CN113187763A

CN113187763A - Impeller machine and aircraft engine

Info

Publication number: CN113187763A
Application number: CN202010036033.7A
Authority: CN
Inventors: 刘鹏
Original assignee: AECC Commercial Aircraft Engine Co Ltd
Current assignee: AECC Commercial Aircraft Engine Co Ltd
Priority date: 2020-01-14
Filing date: 2020-01-14
Publication date: 2021-07-30

Abstract

The invention discloses an impeller machine and an aircraft engine, wherein the impeller machine is provided with an air inlet side and an air outlet side, and is characterized by comprising the following components: the rotor comprises a rotating shaft and blades arranged on the rotating shaft; a casing surrounding the rotor radially outside the blades; the circumferential air leakage prevention structure comprises a plurality of sealing teeth which are arranged on the inner wall of the shell and positioned in a blade tip clearance between the blade tip and the inner wall of the shell, and the sealing teeth extend along the direction from the air inlet side to the air outlet side. The impeller mechanism can reduce the gas leakage in the circumferential gap of the impeller mechanism when the gas passes through the impeller mechanism.

Description

Impeller machine and aircraft engine

Technical Field

The invention relates to the technical field of engines, in particular to an impeller machine and an aero-engine.

Background

The engine has a turbo machine for passing gas, such as a compressor for applying work to the gas and a turbine for receiving the gas to apply work, and in operation, in order to prevent the rotor blades from rubbing against the casing provided at the periphery of the blades, a certain gap, i.e., a blade tip gap, is provided between the tip of the rotor, i.e., the end surface of the blade tip of the blade, and the inner wall of the casing. The performance of an engine is greatly influenced by the size of a gap between the blade tip and the casing of a rotor blade of the impeller machine, the blade tip gap is leaked and flows due to the overlarge gap, and the integral performance of the engine is not favorable due to the generation of blade tip gap leakage vortex accompanied with flow loss. The clearance is too small, so that the collision and abrasion between the rotor of the gas compressor and the inner wall of the shell are easy to occur, the blade tips or the shell are abraded, and great difficulty is brought to later maintenance. In severe cases, this can lead to rotor blade breakage and may even compromise aviation safety. Therefore, how to reduce the gas gap leakage between the blade tip and the inner wall of the shell when the blade tip gap exists between the blade tip and the inner wall of the shell is a problem to be solved.

Disclosure of Invention

The purpose of the present invention is to provide an impeller machine that can reduce the leakage of gas through gaps in the circumferential direction of the impeller machine when the gas passes through the impeller machine.

The invention discloses an impeller machine, which is provided with an air inlet side and an air outlet side and comprises:

the rotor comprises a rotating shaft and blades arranged on the rotating shaft;

a casing surrounding the rotor radially outside the blades;

the circumferential air leakage prevention structure comprises a plurality of sealing teeth which are arranged on the inner wall of the shell and positioned in a blade tip clearance between the blade tip and the inner wall of the shell, and the sealing teeth extend along the direction from the air inlet side to the air outlet side.

In some embodiments of the present invention, the,

the impeller machine is a gas compressor, and the extending direction of the sealing tooth from the root part on the inner wall of the shell to the free end far away from the inner wall of the shell inclines along the rotating direction of a rotor of the gas compressor when the rotor works; or

The impeller machine is a turbine, and the extending direction of the root part of the sealing tooth on the inner wall of the shell to the free end far away from the inner wall of the shell is inclined against the rotating direction of the turbine rotor during working.

In some embodiments, the turbomachinery includes a wear layer disposed on an inner wall of the casing, the wear layer including the circumferential air leakage prevention structure.

In some embodiments, the two ends of the seal tooth are located outside the two ends of the tip of the blade, respectively, in the axial direction of the turbomachine.

In a second aspect, the invention discloses an aircraft engine comprising the impeller machine.

According to the impeller machine provided by the invention, the plurality of sealing teeth extending from the air inlet side to the air outlet side are arranged on the inner wall of the shell, and the tooth grooves are formed between the sealing teeth, so that when gas passes through the blade of the impeller machine and gas with larger high-pressure side pressure of the blade leaks to the low-pressure side of the blade along the circumferential direction through the blade tip gap, the gas with larger pressure can enter the tooth grooves of the adjacent sealing teeth, and a higher gas pressure area is formed near the tooth grooves, so that the gas at the high-pressure side of the blade flows to the low-pressure side of the blade is blocked, and the circumferential leakage of the gas of the impeller machine is reduced.

The aero-engine provided by the embodiment of the invention also has corresponding beneficial effects.

