AIRCRAFT PROVIDED WITH A HEATING SYSTEM FOR A TURBOSHAFT ENGINE PLENUM

Abstract

An aircraft provided with a turboshaft engine comprising a gas generator, the gas generator comprising a compression assembly supplying air to a combustion chamber and a turbine assembly supplied with gas by the combustion chamber, the aircraft having a plenum supplying air to the compression assembly. The aircraft comprises a heating system, the heating system comprising a heat exchanger arranged in the plenum, the heating system comprising a fluid supply connection and a fluid discharge connection connected to the heat exchanger, the fluid supply connection conveying hot air from the turboshaft engine into the heat exchanger.

Claims

1. An aircraft provided with a turboshaft engine comprising a gas generator, the gas generator comprising a compression assembly supplying compressed air to a combustion chamber, the gas generator comprising a turbine assembly supplied with gas by the combustion chamber, the aircraft having an air supply system with a radial intake provided with a plenum supplying air to the compression assembly, the plenum comprising a duct provided with an outer opening leading to an outside environment situated outside the aircraft, wherein the aircraft comprises a heating system, the heating system comprising a heat exchanger arranged in a volume delimited by the plenum, the heating system comprising a fluid supply connection and a fluid discharge connection connected to the heat exchanger, the fluid supply connection conveying hot air from the turboshaft engine into the heat exchanger.

2. The aircraft according to claim 1, wherein the turboshaft engine comprises a gas stream extending from the plenum and passes successively through the compression assembly, then the combustion chamber and the turbine assembly, the fluid supply connection being in fluidic connection with the gas stream downstream of a compression stage of the compression assembly.

3. The aircraft according to claim 1, wherein the fluid supply connection and the fluid discharge connection pass through the same wall of the plenum to reach an engine compartment of the aircraft, the turboshaft engine being at least partially housed in this engine compartment.

4. The aircraft according to claim 1, wherein the fluid discharge connection leads to an engine compartment of the aircraft, the turboshaft engine being at least partially housed in this engine compartment.

5. The aircraft according to claim 1, wherein the heat exchanger comprises two walls separated by studs, the hot air flowing between the two walls.

6. The aircraft according to claim 5, wherein the heat exchanger has a central deflector providing a U-shaped path between the two walls, this path leading from the fluid supply connection to the fluid discharge connection in a direction of flow of the hot air.

7. The aircraft according to claim 1, wherein the heating system comprises one or more fastenings securing the heat exchanger to the plenum, the heat exchanger not being in contact at least with a bottom of the plenum.

8. The aircraft according to claim 1, wherein the fluid supply connection comprises a solenoid valve arranged between two pipes, the solenoid valve being configured to allow or to prevent the hot air to be conveyed into the heat exchanger.

9. The aircraft according to claim 1, wherein the fluid supply connection comprises a narrowing forming a flow limiter.

10. The aircraft according to claim 1, wherein the heating system comprises a pressure sensor connected to an alerter.

11. The aircraft according to claim 1, wherein the plenum comprises at least one drain.

12. The aircraft according to claim 1, wherein the air supply system is a passive system ingesting air from the outside environment under the effect of suction from the turboshaft engine.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0054] The disclosure and its advantages appear in greater detail in the context of the following description of embodiments given by way of illustration and with reference to the accompanying figures, wherein:

[0055] FIG. 1 is an outside view of an aircraft according to the disclosure;

[0056] FIG. 2 is a cross-sectional diagram of a plenum of an aircraft according to the disclosure;

[0057] FIG. 3 is a diagram showing the heating system of the disclosure; and

[0058] FIG. 4 is a three-dimensional view of a heating system of the disclosure.

DETAILED DESCRIPTION

[0059] Elements that are present in more than one of the figures are given the same references in each of them.

[0060] FIG. 1 shows an aircraft 1 according to the disclosure. This aircraft 1 comprises an airframe 2 extending in the direction of forward travel 500 of the aircraft from a rear end 4 towards a nose 3.

[0061] The aircraft 1 comprises a power plant provided with an air supply system with a radial intake provided with a plenum 40 having a radial outer opening 41 for supplying a turboshaft engine. The term radial refers to a direction orthogonal to a central axis along which the turboshaft engine extends. For example, the turboshaft engine sets a power transmission system 35 in motion, this power transmission system 35 being able to set in motion at least one rotor 5,6 contributing to the propulsion and/or the lift of this aircraft 1 and/or helping to control this aircraft 1. For example, the aircraft 1 is a helicopter provided with a main rotor 5 contributing to its lift and propulsion, and a tail rotor 6 helping to control the yaw motion of the aircraft 1.

