Casing structure and aero-engine

Abstract

The invention relates to the technical field of aero-engines, and particularly provides a cartridge receiver structure and an aero-engine. The number of the blades is multiple, and the multiple blades are distributed in the circumferential direction of the rotating shaft; the top ring and the rotating shaft are coaxially arranged, and the inner wall of the top ring is fixedly connected with the ends, away from the rotating shaft, of the blades; a through hole is formed in the top ring; the cartridge receiver is provided with an air inlet channel for rotationally mounting the rotating shaft; an annular groove is formed in the inner wall of the air inlet channel; the top ring is rotationally arranged at the opening of the annular groove, and forms a casing cavity together with the annular groove; the adjusting mechanism is positioned in the casing cavity and is used for dividing the adjusting cavity into a plurality of adjusting cavities with variable shapes; a plurality of air holes are formed in the cartridge receiver; each adjusting cavity corresponds to at least one air hole and is communicated with the corresponding air hole. The working efficiency and stability of the blade can be improved.

Description

Technical Field

[0001] The present disclosure relates to the technical field of aero-engines, and in particular to a casing structure and an aero-engine. Background Art

[0002] The compression system of an aircraft engine, including a fan and a compressor, works on the airflow by rotating to achieve a supercharging effect. However, there are two problems: 1. Tip leakage. The outer casing of the fan is a stationary part compared to rotating parts such as the fan. To avoid scratches, a certain gap, namely the tip gap, is left between the tip of the fan rotor and the casing. The existence of the tip gap causes leakage flow from the pressure side of the blade to the suction side in the gap. This part of the flow is the main source of fan efficiency loss and the main cause of aerodynamic instability. 2. Aerodynamic instability problem. Rotating stall and surge are two typical aerodynamic instability phenomena of fans, which will cause the fan performance to decline, resulting in a decrease in the thrust of the aircraft engine, and even fire, structural damage, etc., which seriously threaten life safety. In the actual operation process, aerodynamic instability will be avoided as much as possible, so there is a certain flow range between the instability boundary and the actual working point, namely the stability margin. If the fan stability margin is insufficient, it is very likely to become instable during operation.

[0003] In the prior art, crowned rotor blades are usually used to solve the tip leakage problem, that is, the rotor blade tip is connected through a circular ring with the same inner diameter. This design will have an extra corner area between the blade tip and the inner ring surface. There is a low-energy flow blockage area in this corner area, which is easy to induce aerodynamic instability and make the fan stability margin insufficient. Summary of the invention

[0004] The present disclosure is proposed in view of the above problems. The present disclosure provides a casing structure and an aircraft engine.

[0005] According to one aspect of the present disclosure, a casing structure is provided, comprising:

[0006] Axis, rotation setting;

[0007] Blades, the number of the blades is multiple, and the multiple blades are distributed along the circumferential direction of the rotating shaft;

[0008] A top ring, wherein the top ring is coaxially arranged with the rotating shaft, and the inner wall of the top ring is fixedly connected to an end of the blade away from the rotating shaft; and a through hole is provided on the top ring;

[0009] A casing, wherein the casing is provided with an air intake passage for rotatably mounting the rotating shaft; an annular groove is provided on the inner wall of the air intake passage; the top ring is rotatably arranged at the opening of the annular groove, and together with the annular groove forms a casing cavity;

[0010] An adjusting mechanism is located in the casing cavity and is used to divide the casing cavity into a plurality of adjusting cavities with variable shapes; a plurality of air holes are provided on the casing; each of the adjusting cavities corresponds to at least one of the air holes, and the adjusting cavities are connected to the corresponding air holes.

[0011] The casing structure as described above, wherein optionally, the perforation rate of the top ring is 5% to 30%, and the perforation diameter is 0.5 to 2 mm.

[0012] The casing structure as described above, wherein, optionally, the adjustment mechanism comprises an adjustment shaft and an adjustment sheet;

[0013] The adjusting shaft is rotatably mounted on the casing, and one end of the adjusting shaft is located in the adjusting cavity;

[0014] The adjusting sheet is located in the adjusting cavity and is fixedly connected to the adjusting shaft.

