A casing structure and an aero-engine

Abstract

The present disclosure relates to the technical field of aero-engine, and particularly provides a casing structure and an aero-engine, wherein the casing structure comprises: a rotating shaft, which is rotationally arranged; a plurality of blades, which are distributed along the circumferential direction of the rotating shaft; a top ring, which is coaxially arranged with the rotating shaft, and the inner wall of the top ring is fixedly connected with the end of the blade away from the rotating shaft; the top ring is provided with a perforation; a casing, which is provided with an air inlet channel for rotationally mounting the rotating shaft; the inner wall of the air inlet channel is provided with an annular groove; the top ring is rotationally arranged at the opening of the annular groove, and the top ring and the annular groove jointly form a casing cavity; an adjusting mechanism, which is located in the casing cavity and is used for dividing the adjusting cavity into a plurality of adjusting cavities with variable shapes; the casing is provided with a plurality of air holes; each adjusting cavity corresponds to at least one air hole, and the adjusting cavity is in communication with the corresponding air hole. The present disclosure is beneficial to improving the working efficiency and stability of the blade.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of aero-engines, and particularly to a casing structure and an aero-engine. BACKGROUND

[0002] The aero-engine compression system, including a fan and a compressor, works on the airflow by rotating and adding power to achieve the effect of pressure increase. However, there are two problems: 1. Blade tip leakage problem. The fan outer casing, relative to the rotating parts such as the fan, is a stationary part. In order to avoid scratching, there will be a certain gap between the fan rotor blade tip and the casing, that is, the blade tip gap. The existence of the blade tip gap causes the leakage flow from the pressure surface side of the blade to the suction surface side in the gap, which 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 the fan, which can cause the performance of the fan to decline, leading to the decline of the thrust of the aero-engine, and even fire, structural damage, etc., which seriously threatens life safety. In actual operation, great efforts are made to avoid aerodynamic instability, so there is still a certain flow range between the instability boundary and the actual working point, that is, the stability margin. If the fan stability margin is insufficient, it is extremely likely to cause instability during operation.

[0003] In the prior art, the blade tip leakage problem is usually solved by using a shrouded rotor blade, that is, the rotor blade tip is connected by an equal-diameter circular cylinder. This design will add an angular area of the blade tip-inner ring surface, and there is a low-energy flow blockage area in the angular area, which is easy to induce aerodynamic instability, resulting in insufficient fan stability margin. SUMMARY

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

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

[0006] a rotating shaft, which is rotationally arranged;

[0007] a plurality of blades, which are distributed along the circumferential direction of the rotating shaft;

[0008] a top ring, which is coaxially arranged with the rotating shaft, and the inner wall of the top ring is fixedly connected with one end of the blade away from the rotating shaft; the top ring is provided with a perforation;

[0009] a casing, which is provided with an air inlet channel for rotationally mounting the rotating shaft; the inner wall of the air inlet channel is provided with an annular groove; the top ring is rotationally arranged at the opening of the annular groove and forms a casing cavity together with the annular groove;

[0010] An adjusting mechanism is arranged in the casing cavity for dividing the casing cavity into a plurality of variable-shape adjusting cavities; the casing is provided with a plurality of air holes; each of the adjusting cavities corresponds to at least one of the air holes, and the adjusting cavities are in communication with 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 adjusting mechanism comprises an adjusting shaft and an adjusting sheet;

[0013] The adjusting shaft is rotatably arranged on the casing and has one end arranged in the adjusting cavity;

[0014] The adjusting sheet is arranged in the adjusting cavity and is fixedly connected with 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 uniformly distributed along the circumferential direction of the annular groove.

[0016] The casing structure as described above, wherein, optionally, the air holes are provided with valves, and the air holes are used for introducing or extracting air into or out of the corresponding adjusting cavities to adjust the airflow velocity of the perforations.

[0017] The casing structure as described above, wherein, optionally, the valves are used for being opened when a signal of a fan working state approaching an instability boundary is received, so as to make external airflow flow to the corresponding adjusting cavities to change the unsteady acoustic response characteristics of the top ring.

[0018] The casing structure as described above, wherein, optionally, the number of the air holes corresponding to each of the adjusting cavities is multiple.

[0019] According to another aspect of the present disclosure, an aero-engine is also provided, which comprises the casing structure according to any one of the above.

