CN114962059A - Exhaust nozzle, aircraft engine and aircraft - Google Patents

Abstract

The invention discloses a tail nozzle, an aero-engine and an aircraft. The tail nozzle includes a plurality of segmented parts, and the segmented parts surround the exhaust port of the tail nozzle. The tail nozzle also includes a deformed inner ring made of shape memory alloy, wherein the There are slits between the segmented parts, the deformed inner ring is arranged on the inner side of the segmented parts, and at least a part of the deformed inner ring coincides with the slits in the axial direction, and is driven by the temperature deformation state The segment moves and changes the spacing of the slits, thereby changing the size of the exhaust port of the tail nozzle. The shape memory alloy is used as the actuating mechanism to change the nozzle area of the control tail nozzle at different temperatures, so as to effectively avoid the problem of noise without adding excessive weight and complicated mechanism.

Description

Nozzle, aero engine and aircraft

technical field

The invention relates to a tail nozzle, an aero-engine and an aircraft.

Background technique

The tail nozzle of the aero-engine has different working states when it works. By changing the size of the exit of the tail nozzle, the working state of the engine can be changed, so that the engine can obtain good performance in various working conditions. However, the tail nozzle with adjustable nozzle is usually a mechanical structure, which is complicated in structure and heavy in weight, and the mechanical transmission components are unreliable under high temperature. Therefore, civil turbofan engines use non-adjustable convergent tail nozzles.

At present, high bypass ratio turbofan engines usually use non-adjustable convergent tail nozzles, also known as subsonic nozzles with fixed nozzles, including zigzag tail nozzles with noise reduction function, which are the simplest in structure and lightest in weight. , CFM56, PW4000, RB211, GE90 and almost all civil turbofan engines use this tail nozzle. Although when the available drop pressure ratio of the nozzle is greater than the critical drop pressure ratio (1.85), the gas cannot be fully expanded in the converging tail nozzle, but when the flight speed is not large (Ma≤1.5), the gas will not fully expand due to incomplete expansion. The loss of energy is small, so it is appropriate to use this simple convergent tail nozzle.

However, in addition to the energy loss caused by incomplete expansion of the gas (leading to the reduction of engine efficiency), with the improvement of the environmental indicators of aero-engines, the noise problem caused by the different jet speeds of the engine at different working state points has become increasingly prominent. , Although the zigzag noise reduction tail nozzle is designed accordingly, the noise problem still exists at the non-working point of the engine, such as the maximum climb.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to provide a tail nozzle, an aero-engine and an aircraft in order to overcome the defect of high noise in different working states of the aero-engine in the prior art while ensuring a simple structure and light weight.

The present invention solves the above-mentioned technical problems through the following technical solutions:

A tail nozzle is used for an aero-engine, and includes a plurality of segmented parts, and the segmented parts are arranged to form an exhaust port of the tail nozzle. A deformed inner ring made of an alloy, wherein a slit is formed between the segmented parts, the deformed inner ring is arranged on the inner side of the segmented part, and at least a part of the deformed inner ring is in the axial direction with the The slits are overlapped, and in the state of temperature deformation, the segmented portion is driven to move and the distance between the slits is changed, thereby changing the size of the exhaust port of the tail nozzle.

Using shape memory alloy as the actuating mechanism to control the nozzle area of the tail nozzle can effectively avoid the problem of noise without adding excessive weight and complicated mechanism. The deformation inner ring can match the corresponding working state by setting the phase transition temperature. When the exhaust gas of the tail nozzle reaches the phase transition temperature, deformation occurs, so that the exhaust port of the tail nozzle reaches the preset size and effectively reduces noise.

At the same time, the slit realizes a larger change in the size of the exhaust port. The deformed inner ring located on the inner side of the split part blocks the inside of the slit on the one hand, and can still be sealed on the inside when the slit is opened. , to block gas leakage from the slit. On the other hand, the deformed inner ring acts on the inner side of the segmented part, and can expand evenly from the inner side. The bulging phenomenon is avoided when the deformed inner ring acts on the outer side of the segmented part, and the movement of the deformed inner ring and the segmented part is prevented from being disconnected.

Preferably, the shape of the slit is one or a combination of a straight line, an S-shaped slit, and a zigzag shape.