[0015] The casing structure as described above, wherein, optionally, the number of the adjusting mechanisms is equal to the number of the blades, and the adjusting mechanisms are evenly distributed along the circumferential direction of the annular groove.

[0016] In the casing structure as described above, optionally, a valve is provided on the air hole, and the air hole is used to introduce gas into or absorb gas from the corresponding regulating cavity to adjust the air flow speed of the perforation.

[0017] The casing structure as described above, wherein, optionally, the valve is used to open upon receiving a signal that the fan operating state is on the verge of an instability boundary, so as to allow external airflow to flow to the corresponding regulating cavity to change the unsteady acoustic response characteristics of the top ring.

[0018] The casing structure as described above, wherein, optionally, each regulating cavity corresponds to a plurality of air holes.

[0019] According to another aspect of the present disclosure, an aircraft engine is also proposed, which includes the casing structure described in any one of the above items.

[0020] As will be described in detail below, according to the casing structure of the embodiment of the present disclosure, by providing a top ring, the blade tip of the blade is fixedly connected to the inner wall of the top ring, and an annular groove is provided on the inner wall of the casing, and the top ring is rotatably provided at the opening of the annular groove. By providing a perforation on the top, air can flow through the perforation, avoiding blockage in the corner area, which is beneficial to improving the working efficiency and stability of the blade.

[0021] It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the technology as claimed. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and other purposes, features and advantages of the present disclosure will become more apparent by describing the embodiments of the present disclosure in more detail in conjunction with the accompanying drawings. The accompanying drawings are used to provide a further understanding of the embodiments of the present disclosure and constitute a part of the specification. Together with the embodiments of the present disclosure, they are used to explain the present disclosure and do not constitute a limitation of the present disclosure. In the accompanying drawings, the same reference numerals generally represent the same components or steps.

[0023] Figure 1 It is a front view of the casing structure proposed by the present invention;

[0024] Figure 2 It is a three-dimensional diagram of the casing structure proposed by the present invention;

[0025] Figure 3 It is a partial three-dimensional cross-sectional view of the casing structure proposed by the present invention;

[0026] Figure 4 It is a partial cross-sectional view of the casing structure proposed by the present invention.

[0027] 1-rotating shaft, 2-blades, 3-top ring, 4-casing, 5-adjusting mechanism;

[0028] 31-perforation;

[0029] 41-intake channel, 42-annular groove, 43-casing cavity, 44-air hole;

[0030] 431-adjustment chamber;

[0031] 51-adjusting shaft, 52-adjusting sheet. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solution and advantages of the present disclosure more obvious, the exemplary embodiments according to the present disclosure will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all the embodiments of the present disclosure, and it should be understood that the present disclosure is not limited to the exemplary embodiments described here.

[0033] In response to the problems raised in the background technology, the present disclosure proposes the following solutions.

[0034] Please refer to Figures 1 to 4 The present disclosure proposes a casing structure, which includes: a rotating shaft 1, blades 2, a top ring 3, a casing 4 and an adjustment mechanism 5. The rotating shaft 1, the blades and the top ring 3 are all rotating parts, which are rotatably installed in the casing 4, and the adjustment mechanism 5 is installed on the casing 4.

[0035] Specifically, the rotating shaft 1 is rotatably disposed in the casing 4, and the rotating shaft 1 is used to fix the blades 2. In a specific implementation, the rotating shaft 1 is rotatably connected to the casing 4. The rotation of the rotating shaft 1 is driven by an external driving member.

[0036] There are multiple blades 2, and the multiple blades 2 are distributed along the circumferential direction of the rotating shaft 1; in some implementations, the number of blades 2 can be 10 to 30, and they are evenly distributed around the circumferential direction of the rotating shaft 1. The rotation of the rotating shaft 1 drives the blades 2 to rotate, thereby causing air to flow, so that the airflow flows along the air inlet channel 41 in the casing 4.

