Nacelle for gas turbine engine

Abstract

A nacelle for a gas turbine engine includes an inner portion in a radial direction of the gas turbine engine and a heat exchanger. The inner portion defines a heat exchanger conduit including an inlet and an outlet. A heat exchanger is disposed in the heat exchanger conduit between the inlet and the outlet. The inlet is disposed rearward of the outlet along a central axis of the nacelle.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Polish patent application serial number P.446464 filed on October 23, 2023. Technical Field

[0003] The present invention relates to a nacelle for a gas turbine engine, and in particular to a heat exchanger for a nacelle of an aircraft engine. Background Art

[0004] Aircraft engines use air-cooled heat exchanger systems to cool various other components of the engine. The pressure difference between the opposite sides of the heat exchanger drives the air flow through the heat exchanger. This pressure difference may be caused by dynamic head pressure, pressurized volume relative to the environment, and / or different fluid flows within the engine. There is still an opportunity to use components of the engine to better control these pressure differences, thereby making it easier to utilize the heat exchanger by increasing the air flow through the heat exchanger. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] A full and enabling disclosure of the present invention, including the best mode thereof, is set forth in the specification to those skilled in the art, with reference to the accompanying drawings, wherein:

[0006] Figure 1 is a cross-sectional view of an exemplary turbofan gas turbine engine.

[0007] Figure 2 yes Figure 1 An enlarged view of a portion of a nacelle of a gas turbine engine, including heat exchanger piping.

[0008] Figure 3 is a cross-sectional view of the interior portion of the nacelle including the inlet and outlet of the heat exchanger tubes.

[0009] Figure 4 is another exemplary nacelle of a gas turbine engine having heat exchanger ducts extending to a lip. DETAILED DESCRIPTION

[0010] Reference will now be made in detail to the present embodiments of the present disclosure, one or more examples of which are shown in the accompanying drawings. The detailed description uses numerical and letter designations to refer to features in the drawings. The same or similar designations in the drawings and description have been used to refer to the same or similar parts of the present disclosure.

[0011] The term "exemplary" as used herein means "serving as an example, instance, or illustration." Any implementation described herein as "exemplary" is not necessarily to be construed as preferred or better than other implementations. In addition, all embodiments described herein should be considered exemplary unless explicitly stated otherwise.

[0012] The singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise.

[0013] The terms "front" and "rear" refer to relative positions within a gas turbine engine or vehicle and refer to the normal operating attitude of the gas turbine engine or vehicle. For example, for a gas turbine engine, front refers to a position closer to the engine inlet, while rear refers to a position closer to the engine nozzle or exhaust.

[0014] The terms "upstream" and "downstream" refer to the relative directions of the fluid flow in the fluid channel. For example, "upstream" refers to the direction from which the fluid flows, and "downstream" refers to the direction to which the fluid flows.

[0015] The present disclosure is generally directed to improving heat exchanger operation in a gas turbine engine by using fan blades to increase air flow through the heat exchanger and release heated air back to the engine. Certain heat exchanger systems may exhaust heated air outside the engine or be positioned completely downstream of the fan blades, away from ambient air pressure. These systems may lose heated and / or pressurized air due to lack of access to ambient air pressure, which may improve efficient operation of the engine and / or reduce air flow.

[0016] To improve the operation of the heat exchanger system, the inlet of the heat exchanger duct is set behind the fan blades in order to obtain the benefit of the pressure increase caused by the rotation of the fan blades. The air then flows in the opposite direction to the air flow in the engine and flows through the heat exchanger. When heated by the heat exchanger, the heated air passes through the outlet set in front of the fan blades. By setting the outlet in front of the fan blades, the heated air is discharged to a location with ambient air pressure, which provides a pressure difference to make the air flow through the heat exchanger. The outlet is set in the fan duct so that the heated air returns to the fan blades, thereby keeping the heated air within the engine and improving engine efficiency.

[0017] Referring now to the drawings, wherein like numerals represent like elements throughout the several views, Figure 1An exemplary aircraft turbofan gas turbine engine 10, referred to herein as engine 10, is shown including a fan 12, a nacelle 14 extending about the fan, and a turbine 16, all of which surround a central axis 18. The engine 10 defines an axial direction A along the central axis 18, a radial direction R radially away from the central axis 18, and a circumferential direction C about the central axis 18.