Other features of the present invention and advantages thereof will become apparent from the following detailed description of exemplary embodiments thereof, which proceeds with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the invention without limiting the invention. In the drawings:

FIG. 1 is a schematic structural view of an impeller machine according to an embodiment of the present invention;

fig. 2 is an enlarged partial structural view of a portion H of the turbo machine shown in fig. 1.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise. Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

Spatially relative terms, such as "above … …," "above … …," "above … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

As shown in fig. 1 and 2, the impeller machine of the present embodiment has an air inlet side and an air outlet side, and includes a rotor, a casing 1, and a circumferential air leakage preventing structure 3.

The rotor comprises a rotating shaft and blades 2 arranged on the rotating shaft. The casing 1 surrounds the rotor radially outside the blades 2. In the embodiment shown in fig. 1, the plurality of blades 2 are uniformly distributed on the rotating shaft, and the housing 1 is a circular frame.

The air inlet side and the air outlet side are positioned at two axial ends of the impeller machine, and air flows into the impeller machine from the air inlet side of the impeller machine, interacts with blades of the impeller machine and then flows out from the air outlet side of the impeller machine. The interaction of the gas and the blades may be the work of the blades on the gas, such as the blades of a compressor compressing air, or the work of the gas on the blades, such as the work of the gas on the blades of a turbine, so that the turbine rotates to work outwards.

The circumferential air leakage preventing structure 3 comprises a plurality of sealing teeth 31 which are arranged on the inner wall of the shell 1 and are positioned in a blade tip gap between the blade tip of the blade 2 and the inner wall of the shell 1, and the sealing teeth 31 extend along the direction from the air inlet side to the air outlet side. The sealing teeth 31 are located on the inner wall of the housing 1, i.e. the sealing teeth 31 may be located directly on the inner wall surface of the housing 1, or may be connected to the inner wall surface of the housing 1 through other intermediate media. As shown in fig. 1 and 2, the seal teeth 31 extend along the direction from the air inlet side to the air outlet side, and the extending direction of the seal teeth 31 may be parallel to the axial direction of the impeller machine or may not be perpendicular to the axial direction of the impeller machine.

When the gas interacts with the blade, there will be a pressure difference between the gas adjacent to both sides of the blade, i.e. the two sides of the blade will be divided into a high pressure side 21 adjacent to the gas with the higher pressure and a low pressure side 22 adjacent to the gas with the lower pressure. For example, as shown in fig. 1, in the compressor, along the rotation direction of the blade (the direction indicated by the y arrow in fig. 1), the downstream side of the blade, i.e., the side on which the pressure surface of the compressed gas of the blade is located, is the high-pressure side 21, the upstream side of the blade is the low-pressure side 22, and the gas located on the high-pressure side 21 leaks from the tip clearance to the low-pressure side 22 in the circumferential direction (the direction indicated by the x arrow in fig. 1, and the direction of the x arrow is opposite to the direction of the y arrow in the compressor). As shown in fig. 1, in the impeller machine of the present embodiment, the plurality of seal teeth 31 extending from the inlet side to the outlet side are provided on the inner wall of the casing 1, and tooth grooves are formed between adjacent seal teeth 31, so that when gas passes through the blade of the impeller machine, when the gas with a relatively high pressure on the high pressure side 21 of the blade leaks to the low pressure side 22 of the blade in the circumferential direction through the blade tip gap, the gas with a relatively high pressure enters the tooth grooves of the adjacent seal teeth, and a relatively high gas pressure region is formed near the tooth grooves, thereby blocking the gas on the high pressure side 21 of the blade from flowing to the low pressure side 22 of the blade, and reducing the circumferential leakage of the gas of the impeller machine.

In some embodiments, as shown in fig. 1 and 2, the turbomachinery is a compressor. The direction of extension of the root of the seal tooth 31 on the inner wall of the casing 1 to the free end far from the inner wall of the casing 1 is inclined along the direction of rotation of the compressor rotor during operation, i.e. the direction of extension of the root to the tooth tip of the seal tooth 31 is inclined in the downstream direction of the direction of rotation of the rotor with respect to the radial direction of the turbomachine, i.e. when a certain blade 2 is facing the seal tooth 31, the direction of extension of the root to the tooth tip of the seal tooth 31 is inclined towards the high pressure side 21 of the blade 2 (at this time, the direction of flow of gas from the high pressure side 21 to the low pressure side, i.e. the direction of the x arrow, is opposite to the direction of rotation of the rotor, i.e. the direction of the y arrow). As shown in fig. 2, the arrangement can make the opening of the gullet inclined toward the high pressure side 21 of the blade 2, when the gas with higher pressure on the high pressure side 21 leaks toward the low pressure side of the blade, the gas will flow into the gullet as shown by arrow Z shown in fig. 2, and will flow back along the gullet wall after entering the gullet, because the seal teeth 31 incline toward the high pressure side 21, the gas will flow back toward the high pressure side 21, thereby reducing the leakage of the gas on the high pressure side 21 toward the low pressure side 22, and the backflow gas will also prevent the flow of the gas flowing toward the low pressure side 22 from other high pressure sides 21, further reducing the circumferential leakage of the gas of the impeller machine.