[0062] In reference to FIG. 2, the plenum 40 comprises a duct 46 provided with an outer opening 41 leading to an environment EXT outside the aircraft, and an inner opening 42 leading to an air intake of a turboshaft engine 10. The duct 46 may be described as annular insofar as it extends radially from the outer opening 41 towards the inner opening 42. In order to delimit the duct 46, the plenum 40 may comprise two partitions 43, 44, not shown in FIG. 2, that are connected by an edge section 45, that is, for example, substantially arc-shaped.

[0063] In reference to FIG. 3, the turboshaft engine 10 is arranged at least partially in an engine compartment 9. This engine compartment 9 may lead to an outlet nozzle 90, the air present in the engine compartment 9 being sucked into the outlet nozzle 90 during operation.

[0064] The turboshaft engine 10 comprises a gas generator 15. The gas generator 15 is provided with a compression assembly 20 supplied with cool air by the plenum 40. For example, the compression assembly 20 comprises one or more compression stages 21, 23. The example provided shows a compression assembly 20 provided with a first compression stage 21 constrained to rotate with a second compression stage 23, via a shaft 22.

[0065] Downstream of the compression assembly 20, in the direction of flow of the gases in the turboshaft engine 10, the gas generator 15 comprises a combustion chamber 24, then a turbine assembly 25. The turbine assembly 25 is set in motion by the gases exiting the combustion chamber 24, and is constrained to rotate with the compression assembly 20. The turbine assembly 25 may comprise at least one turbine. Finally, the turboshaft engine 10 comprises at least one power turbine 30, for example connected to the power transmission system 35 disclosed above.

[0066] The turboshaft engine 10 comprises a gas stream 26 that starts from the plenum 40, passes through the vanes of the compression stages 22, 23, and then through the combustion chamber 24, the vanes of the turbine or turbines of the turbine assembly 25 and lastly the vanes of the working turbine or turbines 30.

[0067] The aircraft 1 comprises a heating system 50 for minimizing the accumulation of ice and/or snow in the plenum 40. The heating system 50 may be a de-icing system for limiting the formation of ice and snow to a level that is acceptable for the turboshaft engine 10.

[0068] This heating system 50 comprises a heat exchanger 60 arranged in the volume 47 delimited by the plenum 40, i.e., inside the plenum 40, not inside a wall of the plenum 40.

[0069] For example, the heating system 50 comprises one or more fastenings 85 each securing the heat exchanger 60 to the plenum 40. For example, the heat exchanger is fastened by two fastenings to two respective partitions 43, 44 and by two other fastenings to the edge section 45.

[0070] The heat exchanger 60 is possibly secured to the plenum 40 in such a way as not to be in contact with the plenum 40, in particular being separated by a clearance at least from a bottom 400 of the plenum 40, and possibly also from the partitions 43, 44. Therefore, a clearance 300, for example in the region of 8 to 10 millimeters, separates the heat exchanger 60 from the bottom 400 of the plenum 40 in order to allow air to flow under the heat exchanger 60 and, more specifically, between the heat exchanger 60 and the plenum 40. The bottom of the plenum may comprise a part of the plenum that is situated below the heat exchanger, when the aircraft is not performing a rollover and/or, for example, when the aircraft is resting on flat ground.

[0071] Moreover, the heating system 50 comprises a fluid supply connection 70 for fluidically connecting the heat exchanger 60 and the gas stream 26. For example, the fluid supply connection 70 is in fluidic connection with the gas stream 26 downstream of a compression stage of the compression assembly 20, or even of the compression stage 23 situated before the combustion chamber, in order to draw off hot compressed air.

[0072] This fluid supply connection 70 may comprise one or more pipes 71, 72. The term pipe denotes one or more pipings for circulating the hot gases that have been drawn off.

[0073] The fluid supply connection 70 may comprise a solenoid valve 75 connected by a first pipe 71 to the heat exchanger 60 and by a second pipe 72 to a pressure connector 73 of the turboshaft engine 10. The solenoid valve 75 may be controlled by a human-machine interface 750. The solenoid valve 75 may be a two-position valve for either preventing hot gases from flowing to the heat exchanger 60 or allowing hot gases to flow to the heat exchanger 60.

