Air duct sealing ring and gas turbine engine

Abstract

The present invention relates to an air duct sealing ring and a gas turbine engine. Among them, the air duct sealing ring includes a first sealing ring made of an elastic material; a second sealing ring made of a pre-compressed first shape memory alloy material with a first phase transition temperature; a third sealing ring made of a pre-compressed second shape memory alloy material with a second phase transition temperature; wherein, the first sealing ring, the second sealing ring, and the third sealing ring are distributed radially from outside to inside, and the first phase transition temperature is less than the second phase transition temperature.

Description

Technical Field

[0001] The present invention relates to the field of gas turbine engines, and particularly to an air duct seal ring and a gas turbine engine. Background Art

[0002] For a gas turbine engine, such as an aeroengine, its normal operation is inseparable from the complex air flow path of the air system to achieve functions such as supplying air to and cooling the turbine air-cooled blades, temperature control of high-temperature components, seal of the fulcrum, and seal of the rim. Among the various components that make up the air flow path of the air system, the air duct is an important and indispensable part. The air duct can guide and supply the relatively low-temperature mainstream air flow led out from the root of the intermediate stage of the high-pressure compressor of the engine to the high-pressure turbine for blade cooling, sealing, etc. In addition to realizing the air extraction function, the air duct also needs to ensure that its front end face has good sealing function to ensure that the air flow does not leak during the operation of the engine. Summary of the Invention

[0003] An object of the present invention is to provide an air duct seal ring.

[0004] An object of the present invention is to provide a gas turbine engine.

[0005] An air duct seal ring according to an aspect of the present invention includes a first seal ring made of an elastic material; a second seal ring made of a pre-compressed first shape memory alloy material with a first phase transition temperature; a third seal ring made of a pre-compressed second shape memory alloy material with a second phase transition temperature; wherein, the first seal ring, the second seal ring, and the third seal ring are distributed radially from outside to inside, and the first phase transition temperature is less than the second phase transition temperature.

[0006] In one or more embodiments of the seal ring, the first seal ring, the second seal ring, and the third seal ring are nested and connected radially.

[0007] In one or more embodiments of the seal ring, the structure of the radial nested connection includes that one of the second seal ring and the third seal ring has a first connection groove, and the other has a first connection protrusion. The first connection groove and the first connection protrusion form a first nested connection structure, and the height of the first nested connection structure is greater than the dimensional deformation amount of the phase change of the second seal ring and the third seal ring. The dimensional deformation amount of the phase change of the second seal ring is less than the dimensional deformation amount of the phase change of the third seal ring.

[0008] In one or more embodiments of the seal ring member, in the radially nested connection structure, one of the first seal ring and the second seal ring has a second connection groove, and the other has a second connection protrusion. The second connection groove and the second connection protrusion form a second nested connection structure, and the height of the second nested connection structure is greater than the dimensional deformation amount of the phase change of the second seal ring.

[0009] In one or more embodiments of the seal ring member, the circumferential positions of the first connection groove or the first connection protrusion of the second seal ring are offset from those of the second connection protrusion or the second connection groove of the second seal ring.

[0010] In one or more embodiments of the seal ring member, the seal ring member has a plurality of first nested connection structures evenly distributed in the circumferential direction and a plurality of second nested connection structures evenly distributed in the circumferential direction. The first nested connection structures and the second nested connection structures are offset in the circumferential direction.

[0011] In one or more embodiments of the seal ring member, the first seal ring, the second seal ring, and the third seal ring are all segmented ring bodies. The circumferential ends of each segment of the ring body are stepped cuts, and stepped notches are formed between adjacent ring bodies.

[0012] In one or more embodiments of the seal ring member, the first seal ring has one of the stepped notches, and the second seal ring and the third seal ring have a plurality of the stepped notches evenly distributed in the circumferential direction.

[0013] A gas turbine engine according to one aspect of the present invention includes a compressor, an air duct, and the above-described seal ring member. The seal ring member is located in the radial space between the air duct and the compressor shaft of the compressor.