[0020] As will be described in detail below, according to the casing structure of the present disclosure, the tip of the blade is fixedly connected with the inner wall of the top ring by arranging the top ring, and the annular groove is arranged on the inner wall of the casing, and the top ring is rotatably arranged at the opening of the annular groove. By arranging the perforations on the top, air can flow through the perforations, avoiding the formation of corner blockage, which is conducive 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 intended to provide further explanation of the subject technology. BRIEF DESCRIPTION OF DRAWINGS

[0022] The above and other objects, features and advantages of the present disclosure will become more apparent from the following detailed description thereof taken in conjunction with the accompanying drawings, in which: The drawings provided in the disclosure and the corresponding descriptions in the specification serve to provide further understanding of the embodiments of the present disclosure, constitute part of the specification, and are used to explain the present disclosure together with the embodiments of the present disclosure, but do not constitute a limitation of the present disclosure. In the drawings, the same reference numerals generally represent the same components or steps.

[0023] Fig. 1 is a front view of the machine case structure according to the present application;

[0024] Fig. 2 is a perspective view of the machine case structure according to the present application;

[0025] Fig. 3 is a partial three-dimensional sectional view of the machine case structure according to the present application;

[0026] Fig. 4 is a partial sectional view of the machine case structure according to the present application.

[0027] 1-rotating shaft, 2-vane, 3-top ring, 4-machine case, 5-adjusting mechanism;

[0028] 31-perforation;

[0029] 41-air inlet passage, 42-annular groove, 43-machine case cavity, 44-air hole;

[0030] 431-adjusting cavity;

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

[0032] In order to make the purposes, technical solutions and advantages of the present disclosure more obvious, the following will describe the example embodiments according to the present disclosure with reference to the drawings. Obviously, the described embodiments are only part of the embodiments of the present disclosure, not all embodiments of the present disclosure, and it should be understood that the present disclosure is not limited by the example embodiments described here.

[0033] In view of the problems proposed in the background art, the present disclosure proposes the following solutions.

[0034] Please refer to Figs. 1 to 4 The present disclosure proposes a machine case structure, which comprises a rotating shaft 1, a vane 2, a top ring 3, a machine case 4 and an adjusting mechanism 5. The rotating shaft 1, the vane and the top ring 3 are all rotating parts, and are rotatably installed in the machine case 4. The adjusting mechanism 5 is installed on the machine case 4.

[0035] Specifically, the rotating shaft 1 is arranged in the casing 4, and the rotating shaft 1 is used for fixing the blades 2. In the actual implementation, the rotating shaft 1 is rotationally connected with the casing 4. The rotation of the rotating shaft 1 is driven by an external driving member.

[0036] The blades 2 are a plurality of blades, and the plurality of 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 the blades 2 are uniformly distributed around the circumferential direction of the rotating shaft 1. The rotation of the blades 2 is driven by the rotation of the rotating shaft 1, and then the air flow is generated to make the air flow 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 with the end of the blade 2 away from the rotating shaft 1. The top ring 3 is provided with a perforation 31. In the actual implementation, the top ring 3 is annular, and the inner wall of the top ring 3 is fixedly connected with the blade tip of the blade 2. More specifically, each of the blades 2 is fixedly connected with the top ring 3. By arranging the perforation 31 on the top ring 3, the formation of the corner area blockage at the position where the top ring 3 is connected with the blade 2 can be prevented. The perforation 31 can form a flow passage in the blocked area, relieve the formation of the corner area blockage, and be beneficial to improving the working efficiency and stability of the blade. By arranging the perforation 31, the impedance of the perforation structure in the acoustic field can be utilized to play a damping role.

[0038] The casing 4 is provided with an air inlet channel 41 for rotationally mounting the rotating shaft 1. The inner wall of the air inlet channel 41 is provided with an annular groove 42. The top ring 3 is rotationally arranged at the opening of the annular groove 42 and forms a casing cavity 43 together with the annular groove 42. That is, the annular groove 42 and the blade 2 have basically the same position in the axial direction. In the actual application, the size of the top ring 3 in the axial direction should be slightly larger than the maximum size of the blade 2 in the axial direction.

[0039] The adjusting mechanism 5 is located in the casing cavity 43 and is used for dividing the casing cavity 43 into a plurality of adjusting cavities 431 with variable shapes. The casing 4 is provided with a plurality of air holes 44. Each of the adjusting cavities 431 corresponds to at least one of the air holes 44, and the adjusting cavity 431 is in communication with the corresponding air hole 44. By the adjusting mechanism 5, the shape of the adjusting cavity 431 can be changed, and by changing the spatial shape of the adjusting cavity 431, the acoustic performance thereof can be further adjusted to absorb the unsteady pressure wave 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 respective 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 the perforation 31 is small, and the absorption effect on the steady 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 the corner area is prone to blockage.