[0018] The turbine 16 defines a working gas flow path extending from a turbine inlet 20 to a turbine exhaust 22, and includes a compressor section 24, a combustion section 26, and a turbine section 28 arranged in a series flow order. The compressor section 24, the combustion section 26, and the turbine section 28 partially define the working gas flow path and generate a rotational torque provided to the fan 12 through the output shaft during operation of the engine 10. The turbine 16 also includes an outer casing 30 that at least partially surrounds the compressor section 24, the combustion section 26, and the turbine section 28.

[0019] Notably, for the illustrated embodiment, nacelle 14 also extends around at least a portion of turbine 16, and more specifically, around at least a portion of outer casing 30 of turbine 16. Turbine 16 is supported relative to nacelle 14 by a plurality of exit guide vanes 32.

[0020] The fan 12 includes at least one row of fan blades 34 extending radially outward from a rotor disk 36. The fan blades 34 are at least partially positioned within the nacelle 14 and the engine 10, which is suitably designed to be mounted to a wing or fuselage of an aircraft. The nacelle 14 defines a fan duct 38, an engine inlet 40, and a fan duct exhaust 42, wherein the fan duct 38 extends from the engine inlet 40 to the fan duct exhaust 42. In this manner, it should be understood that the fan blades 34 are disposed in the fan duct 38, and that the fan duct 38 extends over the turbine 16 (and is partially defined between the outer casing of the turbine 16 and the nacelle 14).

[0021] refer to Figure 2 , the nacelle 14 includes an inner portion 44 and an outer surface 46 along a radial direction R. The inner portion 44 of the nacelle 14 faces the interior of the gas turbine engine 10, in particular the fan duct 38. The outer surface 46 of the nacelle 14 surrounds the turbine 16, and the inner portion 44 is the portion of the nacelle 14 located radially inward of the outer surface 46. In the illustrated embodiment, the engine inlet 40 defined by the nacelle 14 includes the forwardmost portion of the inner portion 44 of the nacelle 14, i.e., the portion of the nacelle 14 through which ambient air from outside the engine 10 enters the fan duct 38.

[0022] A heat exchanger duct 48 is defined in the interior portion 44. The heat exchanger duct 48 is a passage for air from the fan duct 38 to flow to the heat exchanger 50, which will be described in further detail below. The heat exchanger duct 48 defines an inlet 52 and an outlet 54. The inlet 52 and the outlet 54 are in fluid communication with the fan duct 38, and more specifically, are in direct fluid communication with the fan duct 38 (i.e., receiving air flow directly from the fan duct 38 and providing air flow directly to the fan duct 38). This configuration allows an air flow 56 in the fan duct 38 of the gas turbine engine 10 to enter the inlet 52, and allows a heated air flow 58 to exit the outlet 54 back into the fan duct 38 of the gas turbine engine 10. Specifically, the outlet 54 discharges the air flow 58 directly to the fan duct 38, thereby preventing air flowing through the heat exchanger duct 48 from flowing outside the gas turbine engine 10 and away from the gas turbine engine 10 (at least without first flowing out through the fan duct exhaust port 42 (see Figure 1 )).

[0023] The inlet 52 is disposed rearward of the outlet 54 along the central axis 18 of the nacelle 14. The inlet 52 receives the air flow 58 pressurized by the fan 12, while the outlet 54 releases the air flow 58 upstream of the fan 12. The outlet 54 is located in the nacelle 14 so that the air flow 58 is discharged to the ambient air flow 60 in the fan duct 38, i.e., air at ambient air pressure. As will be understood, the term "ambient air pressure" or "ambient pressure" refers to the pressure at a location consistent with air that has not passed through a compression rotor blade stage of the engine 10 (e.g., the fan 12, the compressor of the turbine 16, etc.) (e.g., the air pressure at that location).

[0024] In the exemplary embodiment shown, air flow through heat exchanger tube 48 is caused by dynamic head pressure, i.e., the difference between the total pressure at inlet 52 and the static pressure at outlet 54. Inlet 52 and outlet 54 are arranged so that the increased pressure at inlet 52 and the ambient pressure at outlet 54 provide the dynamic head pressure to drive air through heat exchanger tube 48.

[0025] The inlet 52 and the outlet 54 are arranged within the nacelle 14 such that the flow direction of air through the heat exchanger duct 48 is opposite to the flow direction of air through the fan duct 38. More specifically, the air flow through at least a section of the heat exchanger duct 48 includes an axial component in an axial direction from rear to front, while the air flow through the fan duct 38 includes an axial component in an axial direction from front to rear.