[0014] In one or more embodiments of the gas turbine engine, the gas turbine engine has a first state, a second state, and a third state: in the first state, the temperature of the air duct sealing area is less than the first phase change temperature, and there is a clearance fit between the seal ring member and the compressor shaft; in the second state, the temperature of the air duct sealing area is above the first phase change temperature and less than the second phase change temperature, and there is a first interference fit between the seal ring member and the compressor shaft, and the corresponding interference amount is the first interference amount; in the third state, the temperature of the air duct sealing area is above the second phase change temperature, and there is a second interference fit between the seal member and the compressor shaft, and the corresponding interference amount is the second interference amount, where the second interference amount is greater than the first interference amount.

[0015] In one or more embodiments of the gas turbine engine, the sealing area of the air duct includes a sealing groove for installing and accommodating the sealing ring; there is no assembly guiding angle upstream of the sealing groove.

[0016] The advantageous effects of the present invention include but are not limited to that by adopting a sealing structure with multiple sealing rings arranged in multiple radial circles and using a shape memory alloy ring, the sealing ring has a clearance fit with the compressor shaft in the assembled state and an interference fit during operation, so that the sealing structure is convenient for assembly and disassembly, avoiding hard-to-hard friction and extending the service life of parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and other features, properties and advantages of the present invention will become more apparent through the following description in conjunction with the drawings and embodiments. It should be noted that the drawings are only examples and are not drawn under the condition of equal scale, and should not be used to limit the actual protection scope required by the present invention, where:

[0018] Figure 1 is a schematic structural diagram of a gas turbine engine of an embodiment.

[0019] Figure 2 is a schematic structural diagram of a perspective view of an air duct sealing ring of an embodiment.

[0020] Figure 3 is a schematic structural diagram of another perspective view of an air duct sealing ring of an embodiment.

[0021] Figure 4 is a schematic structural diagram of the first sealing ring of an air duct sealing ring of an embodiment.

[0022] Figure 5 is a schematic structural diagram of the second sealing ring of an air duct sealing ring of an embodiment.

[0023] Figure 6 is a schematic structural diagram of the third sealing ring of an air duct sealing ring of an embodiment.

[0024] Figure 7 is a schematic structural diagram of a comparative scheme.

[0025] Partial reference numerals:

[0026] 10 - Air duct sealing ring

[0027] 1 - First sealing ring

[0028] 2 - Second sealing ring

[0029] 3 - Third sealing ring

[0030] 41 - First connecting groove

[0031] 42 - Second connecting groove

[0032] 51 - First connecting protrusion

[0033] 52 - Second connecting protrusion

[0034] 61 - First nested connecting structure

[0035] 62 - Second nested connecting structure

[0036] 7 - Stepped notch

[0037] 70 - Stepped gap

[0038] 100 - Gas turbine engine

[0039] 101 - Fan

[0040] 102 - Boost stage

[0041] 103 - High-pressure compressor

[0042] 104 - Combustion chamber

[0043] 105 - High-pressure turbine

[0044] 106 - Low-pressure turbine

[0045] 107 - Intermediate casing

[0046] 108 - Inter-stage casing

[0047] 109 - Air duct

[0048] 110 - Packing ring

[0049] 120 - Sealing groove

[0050] 130 - Assembly guiding angle structure Detailed implementation manners

[0051] The following discloses various different implementation manners or embodiments for implementing the described subject technical solutions. To simplify the disclosure content, specific examples of each component and arrangement are described below. Of course, these are only examples and are not intended to limit the protection scope of the present invention.

[0052] Additionally, the use of "an embodiment", "one embodiment", and / or "some embodiments" means a certain feature, structure, or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that the "one embodiment" or "an embodiment" or "one or more embodiments" mentioned twice or more at different positions in this specification do not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of the present application can be appropriately combined.