Preferably, the shape of the segmented portion is one or a combination of a zigzag shape, a circular arc shape, and a trapezoid shape.

Preferably, the deformed inner ring is a circumferentially continuous structure, and the deformed inner ring is completely shielded from the inner side of each of the slits in the circumferential direction.

Preferably, the shape of the deformed inner ring is one or a combination of a cylindrical structure with uniform wall thickness, a corrugated plate, and a spring.

Preferably, a fitting groove is formed on the inner side of each of the segmented parts, each of the fitting grooves forms a fitting ring along the circumferential direction, and the deformed inner ring has a cylindrical shape and is embedded in the fitting ring. inside the ring.

Preferably, the circumferential dimensions of the deformed inner ring are different at a plurality of different temperatures, and the segmented parts are stretched to different positions at different temperatures, so that the exhaust port of the tail nozzle is changed. into several different sizes.

Preferably, the deformed inner ring can be deformed with different circumferential dimensions at a plurality of different temperatures by a combination of materials passing through different phase transition points.

Preferably, the deformation inner ring is provided with at least two deformation segments, and at least two of the deformation segments have different phase transition temperatures. Therefore, for the three states of the engine at idle, climbing, and cruising, the tail nozzle has different exhaust temperatures in these three states, and the expansion or closing of the tail nozzle is realized by deforming the inner ring to shrink or expand at different temperatures.

Preferably, the deformed segments are distributed along the circumferential direction of the deformed inner ring, wherein the deformed segments with the same phase transition temperature are uniformly distributed at various positions of the deformed inner ring along the circumferential direction.

Preferably, the deformed inner ring is made by additive manufacturing.

Preferably, the deformation inner ring is provided with at least two deformation segments with different phase transition temperatures, and the deformation segments with different phase transition temperatures are produced by applying different additive manufacturing process parameters to the same shape memory alloy. processed.

Preferably, the additive manufacturing process parameters are one or more parameters of laser power, scanning rate and scanning distance, and/or the shape memory alloy is a nickel-titanium alloy.

Preferably, the deformation segments with different phase transition temperatures are sequentially scanned by laser along the circumferential direction, and the material crystal phases between the adjacent deformation segments with different phase transition temperatures transition smoothly. Since it is made of the same shape memory alloy, the deformation segments of the deformed inner ring are still integrated, and through laser scanning, the adjacent deformation segments are also heated when scanning the deformation segments, so that the crystal phase between the deformation segments is Changes slowly, therefore, no stress concentration occurs at the junction between the deformed segments, ensuring the strength of the deformed inner ring during repeated deformation.

An aero-engine is characterized in that the aero-engine includes the tail nozzle, wherein the tail nozzle is the inner nozzle and/or the outer nozzle of the aero-engine.

An aircraft is characterized in that the aircraft includes the aero-engine.

The positive improvement effect of the present invention is: using shape memory alloy as the actuating mechanism to change the nozzle area of the control tail nozzle at different temperatures, so as to effectively avoid the problem of noise without adding excessive weight and complicated mechanism.

Description of drawings

FIG. 1 is a schematic structural diagram of an aero-engine according to a preferred embodiment of the present invention.

FIG. 2 is a schematic structural diagram of a tail nozzle according to a preferred embodiment of the present invention.

FIG. 3 is a schematic structural diagram of a fragmentation part according to a preferred embodiment of the present invention.

FIG. 4 is a schematic diagram of the cross-sectional structure in the initial state along the A-A direction in FIG. 2 .

FIG. 5 is a schematic diagram of a cross-sectional structure in the direction A-A of FIG. 2 in a first working state.

FIG. 6 is a schematic diagram of a cross-sectional structure in the direction A-A of FIG. 2 in a second working state.

FIG. 7 is a schematic diagram of the arrangement of a deformation segment of the deformation inner ring according to the preferred embodiment of the present invention.

FIG. 8 is a schematic diagram of another arrangement of deformation segments of the deformation inner ring according to the preferred embodiment of the present invention.

Detailed ways

The present invention is further described below by way of examples, but the present invention is not limited to the scope of the described examples.