[0026] More specifically, the inlet 52 is positioned downstream of the outlet 54 because the air pressure of the air flow 60 passing through the fan duct 38 is higher downstream of the fan blades 34, thereby providing a dynamic pressure head to drive the air flow through the heat exchanger duct 48. The downstream location of the inlet 52 receives the air flow 56 at a higher pressure than the ambient air flow 60 passing through the fan duct 38 at the outlet 54, thereby providing the above-mentioned dynamic pressure head.

[0027] As described above, the nacelle 14 includes a heat exchanger 50 disposed in the heat exchanger duct 48 between the inlet 52 and the outlet 54. The heat exchanger 50 is configured to use air flowing from the inlet 52 to the outlet 54 to cool another fluid, such as oil, flowing through the heat exchanger 50. That is, the heat exchanger 50 transfers heat from the oil to the air, thereby heating the air flowing through the heat exchanger 50 and cooling the oil. The heat exchanger 50 may be a conventional heat exchanger, such as a parallel flow heat exchanger, a cross flow heat exchanger, or a counter flow heat exchanger.

[0028] However, it should be understood that in other exemplary embodiments, any other suitable heat exchanger may be used as the heat exchanger 50. For example, in other exemplary embodiments, the heat exchanger 50 may be a surface heat exchanger positioned in the heat exchanger duct 48 (e.g., integrated into the wall of the heat exchanger duct 48), may be an air-to-air heat exchanger (e.g., cooling an air flow provided through the nacelle 14 to one or more components within the nacelle), etc.

[0029] Still refer to Figure 2 , the heated air flow 58 may be used in the gas turbine engine 10 to improve the operation of the engine 10. Specifically, by reintegrating the heated air flow 58 into the fan duct 38 (rather than exhausting the heated air flow 58 outside the nacelle 14), the energy in the heated air flow 58 in the form of heat and higher pressure may be retained in the fan duct 38, thereby allowing the engine 10 to produce thrust more efficiently.

[0030] In addition, in one example, the heated air flow 58 can be provided to a component to heat the component to melt accumulated ice or inhibit ice formation, i.e., to "de-ice" the component. That is, ice formation on a component may reduce the performance of the gas turbine engine 10 by disrupting air flow through the component or inhibiting the startup of the component. The heated air flow 58 can be used to remove accumulated ice and inhibit ice formation. The heated air flow 58 can be provided to a component (not shown) upstream of the outlet 54, or a component downstream of the outlet 54 (e.g., the inner surface of the nacelle 14).

[0031] refer to Figure 3, shows an interior view of the gas turbine engine 10 looking radially outward. The fan blades 34 move in a circumferential direction C, pushing air at least partially in an axial direction A. The ambient air flow 60 shown in dashed lines represents ambient air that has not yet reached the fan blades 34. The fan blades 34 increase the pressure of the ambient air flow 60. The inlet 52 is located downstream of the fan blades 34 and receives at least some of the air flow 56 pushed / pressurized by the fan blades 34. A plurality of outlets 54 are arranged upstream of the fan blades 34 to return the heated air flow 58 to the fan duct 38, which is also shown in dashed lines because the heated air flow 58 returns to a position within the fan duct 38 at ambient air pressure. The outlets 54 are shown to be arranged circumferentially around the interior portion 44 of the nacelle 14 to distribute the heated air flow 58 through the fan duct 38.

[0032] The inlet 52 and the outlet 54 may be "clocked" in the nacelle 14, i.e., disposed at different axial locations around the interior portion 44 of the nacelle 14. The clocked inlet 52 and outlet 54 prevent the heated air flow 58 from exiting the outlet 54 and then returning to the inlet 52, i.e., "air recirculation" into the inlet 52. Preventing air recirculation increases the efficiency of the heat exchanger 50 by directing the cool air flow into the heat exchanger duct 48. That is, the efficiency of the heat exchanger 50 is based at least in part on the relationship between the air entering the heat exchanger 50 and the other fluids (in the heat exchanger 50) passing through the heat exchanger 50. Figure 2-3 When heated air is reintroduced into the heat exchanger 50, the temperature difference is lower and the heat exchanger 50 may only slightly increase the temperature of the air because less heat is transferred from the oil to the air. When cold air is introduced into the heat exchanger 50, the temperature difference is greater and more heat is transferred from the oil to the cold air. Due to the increased efficiency of the heat exchanger 50, a smaller heat exchanger 50 may be used, thereby addressing weight and size limitations of the gas turbine engine 10.