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

[0042] Specifically, the adjusting shaft 51 is rotatably installed on the casing 4 and has one end located in the adjusting cavity 431. The adjusting piece 52 is located in the adjusting cavity 431 and is fixedly connected to the adjusting shaft 51. That is, the shape of the adjusting cavity 431 is changed by rotating the adjusting shaft 51. In actual application, the adjusting shaft 51 can be driven to rotate by an external driving member.

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

[0044] In a specific implementation, in order to dissipate the energy of the instability disturbance wave, in the present disclosure, a valve is arranged on the air hole 44, which is used to introduce or exhaust air into or out of the corresponding adjustment cavity 431, so as to adjust the air flow speed of the perforated top ring 3. In a specific implementation, the number of air holes 44 can be three to five, that is, three to five air holes 44 correspond to each adjustment cavity 431. By actively introducing or exhausting air into the adjustment cavity 431, the unsteady acoustic response characteristics of the perforated top ring are changed, various pressure waves related to instability in the flow field are absorbed, the energy of the instability disturbance wave is dissipated, the working margin is expanded, and instability is avoided. Specifically, the valve is used to open when receiving a signal that the fan working state is close to the instability boundary, so that the external airflow flows into the corresponding adjustment cavity 431, so as 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 real-time monitoring system stability. According to the detection result of the array of wall pressure sensors, when it is identified that the fan working state is close to the instability boundary, a signal that the fan working state is close to the instability boundary is sent to the corresponding valve. In this way, when the fan working state is close to the instability boundary, the control mechanism is started to adjust the blowing and sucking air speed. The blowing and sucking air speed or the air flow speed through the small holes of the perforated top ring caused by blowing and sucking air can change the unsteady acoustic response characteristics of the perforated top ring, absorb various pressure waves related to instability in the flow field, dissipate the energy of the instability disturbance wave, expand the working margin, and avoid instability.

[0045] The present disclosure also provides an aero-engine comprising the casing structure.

[0046] In the present disclosure, the perforations 31 on the top ring 3 have two main functions, one is that the perforations 31 form a through-flow passage for the blocked area caused by the fan blade action, which relieves the blockage and improves the working efficiency and stability of the blade 2. The second is that the perforations 31 have certain acoustic impedance and can play a damping role. In a specific implementation, the perforations 31 can be distributed on both sides of the surface where the blade 2 is located. Since the top ring 3 is a perforated structure and has certain acoustic impedance, the blowing and sucking air forms a bias flow on both sides, which can adjust the impedance characteristics of the perforated structure and form a damping wall. On the one hand, it can purposefully absorb sound waves in the flow field and play a noise reduction role; on the other hand, it can adjust the impedance boundary conditions to affect the stability of the compression system and expand the stability margin.

[0047] The rotation of the shaft 1 works on the airflow, and causes the pressure difference on both sides of the blade tip 2. Under the action of the pressure difference, part of the airflow on the pressure surface side of the rotor blade 2 channel will flow into the adjusting cavity 431 through the perforations 31 of the top ring 3, and then the airflow in the adjusting cavity 431 will flow into the inlet channel 41 from the suction surface side of the blade 2 through the perforations 31. The effect of this flow is: 1. To provide an additional flow passage to alleviate the blockage of the tip endwall area, 2. For the perforations, it is a deflected flow, which can adjust the acoustic response of the perforations 31 to achieve the absorption of the unsteady pressure wave in the flow field. The adjusting piece 52 can adjust the flow state of the airflow in the adjusting cavity 431 to reduce the flow loss. On the other hand, the adjusting cavity 431 is formed by the adjacent adjusting piece 52 and the surface of the top ring 3 and the outer casing wall, which, together with the top ring below, forms an acoustically absorbing structure with a non-local response. By adjusting the angle of the adjusting piece 52, the spatial shape of the adjusting cavity can be changed, and the acoustic performance can be further adjusted to absorb the unsteady pressure wave in the flow field.

[0048] The above describes the basic principles of the present disclosure in combination with specific embodiments, but it should be pointed out that the advantages, advantages, effects and the like mentioned in the present disclosure are only examples and are not limiting, and these advantages, advantages, effects and the like cannot be considered as the various embodiments of the present disclosure must have. In addition, the specific details of the above disclosure are only for the purpose of example and for the purpose of understanding, and are not limiting, and the above details do not limit the present disclosure to the above specific details.

[0049] The block diagrams of the devices, apparatuses, equipment, systems involved in the present disclosure are only illustrative examples and are not intended to require or imply the connection, arrangement, configuration shown in the block diagram. As those skilled in the art will recognize, these devices, apparatuses, equipment, systems can be connected, arranged, configured in any manner. Words such as "include", "contain", "have" and the like are open-ended words, which mean "including but not limited to", and can be used interchangeably. The words "or" and "and" used herein mean the word "and / or", and can be used interchangeably unless the context clearly indicates otherwise. The word "such as" used herein means the phrase "such as but not limited to", and can be used interchangeably.