[0053] As Figure 1 shown, taking a two-spool aero gas turbine engine as an example, in one embodiment, the gas turbine engine 100 includes a fan 101. After the air flow enters from the fan 101, a part of it passes through the booster stage 102 and the high-pressure compressor 103, and then enters the combustion chamber 104 to carry out a combustion reaction with fuel, and outputs high-temperature gas to the high-pressure turbine 105 and the low-pressure turbine 106. There is an intermediate casing 107 between the booster stage 102 and the high-pressure compressor 103, and an interstage casing 108 between the high-pressure turbine 105 and the low-pressure turbine 106. The air duct 109 is located radially inside the compressor shaft of the high-pressure compressor 103, and the seal ring 1 is located in the radial space between the air duct 109 and the compressor shaft of the high-pressure compressor 103 to seal the air duct. It can be understood that the gas turbine engine is not limited to being an aero engine, and for example, it can also be a marine gas turbine engine.

[0054] As Figures 2 to 6As shown, in some embodiments, the air duct sealing ring member 10 includes a first sealing ring 1, a second sealing ring 2, and a third sealing ring 3. The first sealing ring 1, the second sealing ring 2, and the third sealing ring 3 are distributed radially from outside to inside. The material of the first sealing ring 1 is an elastic material. Since the temperature of the high-pressure compressor where the air duct sealing ring member 10 is located may be relatively high, it is generally a conventional metal material, selected according to the specific operating temperature, but not limited thereto. For example, it can also be a non-metallic elastic material with good high-temperature resistance, as long as it meets the elastic and durability requirements at the operating temperature and can withstand multiple expansion-recovery cycles. The materials of the second sealing ring 2 and the third sealing ring 3 are both shape memory alloys (SMA, hereinafter referred to as memory alloy). Memory alloy (SMA) is a type of alloy material that can "remember" its initial shape. Since it has both sensor and drive functions, it is an intelligent material. SMA has two special macroscopic mechanical properties: shape memory effect and superelasticity. Among them, the shape memory effect means that when SMA is loaded and unloaded at an environmental temperature lower than its phase transition temperature, there is a residual strain after unloading. At this time, heating it above the phase transition temperature can make the residual strain disappear and return to the state before loading. For example, a spring made of SMA to carry heavy objects will repeatedly lift and lower the heavy object by repeatedly heating and cooling the spring. The second sealing ring 2 and the third sealing ring 3 are made of pre-compressed shape memory alloy materials. They are loaded and formed at a temperature lower than the phase transition temperature, and there is a residual strain after unloading. The second sealing ring 2 and the third sealing ring 3 are in a compressed state during assembly and can automatically deform and recover after the temperature is higher than the phase transition point. Driven by the shape memory effect, the first sealing ring 1 is opened, and when the temperature is lower than the phase transition point, it deforms again. Under the elastic action of the first sealing ring 1 itself, the overall sealing ring member composed of the three sealing rings is compressed again.

[0055] Among them, the phase transition temperatures of the memory alloy materials of the second sealing ring 2 and the third sealing ring 3 are different, that is, the material of the second sealing ring 2 is the pre-compressed first memory alloy material, and the phase transition temperature is the first phase transition temperature T1; the material of the third sealing ring 3 is the pre-compressed second memory alloy material, and the phase transition temperature is the second phase transition temperature T2, and T1 is less than T2. The deformation amount of the second sealing ring 2 after reaching T1 is generally less than the deformation amount of the third sealing ring 3 after reaching T2. The specific ranges of T1 and T2 are generally determined according to the temperature at the air duct sealing location. The relationship between the first phase transition temperature T1, the second phase transition temperature T2, the atmospheric temperature T0, and the temperatures T1* and T2* at the air duct sealing location under different operating states of the engine is: atmospheric temperature T0 < first phase transition temperature T1 < temperature T1* at the sealing location under medium and small operating conditions of the engine < second phase transition temperature T2 < temperature T2* at the sealing location under large operating conditions of the engine.