[0033] Furthermore, it should be understood that although Figure 3 In the illustrated embodiment, the nacelle 14 includes a single inlet 52 and multiple outlets 54, but in other embodiments, the nacelle 14 may also include multiple inlets 52, each inlet 52 being clocked relative to each outlet 54 to inhibit recirculation of air into the inlet 52. With this configuration, each inlet 52 may correspond to a dedicated outlet 54, and the heat exchanger duct 48 may include multiple heat exchanger ducts 48 extending between the respective inlet 52 and outlet 54.

[0034] refer to Figure 4 , another exemplary gas turbine engine 70 is shown. Figure 4 The gas turbine engine 70 may be used in the same manner as described above. Figures 1 to 3The depicted exemplary gas turbine engine 10 is configured in a similar manner, and the same or similar numbers may refer to the same or similar parts.

[0035] for Figure 4 In an embodiment of the present invention, a gas turbine engine 70 (also referred to herein as engine 70) includes a nacelle 72 including a lip 74 disposed at a forward end of the nacelle 72. The lip 74 refers to the front 10% of the nacelle 72. As described above, reducing ice formation on components of the engine 70 can improve the operation of the engine 70. When ice accumulates on the lip 74, air flow into the engine 70 may be interrupted and / or reduced. De-icing the lip 74 can improve the air flow into the engine 70, and the heat exchanger conduit 76 can be arranged so that the heat exchanger 50 provides heated air to de-ice the lip 74.

[0036] The lip 74 defines a cavity 78 that is in fluid communication with the heat exchanger tube 76. Figure 4 In the exemplary nacelle 72 of FIG. 5 , the ambient air flow 60 flows over the fan blades 34 and enters the inlet 80 of the heat exchanger duct 76 as the air flow 56, passes through the heat exchanger 50, and reaches the outlet 82 of the heat exchanger duct 76, which is disposed at the lip 74 (e.g., positioned within or open to the lip 74) and faces the cavity 78. The heated air flow 58 from the heat exchanger 50 is discharged through the outlet 82 and enters the cavity 78. The heated air flow 58 in the cavity 78 heats the lip 74, melts any accumulated ice and inhibits further ice formation on the lip 74. Therefore, de-icing the lip 74 using the heated air flow 58 output from the heat exchanger duct 76 can improve the performance of the engine 70.

[0037] The lip 74 can be in fluid communication with the fan duct 84 through a lip opening 86 located inside the nacelle 72. The heated air flow 58 from the outlet 82 flows through the cavity 78 to heat the lip 74, and then the heated air flow 58 flows through the lip opening 86 back to the fan duct 84. Figure 3 As with the outlet 54 shown in FIG. 5 , the lip opening 86 can be clocked relative to the inlet 80 of the heat exchanger duct 76 to inhibit the heated air flow 58 from recirculating from the lip opening 86 to the heat exchanger 50. In addition, not shown in the figure, the lip opening 74 can include a plurality of lip openings 86 arranged circumferentially around the nacelle 72, and each of the plurality of lip openings 86 can be clocked relative to the inlet 80. As an example, the plurality of lip openings 86 can be positioned around the entire circumference of the lip 74 to increase the amount of heated air flow 58 flowing into the fan duct 84. The subject matter of the following clauses provides further aspects:

[0038] A nacelle for a gas turbine engine defining a radial direction, the nacelle comprising: an inner portion along the radial direction, the inner portion defining a heat exchanger duct, the heat exchanger duct defining an inlet and an outlet; and a heat exchanger disposed in the heat exchanger duct between the inlet and the outlet, wherein the inlet is disposed behind the outlet along a central axis of the nacelle.

[0039] A nacelle according to any of the preceding clauses, wherein the inlet and the outlet are arranged at different circumferential positions around the interior portion.

[0040] The nacelle according to any of the preceding clauses, further comprising a lip at a front end of the nacelle, wherein the outlet is provided at the lip.

[0041] The nacelle according to any of the preceding clauses, wherein the outlet is arranged to discharge air from the heat exchanger to a fan duct of the gas turbine engine.

[0042] The nacelle according to any of the preceding clauses, wherein the heat exchanger duct further comprises a plurality of outlets arranged circumferentially around the nacelle.

[0043] A nacelle as claimed in any preceding clause, wherein the outlet is configured to discharge air into an air flow at ambient pressure.

[0044] A nacelle according to any of the preceding clauses, wherein the heat exchanger is configured to heat air flowing from the inlet to the outlet.

[0045] The nacelle according to any of the preceding clauses, wherein the inlet and the outlet are in fluid communication with a fan duct of the gas turbine engine.