[0050] In addition, as used herein, "or" used in a list of items, starting with "at least one of the items, indicates a separate list, so that, for example, "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). In addition, the phrase "exemplary" does not mean that the described example is preferred or better than other examples.

[0051] It is also important to note that the systems and methods of the present disclosure can be embodied in a variety of contexts. For example, the systems and methods of the present disclosure can be implemented in the context of a computer system, a mobile device, a server, a network, a distributed computing environment, etc. It is also important to note that the various components and steps of the systems and methods of the present disclosure can be decomposed and / or recombined. Such decompositions and / or recombinations should be considered equivalents of the present disclosure.

[0052] Various changes, modifications, and improvements in the technologies described herein can be made without departing from the teachings of the technologies defined by the appended claims. Moreover, the scope of the claims of the present disclosure is not limited to the specific aspects described above. Rather, the aspects of the present disclosure are intended to encompass all technologies and processes within the scope of the claims, including all technical equivalents, which now or later become known to those skilled in the art. Accordingly, the appended claims are intended to embrace any and all alterations, modifications and improvements of the technologies described herein.

[0053] The above description of the disclosed aspects is given for illustrative purposes only and is not intended to limit the scope of the disclosure. The aspects are presented as examples of the disclosure only and are not intended to limit the scope of the disclosure. Although a number of example aspects and embodiments have been discussed, those of skill in the art will recognize various modifications, alternatives, changes, additions, and subcombinations. It is intended that the disclosure embrace all such modifications, alternatives, changes, additions, and subcombinations as fall within the scope of the claims.

[0054] The above description has been presented for the purposes of illustration and description. Further, this description is not intended to limit the embodiments of the disclosure to the forms disclosed herein. Although various example aspects and embodiments have been discussed above, those of skill in the art will recognize certain variations, modifications, changes, additions, and subcombinations.

Claims

1. A magazine structure, characterized by, The utility model relates to a kind of fan rotor structure, including: Rotary shaft (1), rotation is arranged; Blade (2), the blade (2) is multiple, multiple the blade (2) is distributed along the circumferential direction of rotary shaft (1); Top ring (3), the top ring (3) is coaxially arranged with rotary shaft (1), the inner wall of top ring (3) is fixedly connected with the end of blade (2) away from rotary shaft (1);Perforation (31) is equipped on top ring (3); Machine case (4), the air inlet channel (41) for rotationally installing rotary shaft (1) is equipped on machine case (4);Annular groove (42) is equipped on the inner wall of air inlet channel (41);Top ring (3) is rotationally arranged at the opening of annular groove (42), and annular groove (42) is formed machine case cavity (43) in common with top ring (3); Adjusting mechanism (5), adjusting mechanism (5) is located in machine case cavity (43), for separating machine case cavity (43) into multiple shape-variable adjusting cavities (431);Multiple air holes (44) are equipped on machine case (4);Each adjusting cavity (431) corresponds at least one air hole (44), and adjusting cavity (431) is communicated with corresponding air hole (44).

2. The cartridge structure of claim 1, wherein The perforation rate of top ring (3) is 5% to 30%, and the diameter of perforation (31) is 0.5 to 2 millimeters.

3. The cartridge structure of claim 1, wherein The adjusting mechanism (5) includes adjusting shaft (51) and adjusting sheet (52); The adjusting shaft (51) is rotationally installed on the machine case (4), and one end is located in the adjusting cavity (431); The adjusting sheet (52) is located in adjusting cavity (431), and is fixedly connected with the adjusting shaft (51).

4. The cartridge structure of claim 1, wherein The number of adjusting mechanism (5) is equal to the number of blade (2), and adjusting mechanism (5) is evenly distributed along the circumferential direction of annular groove (42).

5. The cartridge structure of claim 1, wherein Valve is equipped on the air hole (44), and the air hole (44) is used to introduce gas or exhaust gas into corresponding adjusting cavity (431), to adjust the airflow velocity of perforation (31).

6. The cartridge structure of claim 5, wherein The valve is used to open when receiving the signal that fan working state is close to instability boundary, to make external airflow flow to corresponding adjusting cavity (431), to change the unsteady acoustic response characteristics of top ring (3).

7. The cartridge structure of claim 5, wherein The number of air holes (44) corresponding to each adjusting cavity (431) is multiple.

8. An aeroengine characterised in that, The utility model relates to a kind of fan rotor structure, including the machine case structure of any one of claims 1-7.

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