As shown in FIG. 1 , this embodiment discloses an aero-engine, which is mainly used in an aircraft, and the aircraft may include one or more aero-engines of this embodiment. Among them, as shown in FIG. 1 , this embodiment exemplarily shows a specific structure of an aero-engine, including an engine nacelle 1 , an external nozzle 2 , an internal nozzle 3 , an internal channel 4 , and an external channel 5 . Wherein, the tail nozzle 6 of this embodiment can be used for the internal nozzle 3 and/or the external nozzle 2 of the aero-engine. In other structures of aero-engines, the tail nozzle 6 can also be used in the corresponding nozzle structure.

As shown in FIGS. 2 to 3 , the tail nozzle 6 of this embodiment includes a plurality of segmented parts 61, and the segmented parts 61 are formed around the exhaust port of the tail nozzle 6, and the tail nozzle 6 also includes a shape memory A deformed inner ring 62 made of alloy, wherein a slit 63 is provided between the segment parts 61, the deformed inner ring 62 is arranged on the inner side of the segment part 61, and at least a part of the deformed inner ring 62 is in the axial direction with the slit 63 overlap, and in the state of temperature deformation drives the segment 61 to move and change the spacing of the slits 63, thereby changing the size of the exhaust port of the tail nozzle 6.

Using shape memory alloy as the actuating mechanism to control the nozzle area of the tail nozzle 6 can effectively avoid the problem of noise without adding excessive weight and complicated mechanism. The deformation inner ring 62 can be set to match the corresponding working state by setting the phase transition temperature. When the exhaust gas of the tail nozzle 6 reaches the phase transition temperature, deformation occurs, so that the exhaust port of the tail nozzle 6 reaches the preset size, which is effective. Reduce noise.

At the same time, the slit 63 realizes a larger change in the size of the exhaust port. The deformed inner ring 62 located on the inner side of the segment 61 blocks the inside of the slit 63 on the one hand. Sealing can be performed on the inside to block gas leakage from the slit 63 . On the other hand, the deformed inner ring 62 acts on the inner side of the segment portion 61, and can be expanded evenly from the inner side. The bulging phenomenon is avoided when the deformed inner ring 62 acts on the outer side of the segmented portion 61 , and the movement of the deformed inner ring 62 and the segmented portion 61 is prevented from being disconnected.

The shape memory alloy referred to in this embodiment may be a nickel-titanium alloy, and may also include but not limited to a copper-nickel alloy, a copper-aluminum alloy, and a copper-zinc alloy. In other embodiments, other known shape memory alloy materials may also be used. In the description of this embodiment, the axial direction and the circumferential direction refer to the axial direction and the circumferential direction of the tail nozzle 6 respectively.

In this embodiment, the dimensional change of the shape memory alloy can be calculated by numerical simulation method based on the deformation coefficient of the shape memory alloy, but is not limited to. For example, the aerodynamic-noise coupling multi-disciplinary and multi-working condition optimization method can be used to obtain the most optimal conditions for each state based on the relationship between the engine take-off, cruising, and landing noise, aerodynamic performance and the size of the exhaust port 60 according to different working state points. Optimum exhaust port size, so as to determine that the size of the shape memory alloy has changed, so that while the aerodynamic performance is comprehensively improved at different working conditions, the noise level is always maintained within the range of airworthiness requirements, reducing engine take-off, cruise, and landing. The air resistance of the tail nozzle and the aerodynamic interference resistance between the engine and the aircraft in different working conditions.

In a preferred embodiment, the structural design scheme of the tail nozzle 6 is applied to the inner nozzle. Due to the high exhaust gas temperature, thermal insulation measures can be further designed, such as by coating the inner side of the tail nozzle 6 with thermal insulation. Ceramic coating, or by additively manufacturing shape memory alloy powder element control, such as the use of 25% Ni, 25% Pd, 16.6% Ti, 16.7% Hf, 16.6% Zf formula, can transform the phase change. The temperature is increased to 700°C-800°C.

In this embodiment, the shape of the slit 63 is one or a combination of a straight line, an S-shaped slit, and a zigzag shape. The shape of the segmented portion 61 is one or a combination of a zigzag shape, a circular arc shape, and a trapezoid shape. Of course, in other embodiments, the slicing parts and slits of other shapes are also possible.