[0074] The fluid supply connection 70 may comprise a pressure sensor 81, downstream of the solenoid valve 75 if any. The pressure sensor 81 is connected to an alerter 82 by a wired or wireless link. The pressure sensor 81 may, for example, transmit an analog, digital, electrical or optical signal to the alerter 82 when the pressure in the fluid supply connection 70 is greater than or equal to a threshold, or conversely when the pressure in the fluid supply connection 70 is less than the threshold. The generated alert may be in the form of a visual alarm, for example emitting a light with a light-emitting diode or an equivalent or one or more characters being displayed on a screen, an audible alarm, via a loudspeaker, and/or a haptic alarm, for example by means of a vibrating unit causing a member held or worn by an individual to vibrate.

[0075] The fluid supply connection 70 may comprise at least one narrowing 76 formant a flow limiter. In the example shown, a narrowing 76 is located downstream of the solenoid valve 75. Alternatively, or additionally, a narrowing 76 may be located upstream of the solenoid valve 75, for example on the pipe 72, in order to limit the speed of the air in the solenoid valve 75, or also upstream of the pipe 72.

[0076] Moreover, the heating system 50 further comprises a fluid discharge connection 80 for discharging the hot air passing through the heat exchanger 60. For example, the fluid discharge connection 80 leads into the engine compartment 9.

[0077] In reference to FIG. 4, the fluid supply connection 70 and the fluid discharge connection 80 may pass through the same wall 44 of the plenum 40 to reach the engine compartment 9.

[0078] According to another aspect, the heating system 50 may comprise at least one support 94 connecting the fluid supply connection 70 or the fluid discharge connection 80 either to the plenum 40 or to a load-bearing structure, that is not shown, of the aircraft 1.

[0079] To this end, the heat exchanger 60 may comprise an internal space delimited by two walls 61, 62, and a peripheral edge 63 connecting the two walls 61, 62. These two walls 61, 62 may comprise a top wall 61 and a bottom wall 62 situated under the top wall 61, at least when the aircraft 1 is resting via a landing gear on substantially horizontal ground. The top wall 61 and the bottom wall 62 may be parallel to each other and/or substantially parallelepiped in shape, or indeed identical. The fluid supply connection 70 and the fluid discharge connection 80 are each connected to one of the two walls 61, 62 in order to make the hot air flow through the internal space. For example, the fluid supply connection 70 and the fluid discharge connection 80 may be connected to the same wall, and more specifically to the top wall 61, in the example shown in FIG. 4.

[0080] According to another aspect, the heat exchanger 60 may comprise a central deflector 65, for example comprising a partition, that may be straight, arranged between the two walls 61, 62. The central deflector 65 forms a U-shaped path 66 for the hot air between the two walls 61, 62. This path 66 extends from the fluid supply connection 70 to the fluid discharge connection 80. Therefore, the fluid supply connection 70 and the fluid discharge connection 80 may be arranged on the same side of the heat exchanger 60, according to a lengthwise direction wherein this heat exchanger 60 extends.

[0081] According to another aspect, the plenum 40 may comprise at least one drain 96. For example, at least one drain 96 is provided on a wall opposite the heat exchanger 60, or indeed situated under the heat exchanger 60. For example, the plenum comprises four drains 96 situated at four corners of the plenum.

[0082] Therefore, when the aircraft 1 is flying in icing conditions, if necessary, a pilot maneuvers the human-machine interface to open the solenoid valve 75. The hot air circulating in the compression assembly 20 of the turboshaft engine 10 automatically flows into the fluid supply connection 70. If applicable, the pressure sensor 81 detects a change in pressure and transmits a signal to the alerter 82, that issues an alert.

[0083] The hot air then flows into the heat exchanger 60, and is then discharged into the engine compartment 9 by the fluid discharge connection 80. The walls 61, 62 of the heat exchanger 60 heat up and tend to heat up the plenum 40. Any ice, snow or water present in the bottom of the plenum 40 flows through a drain 96 out of the plenum 40.

[0084] Naturally, the present disclosure is subject to numerous variations as regards its implementation. Although several embodiments are described above, it should readily be understood that it is not conceivable to identify exhaustively all the possible embodiments. It is naturally possible to replace any of the means described with equivalent means without going beyond the ambit of the present disclosure.