[0037] The top ring 3 is coaxially arranged with the rotating shaft 1, and the inner wall of the top ring 3 is fixedly connected to the end of the blade 2 away from the rotating shaft 1; the top ring 3 is provided with a perforation 31; in a specific implementation, the top ring 3 is annular, and its inner wall is fixedly connected to the tip of the blade 2, and more specifically, each of the blades 2 is fixedly connected to the top ring 3. By providing the perforation 31 on the top ring 3, it is possible to prevent the corner blockage from forming at the position where the top ring 3 and the blade 2 are connected, and the perforation 31 can form a flow channel in the blocked area, alleviate the formation of corner blockage, and help improve the working efficiency and stability of the blade. By providing the perforation 31, the acoustic impedance of the perforated structure can be utilized, thereby playing a damping role.

[0038] The casing 4 is provided with an air inlet passage 41 for rotatably mounting the rotating shaft 1; an annular groove 42 is provided on the inner wall of the air inlet passage 41; the top ring 3 is rotatably arranged at the opening of the annular groove 42, and together with the annular groove 42 forms a casing cavity 43. That is, the annular groove 42 and the blade 2 are at substantially the same position in the axial direction. In practical applications, the dimension of the top ring 3 along the axial direction should be slightly larger than the maximum dimension of the blade 2 in the axial direction.

[0039] The adjustment mechanism 5 is located in the casing cavity 43, and is used to divide the casing cavity 43 into a plurality of adjustable cavities 431 with variable shapes; the casing 4 is provided with a plurality of air holes 44; each of the adjustable cavities 431 corresponds to at least one of the air holes 44, and the adjustable cavities 431 are connected to the corresponding air holes 44. The shape of the adjustable cavity 431 can be changed by the adjustment mechanism 5, and the acoustic performance of the adjustable cavity 431 can be further adjusted by changing the spatial shape of the adjustable cavity 431, so as to absorb the unsteady pressure waves in the field.

[0040] In a specific implementation, the perforation rate of the top ring 3 is 5% to 30%, and the diameter of the perforation 31 is 0.5 to 2 mm. That is, the sum of the areas of the perforations on the top ring 3 accounts for 5% to 30% of the inner wall surface of the top ring 3. The diameter of the perforation 31 is preferably 1 mm. If the diameter of the perforation 31 is too large, the damping generated by it becomes smaller, and the absorption effect on the stationary wave is reduced; if the diameter of the perforation 31 is too small, the airflow is not easy to pass through the perforation 31, and it is easy to form a corner blockage.

[0041] In the specific implementation, in order to better absorb the unsteady pressure waves in the flow field, the present disclosure further improves the adjustment mechanism 5. Specifically, the adjustment mechanism 5 includes an adjustment shaft 51 and an adjustment sheet 52. The adjustment shaft 51 can be controlled by an external actuator to achieve control of the adjustment sheet 52. The adjustment sheet 52 changes the shape of the adjustment cavity 431 by rotating itself. It should be pointed out that adjacent adjustment cavities 431 are not necessarily completely isolated, that is, the adjustment sheet 52 is not completely fitted with the top ring 3 or the annular groove 42. There may be a gap between the adjustment sheet 52 and the top ring 3, and there may also be a gap between the adjustment sheet 52 and the annular groove 42.

[0042] Specifically, the adjustment shaft 51 is rotatably mounted on the casing 4, and one end of the adjustment shaft 51 is located in the adjustment cavity 431. The adjustment sheet 52 is located in the adjustment cavity 431 and is fixedly connected to the adjustment shaft 51. That is, the shape of the adjustment cavity 431 is changed by the rotation of the adjustment shaft 51. In practical applications, the adjustment shaft 51 can be driven to rotate by an external driving member.

[0043] In a specific implementation, the number of the adjustment mechanisms 5 is equal to the number of the blades 2, and the adjustment mechanisms 5 are evenly distributed along the circumferential direction of the annular groove 42. For example, in some implementations, when the number of blades 2 is 22, the number of the adjustment mechanisms 5 is also 22, and the 22 adjustment mechanisms 5 are evenly distributed along the circumferential direction of the casing 4.