[0056] The beneficial effects obtained in this way are that the sealing ring is in clearance fit with the compressor shaft in the assembled state and interference fit during operation. Thus, the sealing structure is easy to assemble and disassemble, avoiding hard-on-hard friction and extending the service life of the parts. Specifically, during engine shutdown, the temperature at the air duct sealing location is the atmospheric temperature T0. At this time, the shape memory alloys of the second sealing ring 2 and the third sealing ring 3 have not undergone phase transformation. At this time, the outer diameter d of the first sealing ring 1 is relatively small, and there is a clearance fit with the compressor shaft. During the operation of the engine under medium and small operating conditions, the sealing temperature T1* is between the first phase transformation temperature T1 and the second phase transformation temperature T2. At this time, only the shape memory alloy of the second sealing ring 2 located in the middle layer undergoes phase transformation. Under the action of the deformation recovery ability, the diameter of the second sealing ring 2 increases, driving the outer diameter of the first sealing ring 1 to increase from d to d1, and the fit with the compressor shaft changes from clearance fit to small interference fit, with the interference amount being the first interference amount, ensuring that the air duct sealing ring realizes the sealing function under medium and small operating conditions of the engine. During the operation of the engine under large operating conditions, the high-state sealing temperature T2* is higher than the first phase transformation temperature T1 and the second phase transformation temperature T2. At this time, the shape memory alloys of the second sealing ring 2 in the middle layer and the third sealing ring 3 in the inner layer have both undergone phase transformation. Under the action of the deformation recovery ability, the diameters of the third sealing ring 3 and the second sealing ring 2 both increase, driving the outer diameter of the first sealing ring 1 made of conventional metallic material in the outer layer to increase slightly again, from d1 to d2. The fit between the sealing ring A and the compressor shaft changes from small interference fit to large interference fit, with the interference amount being the second interference amount, that is, the second interference amount is greater than the first interference amount. This ensures that the air duct sealing ring realizes the sealing function under large operating conditions of the engine, thus meeting the more stringent requirements for sealing during large operating conditions of the engine and avoiding the decline in engine performance and the increase in fuel consumption rate caused by leakage.

[0057] In addition, the inventor found that during engine operation, there may be vibrations that cause rubbing of the sealing structure, and factors such as the relatively high temperature at the front end of the air duct and the harsh environment. If the sealing structure is set to be in large interference fit during the operation of the engine under medium and small operating conditions, after multiple working cycles of temperature increase and decrease, the first sealing ring 1 made of conventional metallic material in the outer layer is prone to fatigue damage, resulting in a decrease in service life and even causing faults such as cracks and failures. Therefore, by setting the second sealing ring 2 and the third sealing ring 3 with different phase transformation temperatures, the fatigue life of the sealing ring member 10 can be long and the reliability can be high.

[0058] Compare Figure 7 The comparative scheme shown can more clearly understand the beneficial effects of the above embodiments. In Figure 7In the comparative solution shown, a packing ring 110 is used for sealing the front end of the air duct 109. Structures such as an open C-shaped snap ring / circlip are adopted. During assembly, it is manually pressed into the sealing groove 120 by an assembly technician. After the external force is removed, the packing ring 110 will naturally expand outwards. During assembly, a special assembly guiding angle structure 130 machined on the compressor shaft that cooperates with it is required to guide the interference-fitted packing ring 110 to be assembled in place. After being assembled in place, a radial interference is formed between the packing ring 110 and the compressor shaft on the outer side to achieve a sealing function. During actual assembly, the front end of the engine is vertically downward. The tooling first lowers the air duct to the front end of the compressor, and then pulls up the air duct to assemble the air duct in place through the guiding angle structure 130. The comparative solution has difficulties in engine assembly and requires the design of a special guiding angle structure; the sealing part of the air duct is affected by factors such as the relatively high temperature of the intermediate-stage air extraction of the compressor and vibration friction during operation, and it is an interference fit, so it will be more difficult to disassemble, which will cause inevitable hard contact friction between the snap ring / circlip structure and the compressor shaft, further causing negative impacts such as wear of parts such as the snap ring / circlip, air duct, and compressor shaft and shortening of service life. Compared with Figure 7 the comparative solution shown, the sealing ring member 1 of the above embodiments can also be arranged in the sealing groove 120, but it is not necessary to have an assembly guiding angle 130 upstream of the sealing groove 120. In this way, the structural design of the engine can be simplified, and it is a clearance fit during assembly and disassembly, which is convenient for assembly and disassembly, avoids hard contact friction, and prolongs the service life of parts.