In a preferred embodiment, the deformed inner ring 62 is a circumferentially continuous structure, and the deformed inner ring 62 is completely shielded from the inner side of each slit 63 in the circumferential direction. As a result, gas leakage from the slit 63 can be prevented in the circumferential direction. At the same time, the continuous structure can also realize the overall deformation and increase the deformation force. In a further preferred embodiment, the shape of the deformed inner ring 62 is one or a combination of a cylindrical structure with a uniform wall thickness, a corrugated plate, and a spring.

As shown in FIG. 3 , in a preferred embodiment, a fitting groove 611 is formed on the inner side of each segment portion 61 , each fitting groove 611 forms a fitting ring along the circumferential direction, and the deformed inner ring 62 is a cylinder shape and is embedded in the fitting ring.

As shown in FIG. 4 , FIG. 5 and FIG. 6 , in a preferred embodiment, the deformed inner ring 62 has different circumferential dimensions at a plurality of different temperatures, and the segmented parts 61 are stretched to different sizes at different temperatures position so that the exhaust port of the tail nozzle 6 is changed to a plurality of different sizes.

In a further preferred embodiment, the deformable inner ring 62 is deformed with different circumferential dimensions at a plurality of different temperatures by combining materials with different phase transition points. In a more preferred embodiment, the deformation inner ring 62 is provided with at least two deformation segments, and the at least two deformation segments have different phase transition temperatures. Therefore, for the three states of the engine at idle, climbing and cruising, the tail nozzle 6 has different exhaust gas temperatures in these three states. closure.

Wherein, in a further preferred embodiment, the deformation segments are distributed along the circumferential direction of the deformed inner ring 62 , wherein the deformation segments with the same phase transition temperature are evenly distributed at various positions of the deformed inner ring 62 along the circumferential direction. As shown in FIG. 7 , the deformed inner ring 62 is provided with two deformed segments a and b, and the two deformed segments a and b are arranged around the deformed inner ring 62 . The deformed inner ring 62 shown in FIG. 7 is provided with three deformation segments a, b and c, and the three deformation segments a, b and c are arranged around the deformed inner ring 62 .

In a further preferred embodiment, the deformed inner ring 62 is made by additive manufacturing. The deformation inner ring 62 is provided with at least two deformation segments with different phase transition temperatures, and the deformation segments with different phase transition temperatures are formed by processing the same shape memory alloy using different additive manufacturing process parameters.

In a preferred embodiment, the additive manufacturing process parameters may be one or more parameters of laser power, scanning rate and scanning spacing, and changing the laser power causes the laser energy density to change, and changing the scanning rate causes the laser energy density to change. As well as the test of different samples formed by changing the laser energy density due to the variable scanning distance, it can be seen that the overall phase transition temperature increases with the increase of the laser energy density used for forming.

Therefore, in a preferred embodiment, different laser energy densities can be obtained by adjusting one or more of the laser power, scanning rate and scanning interval, and each deformation segment in the deformation unit is formed by using different laser energy densities, Each deformation segment can be made to have a different phase transition temperature. Wherein, the laser energy density used corresponding to each target phase transition temperature can be determined by means of multiple trial and error.

In order to verify that multiple deformation segments can achieve multiple deformations, each deformation segment in the deformation unit can be formed with different scanning rates, so that each deformation segment has a different phase transition temperature. A NiTi alloy (NiTi) structure with multi-action properties fabricated by laser selective melting. When preparing the structure, different laser scanning speeds (400, 500, 800 mm/s, respectively) were selected for different parts, but the laser power (120 W), the scanning distance (80 μm), and the thickness of the powder layer (30 μm) were kept unchanged. The main difference between the three circular structures is that the regions corresponding to different laser scanning speeds are different (for example, one is 400, 500, 800 mm/s clockwise, the other is 500, 400, 800 mm/s clockwise, and the last is 400, 500, and 800 mm/s clockwise. Clockwise 800, 500, and 400 mm/s respectively), that is, the arrangement and combination of nickel-titanium alloy (NiTi) parts prepared at different scanning speeds are different. After the three circles were deformed and put into a water bath, the shapes gradually recovered as the temperature increased, indicating that they all have the characteristics of multi-action deformation.