[0044] In the specific implementation, in order to dissipate the energy of the unstable disturbance wave, in the present disclosure, a valve is provided on the air hole 44, and the air hole 44 is used to pass gas into or suck out gas into the corresponding regulating chamber 431 to adjust the air flow speed of the perforation 31. In the specific implementation, the number of the air holes 44 can be multiple, such as three to five, that is, each regulating chamber 431 corresponds to three to five air holes 44. By actively passing or sucking out gas into the regulating chamber 431, the unsteady acoustic response characteristics of the perforated top ring are changed to absorb various pressure waves related to instability in the flow field, dissipate the energy of the unstable disturbance wave, thereby expanding the working margin and avoiding instability. Specifically, the valve is used to open when receiving a signal that the fan working state is on the verge of an unstable boundary, so that the external airflow flows to the corresponding regulating chamber 431 to change the unsteady acoustic response characteristics of the top ring 3. That is, the wall pressure sensor array can be used to detect the flow state inside the fan, and the signal is transmitted to the early warning system to monitor the system stability in real time. According to the detection results of the array of wall pressure sensors, when it is identified that the working state of the fan is on the verge of the instability boundary, a signal that the working state of the fan is on the verge of the instability boundary is sent to the corresponding valve. In this way, when the working state of the fan is on the verge of the instability boundary, the control mechanism is started to adjust the blowing and suction speed. This blowing and suction speed, or the air flow speed flowing through the small holes of the perforated top ring due to blowing and suction, can change the unsteady acoustic response characteristics of the perforated top ring to absorb various pressure waves related to instability in the flow field, realize the dissipation of the energy of the instability disturbance wave, thereby expanding the working margin and avoiding instability.

[0045] The present disclosure also provides an aircraft engine, comprising the casing structure provided by the present disclosure.

[0046] In the present disclosure, the perforations 31 on the top ring 3 have two main functions. First, the action of the fan blades will cause blockage in the corner area. The perforations 31 form a flow channel for the blocked area to alleviate the blockage and improve the working efficiency and stability of the blades 2. Second, the perforations 31 have a certain impedance in acoustics and can play a damping role. In specific implementation, the perforations 31 can be distributed on both sides of the surface where the blades 2 are located. Since the top ring 3 is a perforated structure with a certain acoustic impedance, and since the blowing and suction air form a biased flow on both sides thereof, the impedance characteristics of the perforated structure can be adjusted to form a damping wall surface. On the one hand, it can purposefully absorb the sound waves of the flow field and play a role in noise reduction; on the other hand, it can affect the stability of the compression system and expand the stability margin by adjusting the impedance boundary conditions.

[0047] Since the rotating shaft 1 works on the airflow, a pressure difference is formed on both sides of the blade 2, especially the blade tip. Under the action of the pressure difference, part of the airflow on the pressure side of the channel of the rotor blade 2 will flow into the regulating chamber 431 through the perforation 31 of the top ring 3, and then the airflow in the regulating chamber 431 will flow into the intake channel 41 from the suction side of the blade 2 through the perforation 31. The role of this flow is: 1. Provide an additional flow path to alleviate the blockage of the tip wall area of ​​the blade 2, 2. For the perforation, this is a bias flow, which can adjust the acoustic response of the perforation 31 and realize the absorption of the unsteady pressure wave of the flow field. The regulating sheet 52 can adjust the flow state of the airflow in the cavity 431 and reduce the flow loss. On the other hand, the adjacent regulating sheets 52 and the top ring 3 and the outer casing wall form the regulating chamber 431, which, together with the top ring below, forms an acoustic sound absorption structure with non-local response. By adjusting the angle of the regulating sheet 52, the spatial shape of the regulating chamber can be changed, and the acoustic performance can be further adjusted, thereby absorbing the unsteady pressure wave in the flow field.

[0048] The basic principles of the present disclosure are described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, effects, etc. mentioned in the present disclosure are only examples and not limitations, and it cannot be considered that these advantages, strengths, effects, etc. are required by each embodiment of the present disclosure. In addition, the specific details disclosed above are only for the purpose of illustration and ease of understanding, and are not limitations. The above details do not limit the present disclosure to the necessity of adopting the above specific details to be implemented.

[0049] The block diagrams of the devices, apparatuses, equipment, and systems involved in this disclosure are only illustrative examples and are not intended to require or imply that they must be connected, arranged, and configured in the manner shown in the block diagrams. As will be appreciated by those skilled in the art, these devices, apparatuses, equipment, and systems can be connected, arranged, and configured in any manner. Words such as "including," "comprising," "having," and the like are open words, referring to "including but not limited to," and can be used interchangeably therewith. The words "or" and "and" used herein refer to the words "and / or," and can be used interchangeably therewith, unless the context clearly indicates otherwise. The word "such as" used herein refers to the phrase "such as but not limited to," and can be used interchangeably therewith.