In some embodiments, the turbomachine is a turbine, and the extension of the root of the seal tooth 31 on the inner wall of the casing 1 to the free end remote from the inner wall of the casing 1 is inclined against the direction of rotation of the turbine rotor when in operation. That is, the extending direction from the root to the tip of the seal tooth 31 is inclined in the upstream direction of the rotation direction of the rotor with respect to the radial direction of the turbo machine, that is, when a certain blade 2 faces the seal tooth 31, the extending direction from the root to the tip of the seal tooth 31 is inclined toward the high pressure side 21 of the blade 2 (in this case, the direction of the x arrow, which is the direction in which gas flows from the high pressure side 21 to the low pressure side, is the same as the direction of the y arrow, which is the rotation direction of the rotor). As shown in fig. 2, the arrangement can make the opening of the gullet inclined towards the high pressure side 21 of the blade 2, when the gas with higher pressure at the high pressure side 21 leaks towards the low pressure side of the blade, the gas will flow into the gullet as shown by arrow Z shown in fig. 2, and will flow back along the gullet wall after entering the gullet, because the seal teeth 31 incline towards the high pressure side 21, the gas will flow back towards the high pressure side 21, thus reducing the leakage of the gas at the high pressure side 21 towards the low pressure side 22, and the backflow gas can also prevent the flow of the gas flowing from other high pressure sides 21 towards the low pressure side 22, further reducing the circumferential leakage of the gas of the impeller machine.

In some embodiments, the turbomachinery comprises a wear layer provided on the inner wall of the casing 1, the wear layer comprising circumferential air leakage prevention structures 3. As shown in fig. 1, the circumferential air leakage preventing structure 3 of the present embodiment is a wear-resistant layer structure disposed on the inner wall of the housing 1, the wear-resistant layer structure of the present embodiment is different from a smooth wear-resistant layer structure of the prior art, and the present embodiment is a wear-resistant layer structure with a sealing tooth shape, and has a better circumferential air leakage preventing effect while having a wear-resistant effect. Meanwhile, the wear-resistant layer with the sealing teeth 31 only needs to be subjected to sawtooth-shaped cutting on the basis of the smooth wear-resistant layer structure in the prior art, and the process method is simple.

In some embodiments, the two ends of the seal tooth 31 are located outside the two ends of the tip of the blade 2 in the axial direction of the turbomachine. That is, the axial length of the seal tooth 31 is greater than the axial length of the blade tip of the blade 2, and the seal tooth 31 can completely cover the blade tip, so that the seal tooth 31 can reduce the circumferential leakage of the gas of the blade tip in the whole axial range, improve the range of reducing gas leakage, and improve the effect of reducing leakage.

In some embodiments, an aircraft engine is disclosed that includes the above-described impeller machine.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention and not to limit it; although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art will understand that: modifications to the specific embodiments of the invention or equivalent substitutions for parts of the technical features may be made; without departing from the spirit of the present invention, it is intended to cover all aspects of the invention as defined by the appended claims.

Claims

1. A turbomachinery having an intake side and an exhaust side, comprising:

the rotor comprises a rotating shaft and blades (2) arranged on the rotating shaft;

a casing (1) surrounding the rotor radially outside the blades (2);

the circumferential air leakage prevention structure (3) comprises a plurality of sealing teeth (3) which are arranged on the inner wall of the shell (1) and located in blade tip gaps between blade tips of the blades (2) and the inner wall of the shell (1), and the sealing teeth (3) extend in the direction from the air inlet side to the air outlet side.

2. The turbomachinery of claim 1,

the impeller machinery is a gas compressor, and the extending direction of the sealing tooth (3) from the root part on the inner wall of the shell (1) to the free end far away from the inner wall of the shell (1) inclines along the rotating direction of the gas compressor rotor during working; or

The impeller machine is a turbine, and the extending direction of the root part of the sealing tooth (3) on the inner wall of the shell (1) to the free end far away from the inner wall of the shell (1) is inclined against the rotating direction of the turbine rotor during working.

3. The turbomachinery of claim 1, wherein it comprises a wear layer provided on the inner wall of the casing (1), said wear layer comprising said circumferential air leakage prevention structure (3).

4. The turbomachinery of any one of claims 1 to 3, wherein, in the axial direction of the turbomachinery, both ends of the seal tooth (3) are located outside both ends of the tip of the blade (2), respectively.

5. An aircraft engine, characterized in that it comprises a turbomachine according to any one of claims 1 to 4.