[0059] Continuing to refer to Figures 2 to 6 , in some embodiments, the first sealing ring 1, the second sealing ring 2, and the third sealing ring 3 are nested and connected radially. The specific radially nested connection structure can be that one of the second sealing ring 2 and the third sealing ring 3 has a first connection groove 41, and the other has a first connection protrusion 51, as Figure 5 and Figure 6As shown, the second sealing ring may have a first connecting groove 41, and the third sealing ring 3 may have a first connecting protrusion 51. The first connecting groove 41 and the first connecting protrusion 51 form a first nested connection structure 61. The height H of the first nested connection structure 61 is greater than the dimensional deformation amount of the phase change of the second sealing ring 2 and the third sealing ring 3. The beneficial effect is that the connection of the first nested connection structure 61 can be made firm. The principle is that when the first phase change temperature T1 < the temperature T1* at the sealing position under medium and small engine operating conditions < the second phase change temperature T2, at this time, the second sealing ring 2 undergoes deformation recovery, while the third sealing ring 3 is still the size at the time of installation. Therefore, the setting of the height of the first nested connection structure 61 can prevent the second sealing ring 2 and the third sealing ring 3 from detaching during the operation of the engine. Similarly, when the temperature drops from the temperature T2* at the sealing position under large engine operating conditions to the temperature T1* at the sealing position under medium and small engine operating conditions, at this time, the deformation amount of the phase change of the third sealing ring 3 has been eliminated and it returns to the initial installation state, while the second sealing ring 2 still has the deformation amount of the phase change. Therefore, the setting of the height of the first nested connection structure 61 can prevent the second sealing ring 2 and the third sealing ring 3 from detaching during the operation of the engine. Similarly, in one or more embodiments, refer to Figure 4 and Figure 5 , the radially nested connection structure further includes that one of the first sealing ring 1 and the second sealing ring 2 has a second connecting groove 42, and the other has a second connecting protrusion 52. The second connecting groove 42 and the second connecting protrusion 52 form a second nested connection structure 62. The height of the second nested connection structure 62 is greater than the dimensional deformation amount of the phase change of the second sealing ring 2. Although the first sealing ring 1 itself has elasticity and the possibility of loosening between the first sealing ring 1 and the second sealing ring 2 is lower than that between the second sealing ring 2 and the third sealing ring 3, such a set height can make the second nested connection structure 62 more reliable.

[0060] Refer to Figure 5 , in an embodiment, the first connecting groove 41 of the second sealing ring 2 and the second connecting protrusion 52 of the second sealing ring 2 are staggered in the circumferential direction. In this way, stress concentration can be reduced and the fatigue life of the second sealing ring 2 can be improved. Similarly, if the second sealing ring 2 has a first connecting protrusion and a second connecting groove, the two are also staggered in the circumferential direction. Further, refer to Figure 2 and Figure 3 , a plurality of first nested connection structures 61 and a plurality of second nested connection structures 62 are evenly distributed in the circumferential direction of the sealing ring member 10, and the plurality of first nested connection structures 61 and the plurality of second nested connection structures 62 are staggered in the circumferential direction. Such an alternating arrangement makes the radial nested connection between the sealing rings more reliable and firm.

[0061] Continue to refer to Figures 2 to 6As shown, in some embodiments, the first seal ring 1, the second seal ring 2, and the third seal ring 3 are all segmented ring bodies. The circumferential two ends of each ring body are stepped notches 7, and stepped gaps 70 are formed between adjacent rings. As Figures 4 to 6 shown, the first seal ring 1 has one stepped gap 70, and the second seal ring 2 and the third seal ring 3 have four stepped gaps 70 evenly distributed in the circumferential direction. The beneficial effect of using the stepped gap is that it is easy to assemble and disassemble, and it is easy to open and compress during the operation of the engine, reducing the air leakage phenomenon.