[0050] Additionally, as used herein, "or" used in a list of items beginning with "at least one" indicates a separate list, so that, for example, a list of "at least one of A, B, or C" means A or B or C, or AB or AC or BC, or ABC (i.e., A and B and C). Furthermore, the word "exemplary" does not mean that the example described is preferred or better than other examples.

[0051] It should also be noted that in the system and method of the present disclosure, each component or each step can be decomposed and / or recombined. Such decomposition and / or recombination should be regarded as equivalent solutions of the present disclosure.

[0052] Various changes, substitutions, and modifications of the techniques described herein may be made without departing from the teachings defined by the appended claims. Furthermore, the scope of the claims of the present disclosure is not limited to the specific aspects of the processes, machines, manufactures, compositions of events, means, methods, and actions described above. Currently existing or later to be developed processes, machines, manufactures, compositions of events, means, methods, or actions that perform substantially the same functions or achieve substantially the same results as the corresponding aspects described herein may be utilized. Thus, the appended claims include such processes, machines, manufactures, compositions of events, means, methods, or actions within their scope.

[0053] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of the present disclosure. Therefore, the present disclosure is not intended to be limited to the aspects shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

[0054] The above description has been given for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present disclosure to the forms disclosed herein. Although multiple example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof.

Claims

1. A casing structure, characterized in that: include: A rotating shaft (1), which is arranged to rotate; Blades (2), the number of the blades (2) is multiple, and the multiple blades (2) are distributed along the circumferential direction of the rotating shaft (1); A top ring (3), wherein the top ring (3) is coaxially arranged with the rotating shaft (1), and an inner wall of the top ring (3) is fixedly connected to an end of the blade (2) away from the rotating shaft (1); a through hole (31) is provided on the top ring (3); A casing (4), wherein the casing (4) is provided with an air intake channel (41) for rotatably mounting the rotating shaft (1); an annular groove (42) is provided on the inner wall of the air intake channel (41); the top ring (3) is rotatably arranged at the opening of the annular groove (42), and together with the annular groove (42) forms a casing cavity (43); An adjusting mechanism (5), the adjusting mechanism (5) being located in the casing cavity (43) and being used for dividing the casing cavity (43) into a plurality of adjusting cavities (431) of variable shape; a plurality of air holes (44) being provided on the casing (4); each of the adjusting cavities (431) corresponding to at least one of the air holes (44), and the adjusting cavities (431) being in communication with the corresponding air holes (44).

2. The casing structure according to claim 1, characterized in that: The perforation rate of the top ring (3) is 5% to 30%, and the diameter of the perforation (31) is 0.5 to 2 mm.

3. The casing structure according to claim 1, characterized in that: The adjustment mechanism (5) comprises an adjustment shaft (51) and an adjustment sheet (52); The adjusting shaft (51) is rotatably mounted on the casing (4), and one end of the adjusting shaft is located in the adjusting cavity (431); The adjustment sheet (52) is located in the adjustment cavity (431) and is fixedly connected to the adjustment shaft (51).

4. The casing structure according to claim 1, characterized in that: The number of the adjustment mechanisms (5) is equal to the number of the blades (2), and the adjustment mechanisms (5) are evenly distributed along the circumferential direction of the annular groove (42).

5. The casing structure according to claim 1, characterized in that: The air hole (44) is provided with a valve, and the air hole (44) is used to pass gas into or suck out gas from the corresponding regulating cavity (431) to adjust the air flow speed of the through hole (31).

6. The casing structure according to claim 5, characterized in that: The valve is used to open when receiving a signal that the fan operating state is on the verge of an instability boundary, so as to allow the external airflow to flow to the corresponding adjustment cavity (431) to change the unsteady acoustic response characteristics of the top ring (3).

7. The casing structure according to claim 5, characterized in that: The number of air holes (44) corresponding to each of the regulating chambers (431) is multiple.

8. An aircraft engine, characterized in that: The invention comprises the casing structure as described in any one of claims 1 to 7.

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