body carrying the means of gathering information, and - connecting means attached to a first end of the body, configured to removably fix the measuring device to a wall of the casing on a side opposite to the vein.

[0010] The body includes a bell forming a chamber for receiving the aerodynamic flow, the bell being provided with an outlet orifice so as to allow the evacuation of the aerodynamic flow to the outside of the chamber through the outlet orifice.

[0011] Such a configuration ensures the capture of the aerodynamic flow of the leak and its redirection to flow measurement means, thus enabling improved measurements. The removable attachment of such a measuring device facilitates installation and removal, allowing for the efficient measurement of flow rates of instrumentation leaks, for example, around measuring probes or leaks around screw threads.

[0012] Preferably, the bell comprises an edge provided with a sealing means that comes into contact with the housing wall. Such a sealing means ensures a seal between the bell and the housing wall.

[0013] Advantageously, the sealing means is configured so as to be compressed by a predetermined amount when the measuring device is fixed to the housing wall by the connecting means. Such compression increases the quality of the seal.

[0014] For example, the sealing means includes a toroidal section seal, an omega profile seal, or a rectangular or square section seal.

[0015] According to one feature, the body comprises a pipe attached to the bell downstream of the outlet orifice, the pipe being in fluidic communication with the chamber and receiving the entire aerodynamic flow passing through the chamber. Such a configuration allows for controlled exit of the aerodynamic flow from the chamber.

[0016] Advantageously, the pipe is straight, has a constant cross-section and carries the means for collecting information.

[0017] Preferably, the connecting means include at least one magnet disposed on a shoulder of the bell and coming into contact with the wall of the housing with a predetermined connecting force so as to ensure a removable connection between the measuring device and the wall of the housing.

[0018] According to another feature, the connecting means comprise several magnets evenly distributed around a circumference of the bell shoulder. A This configuration allows for uniform compression of the sealing medium and contributes to the durability of the measuring device.

[0019] For example, the means for collecting information include an anemometer or a flowmeter operating by pressure difference.

[0020] According to another aspect, the invention relates to an aeronautical turbomachine comprising an assembly as defined above. Brief description of the drawings

[0021] Other objects, features and advantages of the invention will become apparent from the following description, given solely by way of non-limiting example, and made with reference to the accompanying drawings in which:

[0022] [Fig. 1] is a partial cross-sectional view of a turbomachine equipped with a flow measurement device for a leak from a turbomachine casing according to the invention;

[0023] [Fig.2] is a front perspective view of the measuring device of the [Fig.1];

[0024] [Fig.3] is a perspective view from below of the measuring device of [Fig.1], and

[0025] [Fig.4] is a cross-sectional view of the measuring device along axis IV-IV of [Fig.2] fixed to a wall of the turbomachine housing of [Fig.1]. Detailed description of at least one embodiment

[0026] Figure 1 shows a partial cross-sectional view of a turbomachine with longitudinal axis X, in particular a turbofan aircraft turbomachine according to the invention. Of course, the invention is not limited to this type of turbomachine.

[0027] The double-flow turbomachine 1 generally comprises a low-pressure gas compressor 2 and a high-pressure gas compressor 3 upstream of which a blower 4 is mounted. In the present invention, and generally, the terms "upstream" and "downstream" are defined with respect to the flow of gases in the turbomachine along the longitudinal axis X.

[0028] The turbomachine 1 comprises a primary annular vein 5 and a secondary annular vein 6. The primary veins 5 and secondary veins 6 are coaxial.

[0029] In the primary vein 5, a primary flow or hot flow circulates which passes from upstream to downstream through the low pressure compressor 2 and the high pressure compressor 3.

[0030] In the secondary channel 6, a secondary flow or cold flow circulates around the compressors 2, 3. In particular, the secondary channel 6 is radially delimited by a blower housing 7 and an internal housing 8, in which the low- and high-pressure compressors are housed. The term "radial" is defined with respect to a radial axis substantially perpendicular to the longitudinal axis X.

[0031] At least one flow measurement device 9 for an aerodynamic flow of a leak, as illustrated in [Fig.2], [Fig.3] and [Fig.4], is installed on a wall 10 of a housing 8 so as to allow a flow measurement of an aerodynamic flow of Leak, corresponding to a gas leak through wall 10 from the primary vein 5 or from the secondary vein 6. It should be noted that identical or similar elements bear the same reference numerals from one figure to another. As is known, leak identification and location are achieved by blowing with talc or by using a thermocouple.

[0032] The measuring device 9 includes means for collecting information 11 representative of the flow rate and a body 12 carrying the means for collecting information 11.

[0033] The measuring device 9 further comprises connecting means 13 attached to a first end 14 of the body 12 configured to removably fix the measuring device 9 to the wall 10 of the housing 8, on a side opposite the primary 5 originating the aerodynamic flow. Alternatively, the measuring device 9 can be installed on the fan housing 7 to measure the leakage rate of an aerodynamic flow escaping through a wall 7a of the housing 7 from the secondary duct 6. In this case, the connecting means 13 ensure the removable fixing of the measuring device 9 to the wall 7a of the housing 7, on the side opposite the secondary duct 6.