[0046] A gas turbine engine defining a radial direction, the gas turbine engine comprising: a nacelle defining a fan duct, the nacelle comprising: an inner portion along the radial direction, the inner portion defining a heat exchanger duct, the heat exchanger duct defining an inlet and an outlet; and a heat exchanger, the heat exchanger being arranged in the heat exchanger duct between the inlet and the outlet; and fan blades, the fan blades being arranged in the fan duct, wherein the inlet is arranged behind the fan blades along the central axis of the nacelle, and the outlet is arranged in front of the fan blades along the central axis of the nacelle.

[0047] A gas turbine engine as claimed in any one of the preceding clauses, wherein the fan blades are configured to increase air pressure in the fan duct to direct air into the inlet.

[0048] A gas turbine engine as claimed in any one of the preceding clauses, wherein the inlet and the outlet are arranged at different circumferential positions around the nacelle.

[0049] The gas turbine engine according to any of the preceding clauses, wherein the nacelle further comprises a lip at a front end of the nacelle, wherein the outlet is provided at the lip and is configured to discharge air into the lip.

[0050] A gas turbine engine according to any one of the preceding clauses, wherein the lip defines a cavity in fluid communication with the heat exchanger duct and the fan duct, and wherein the outlet is arranged to direct the air from the heat exchanger to the cavity.

[0051] A gas turbine engine as claimed in any one of the preceding clauses, wherein the outlet is arranged to discharge air from the heat exchanger to the fan duct.

[0052] A gas turbine engine according to any one of the preceding clauses, wherein the heat exchanger duct further comprises a plurality of outlets arranged circumferentially around the nacelle.

[0053] A gas turbine engine as claimed in any one of the preceding clauses, wherein the inlet and the outlet are in fluid communication with the fan duct.

[0054] A gas turbine engine as claimed in any preceding clause, wherein the outlet is configured to discharge air into an air flow at ambient pressure.

[0055] A gas turbine engine as claimed in any one of the preceding clauses, wherein the heat exchanger is configured to heat air flowing from the inlet to the outlet.

[0056] A gas turbine engine as claimed in any one of the preceding clauses, wherein the outlet is arranged to direct heated air exiting the outlet onto a component to de-ice the component.

[0057] A gas turbine engine according to any one of the preceding clauses, wherein the flow direction of air through the heat exchanger duct is opposite to the flow direction of air through the fan duct.

[0058] This written description uses examples to disclose the disclosure, including the best mode, and also to enable those skilled in the art to practice the disclosure, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the disclosure is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements that do not differ substantially from the literal language of the claims.

Claims

1. A nacelle for a gas turbine engine defining a radial direction, characterized in that The cabin comprises: an inner portion along the radial direction, the inner portion defining a heat exchanger tube, the heat exchanger tube defining an inlet and an outlet; and a heat exchanger disposed in the heat exchanger conduit between the inlet and the outlet, Wherein, the inlet is arranged behind the outlet along the central axis of the cabin.

2. The nacelle according to claim 1, characterized in that in, The inlet and the outlet are disposed at different circumferential positions around the inner portion.

3. The nacelle according to claim 1, characterized in that Further comprising a lip at a front end of the nacelle, wherein the outlet is disposed at the lip.

4. The nacelle according to claim 1, characterized in that in, The outlet is arranged to discharge air from the heat exchanger to a fan duct of the gas turbine engine.

5. The nacelle according to claim 1, characterized in that in, The heat exchanger conduit further includes a plurality of outlets arranged circumferentially around the nacelle.

6. The nacelle according to claim 1, characterized in that in, The outlet is configured to discharge air into an air flow at ambient pressure.

7. The nacelle according to claim 1, characterized in that in, The heat exchanger is configured to heat air flowing from the inlet to the outlet.

8. The nacelle according to claim 1, characterized in that in, The inlet and the outlet are in fluid communication with a fan duct of the gas turbine engine.

9. A gas turbine engine with a defined radial direction, characterized in that: The gas turbine engine comprises: A nacelle defining a fan duct, the nacelle comprising: an inner portion along the radial direction, the inner portion defining a heat exchanger conduit, the heat exchanger conduit defining an inlet and an outlet; and a heat exchanger disposed in the heat exchanger conduit between the inlet and the outlet; and a fan blade, wherein the fan blade is arranged in the fan duct, Wherein, the inlet is arranged behind the fan blades along the central axis of the nacelle, and the outlet is arranged in front of the fan blades along the central axis of the nacelle.

10. The gas turbine engine according to claim 9, characterized in that in, The fan blades are configured to increase air pressure within the fan duct.

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