In a preferred embodiment, the deformation segments with different phase transition temperatures are scanned sequentially by laser along the circumferential direction of the deformed inner ring 62, and the adjacent deformation segments with different phase transition temperatures are There is a smooth transition between the crystal phases of the material. Since it is made of the same shape memory alloy, the deformation segments of the deformed inner ring 62 are still integrated, and through laser scanning, the adjacent deformation segments are also heated when scanning the deformation segments, so that the crystal phase between the deformation segments is is a slow change, therefore, no stress concentration will occur at the interface between the deformed segments, so as to ensure the strength of the deformed inner ring 62 in the process of repeated deformation.

The invention adopts the shape memory alloy as the actuating mechanism to change the nozzle area of the control tail nozzle at different temperatures, thereby effectively avoiding the problem of noise without adding excessive weight and complicated mechanism.

Although the specific embodiments of the present invention are described above, those skilled in the art should understand that this is only an illustration, and the protection scope of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principle and essence of the present invention, but these changes and modifications all fall within the protection scope of the present invention.

Claims (16)

1. The utility model provides a jet nozzle, is used for aeroengine, includes a plurality of minutes piece portions, the minute piece portion encloses and establishes into the gas vent of jet nozzle, its characterized in that, the jet nozzle still includes a deformation inner ring of being made by shape memory alloy, wherein, have the kerf between the minute piece portion, deformation inner ring sets up the inboard of minute piece portion, at least a part of deformation inner ring with the kerf coincidence is gone up in the axial direction to drive minute piece portion removal and change the interval of kerf at the temperature deformation state, thereby change the size of the gas vent of jet nozzle.

2. The jet nozzle of claim 1 wherein said slit is in the shape of one or a combination of straight lines, S-shaped slits, and zigzag shapes.

3. The nozzle of claim 1 wherein the shape of the segment is one or a combination of a saw tooth shape, a circular arc shape, and a trapezoidal shape.

4. The nozzle as set forth in claim 1 wherein said deformable inner ring is circumferentially continuous and completely circumferentially shelters from the inside of each of said slits.

5. The jet nozzle of claim 1, wherein the deformable inner ring is in the shape of one or a combination of a cylindrical structure of uniform wall thickness, corrugated plate, and spring.

6. The exhaust nozzle as claimed in claim 1, wherein fitting grooves are formed in inner sides of the respective divided pieces, the fitting grooves each form a fitting ring along a circumferential direction, and the deformable inner ring has a cylindrical shape and is fitted inside the fitting ring.

7. The jet nozzle of claim 1, wherein the deformable inner ring has different circumferential dimensions at a plurality of different temperatures and expands the segment portions to different positions at different temperatures to vary the exhaust port of the jet nozzle to a plurality of different dimensions.

8. The jet nozzle of claim 7, wherein the deformation inner ring achieves deformation of different circumferential dimensions at a plurality of different temperatures from a combination of materials passing through different phase transition points.

9. The nozzle of claim 8 wherein said deformable inner ring is provided with at least two deformable sections, at least two of said deformable sections having different phase transition temperatures.

10. The jet nozzle of claim 9, wherein the shape-changing segments are distributed along a circumference of the deformed inner ring, wherein the shape-changing segments having the same phase transition temperature are uniformly distributed at various locations of the deformed inner ring along the circumference.

11. The nozzle of any one of claims 1 to 10, wherein the deformed inner ring is made by additive manufacturing.

12. The nozzle of claim 11 wherein the deformable inner ring is provided with at least two deformable sections having different transformation temperatures, the deformable sections having different transformation temperatures being formed from the same shape memory alloy using different additive manufacturing process parameters.

13. The jet tip of claim 12, wherein the additive manufacturing process parameter is one or more of a laser power, a scan rate, and a scan pitch, and/or the shape memory alloy is a nickel titanium alloy.

14. The exhaust nozzle according to claim 12, wherein the morphable segments having different transformation temperatures are sequentially scanned circumferentially by the laser, and the material crystal phase between adjacent morphable segments having different transformation temperatures is smoothly transitioned between the adjacent morphable segments having different transformation temperatures.

15. An aircraft engine, characterised in that the aircraft engine comprises a jet nozzle according to any one of claims 1 to 14, wherein the jet nozzle is a culvert nozzle and/or a culvert nozzle of the aircraft engine.

16. An aircraft, characterized in that it comprises one or more aero-engines according to claim 15.

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