[0062] As can be known from the above, the beneficial effects of using the air duct seal ring and the gas turbine engine introduced in the above embodiments include but are not limited to, by adopting a seal structure with multiple seal rings arranged in multiple radial circles and using a shape memory alloy ring, the seal ring is in clearance fit with the compressor shaft in the assembled state and in interference fit during operation, so that the seal structure is convenient for assembly and disassembly, avoiding hard-on-hard friction and prolonging the service life of parts.

[0063] Although the present invention is disclosed as above with the above embodiments, it is not used to limit the present invention. Any person skilled in the art can make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, any modification, equivalent change, and modification made to the above embodiments based on the technical essence of the present invention without departing from the technical solution of the present invention shall fall within the protection scope defined by the claims of the present invention.

Claims

1. An air duct sealing ring, characterized in that, Comprising: A first seal ring, made of an elastic material; A second seal ring, made of a pre-compressed first shape memory alloy material with a first phase transition temperature; A third seal ring, made of a pre-compressed second shape memory alloy material with a second phase transition temperature; Wherein, the first seal ring, the second seal ring, and the third seal ring are distributed radially from outside to inside, and the first phase transition temperature is less than the second phase transition temperature; The first seal ring, the second seal ring, and the third seal ring are nested and connected radially; The structure of the radial nested connection includes that one of the second seal ring and the third seal ring has a first connection groove, and the other has a first connection protrusion. The first connection groove and the first connection protrusion form a first nested connection structure, and the height of this first nested connection structure is greater than the dimensional deformation amount of the phase change of the second seal ring and the third seal ring. The dimensional deformation amount of the phase change of the second seal ring is less than the dimensional deformation amount of the phase change of the third seal ring.

2. The seal ring member according to claim 1, wherein, The structure of the radial nested connection includes that one of the first seal ring and the second seal ring has a second connection groove, and the other has a second connection protrusion. The second connection groove and the second connection protrusion form a second nested connection structure, and the height of this second nested connection structure is greater than the dimensional deformation amount of the phase change of the second seal ring.

3. The sealing ring part according to claim 2, wherein The first connection groove or the first connection protrusion of the second seal ring is circumferentially offset from the second connection protrusion or the second connection groove of the second seal ring.

4. The sealing ring part according to claim 3, characterized in that, The seal ring member has a plurality of first nested connection structures evenly distributed circumferentially, and a plurality of second nested connection structures evenly distributed circumferentially. The first nested connection structure and the second nested connection structure are circumferentially offset.

5. The seal ring member according to claim 1, wherein, The first seal ring, the second seal ring, and the third seal ring are all segmented ring bodies. The circumferential ends of each segment of the ring body are stepped cutouts, and stepped notches are formed between adjacent ring bodies.

6. The seal ring according to claim 5, characterized in that The first seal ring has one of the stepped notches, and the second seal ring and the third seal ring have a plurality of the stepped notches evenly distributed circumferentially.

7. A gas turbine engine, characterized in that, Comprising a compressor, an air duct, and a seal ring member as described in any one of claims 1-6. The seal ring member is located in the radial space between the air duct and the compressor shaft of the compressor.

8. The gas turbine engine according to claim 7, characterized in that, The gas turbine engine has a first state, a second state, and a third state: In the first state, the temperature of the air duct sealing area is less than the first phase transition temperature, and there is a clearance fit between the seal ring member and the compressor shaft; In the second state, the temperature of the air duct sealing area is above the first phase transition temperature and less than the second phase transition temperature. The seal ring member and the compressor shaft are in a first interference fit, and the corresponding interference amount is the first interference amount; In the third state, the temperature of the air duct sealing area is above the second phase transition temperature. The seal ring member and the compressor shaft are in a second interference fit, and the corresponding interference amount is the second interference amount. Wherein, the second interference amount is greater than the first interference amount.

9. The gas turbine engine according to claim 7, wherein The sealing area of the air duct includes a sealing groove for installing and accommodating the sealing ring; there is no assembly guiding angle upstream of the sealing groove.

Images