[0034] The body 12 comprises a bell 15 forming a chamber 16 for receiving the aerodynamic flow corresponding to the leak, particularly visible in [Fig. 3] and [Fig. 4]. The chamber 16 is provided with an outlet orifice 17 so as to allow the aerodynamic flow to be evacuated to the outside of the chamber 16 through the orifice 17. Due to the leak, a small portion dF of the flow F from the vein 5 passes into the chamber 16 and constitutes an inflow Fe ([Fig. 4]). The outflow from the chamber 16, referenced Fs, is equal to the inflow Fe. The outflow Fs is found in its entirety at the outlet of the pipe 18.

[0035] In the embodiment illustrated in Figures 2 to 4, chamber 16 has a cylindrical shape. Alternatively, chamber 16 may have a different shape, for example cubic.

[0036] Here, the body 12 includes a pipe 18 attached to the bell 15 downstream of the outlet orifice 17. The pipe 18 is in fluidic communication with the chamber 16 and receives the entire aerodynamic flow passing through the chamber 16. Preferably, the data collection means 11 are carried by the pipe 18, which is straight and has a constant cross-section. The cross-sectional size of the pipe 18 is chosen so as not to impede the evacuation of the aerodynamic flow. Advantageously, the pipe 18 can be arranged so as not to direct the outgoing flow towards sensitive areas of the housing 8.

[0037] Preferably, the data collection means 11 include means for actually measuring the flow rate or average velocity through the pipe section 18. For example, the data collection means 11 may include an anemometer or a flow meter operating by pressure difference. More generally, the means of data acquisition 11 may include any other known flow measurement system compatible with the intended application.

[0038] As particularly visible in [Fig.3] and [Fig.4], the bell 15 includes an edge 19 provided with a sealing means 20 which comes into contact with the wall 10 of the housing 8 so as to ensure sealing between the bell 15 and the wall 10. Preferably, the sealing means 20 includes a sealing O-ring with a Shore A hardness ranging from 60 to 80. Alternatively, it is possible to use a sealing gasket of a different shape, for example a flat gasket, an omega profile gasket or a gasket with a rectangular or square cross-section.

[0039] The sealing means ensures that the flux Fe received in chamber 16 is equal to the outgoing flux Fs from chamber 16 through outlet 17. In this way, the aerodynamic flux corresponding to the leak is entirely directed towards the data collection means 11.

[0040] Preferably, the sealing means 20 is configured so as to be crushed by a predetermined value when the measuring device 9 is fixed to the wall 10 of the housing 8 by the connecting means 13. For example, the crushing of the sealing means 20 may correspond to a deformation ranging from 10% to 30% of the dimension before crushing.

[0041] The linking means 13 comprise at least one magnet disposed on a shoulder 21 of the bell 15 and coming into contact with the wall 10 of the housing 8 with a predetermined linking force so as to ensure a removable link between the measuring device 9 and the wall 10 of the housing 8. By way of example, the magnets can generate a total linking force on the order of several hundred newtons.

[0042] According to the embodiment illustrated in [Fig.3], the connecting means 13 comprise several magnets, here three in number, distributed uniformly over a circumference of the shoulder 21. Alternatively, it is of course possible to provide a different number of magnets.

Claims

Demands

1. Assembly comprising: - a turbomachine (1) aircraft casing (7,8), the casing (7,8) delimiting an aerodynamic channel (5, 6) and having a leak, - at least one flow measurement device (9) for the aerodynamic flow corresponding to the leak, comprising means for recording information (11) representative of the flow rate of the aerodynamic flow, a body (12) carrying the means for recording information (11), and connecting means (13) integral with a first end (14) of the body (12) and configured to removably fix the measuring device (9) to a wall (7a, 10) of the casing (7, 8) on a side opposite the channel (5, 6), the assembly being characterized in that the body (12) comprises a bell (15) forming a chamber (16) for receiving the aerodynamic flow,the bell (15) being provided with an outlet orifice (17) so as to allow the evacuation of the aerodynamic flow to the outside of the chamber (16) through the outlet orifice (17).

2. Assembly according to claim 1, wherein the bell (15) includes an edge (19) provided with a sealing means (20) coming into contact with the wall (7a, 10) of the housing (7, 8).

3. Assembly according to claim 2, wherein the sealing means (20) is configured so as to be crushed by a predetermined value when the measuring device (9) is fixed to the wall (7a, 10) of the housing (7, 8) by the connecting means (13).

4. Assembly according to claim 2 or 3, wherein the sealing means (20) comprises a toroidal section seal, an omega profile seal, or a rectangular or square section seal.

5. Assembly according to any one of claims 1 to 4, wherein the body (12) comprises a pipe (18) attached to the bell (15) downstream of the outlet port (17), the pipe (18) being in fluidic communication with the chamber (16) and receiving the entirety of the aerodynamic flow passing through the chamber (16).

6. Assembly according to claim 5, wherein the pipe (18) is straight, has a constant cross-section and carries the information-gathering means (H).

7. Assembly according to any one of claims 1 to 6, wherein the connecting means (13) comprise at least one magnet disposed on a shoulder (21) of the bell (15) and coming into contact with the wall (7a, 10) of the housing (7, 8) with a predetermined connecting force so as to ensure a removable connection between the measuring device (9) and the wall (7a, 10) of the housing (7, 8).

8. Assembly according to claim 7, wherein the connecting means (13) comprise several magnets distributed uniformly over a circumference of the shoulder (21) of the bell (15).

9. Assembly according to any one of claims 1 to 8, wherein the information-gathering means (11) comprise an anemometer or a flowmeter operating by pressure difference.

10. Aeronautical turbomachine (1) comprising an assembly according to any one of claims 1 to 9.

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