CN111287993B

CN111287993B - Axial flow compressor

Info

Publication number: CN111287993B
Application number: CN201811504022.6A
Authority: CN
Inventors: 刘佳骏
Original assignee: AECC Commercial Aircraft Engine Co Ltd
Current assignee: AECC Commercial Aircraft Engine Co Ltd
Priority date: 2018-12-10
Filing date: 2018-12-10
Publication date: 2021-07-30
Anticipated expiration: 2038-12-10
Also published as: CN111287993A

Abstract

The present invention relates to an axial flow compressor. The axial compressor comprises a rotor as a rotating shaft and a rotor blade row which is installed on the rotor and is configured along the circumferential direction of the rotating shaft, wherein the rotor blade row comprises a plurality of rotor blades configured along the circumferential direction of the rotating shaft; the axial flow compressor also comprises a guide rotor blade row which is arranged on the rotor and is configured along the circumferential direction of the rotating shaft, and the guide rotor blade row comprises a plurality of guide rotor blades which are configured along the circumferential direction of the rotating shaft; in the direction of the air flow in the axial compressor, the guide rotor blade row is arranged in front of the rotor blade row, and the camber line of the blade body cross section of the guide rotor blade has a direction of curvature opposite to the direction of curvature of the camber line of the blade body cross section of the rotor blade. The invention provides an axial flow compressor, which can effectively improve the pneumatic stability of the axial flow compressor.

Description

Axial flow compressor

Technical Field

The invention relates to the technical field of impeller machinery, in particular to an axial flow compressor.

Background

Because the rotating blade row of the axial flow compressor rotates at high speed when in work and is prevented from being broken under the action of centrifugal force and pneumatic force, the rotor blade row of the existing axial flow compressor adopts a structure scheme with unadjustable geometry, namely, the direction of airflow flowing to the rotor blade row is changed when the working state of the compressor is changed, but the geometric angle of an inlet of a rotor blade is fixed and unchanged, so that the flow direction of the gas and the geometry of the blade are not coordinated, and particularly, when the attack angle of the airflow at the inlet of the rotor blade is larger, the rotating stall or surge of the compressor is caused, so that the compressor cannot work normally.

In order to reduce the geometric incompatibility of the aerodynamics and the blades and improve the aerodynamic performance of the compressor, the conventional axial flow compressor, particularly an aircraft engine, frequently adopts an inlet guide stator blade row, or the inlet guide stator blade row and other stator blade rows are designed to be adjustable, namely the installation angle of the blade row can be changed according to the working state, so that the change of the inlet airflow direction of the rotor blades is realized.

In order to change the installation angle of the conventional adjustable guide vane or stator vane, an additional adjusting mechanism needs to be added. Secondly, in order to effectively reduce the degree of incompatibility between the gas flow direction and the blade geometry under different conditions, the guide blades and the stator blades should have a plurality of installation angles and even be adjusted arbitrarily within a certain range. In addition, the airflow direction at the inlet of the rotor blade is influenced by three factors, namely the airflow direction at the outlet of the guide vane or the stator blade, the rotating speed of the compressor, the airflow flowing through the compressor and the like, and the numerical value of the installation angle adjustment of the guide vane and the stator blade is determined according to the rotating speed and the flow of the compressor in the current working state, so that the complexity of an adjusting system is greatly increased. Therefore, in practical application, in order to reduce the structural weight and the complexity of the adjusting system, the adjustment of the guide vane or the stator vane cannot be multi-stage or stepless adjusted along with the change of the working state of the compressor, and even the guide vane or the stator vane can only work under two installation angles, which greatly affects the practical effect.

Disclosure of Invention

In view of the above problems in the prior art, the present invention provides an axial compressor, which can effectively improve the aerodynamic stability of the axial compressor.

Specifically, the present invention provides an axial flow compressor having a rotor as a rotating shaft and a rotor blade row mounted on the rotor and arranged in a circumferential direction of the rotating shaft, the rotor blade row including a plurality of rotor blades arranged in the circumferential direction of the rotating shaft;

the axial flow compressor further comprises a guide rotor blade row which is installed on the rotor and configured along the circumferential direction of the rotating shaft, wherein the guide rotor blade row comprises a plurality of guide rotor blades configured along the circumferential direction of the rotating shaft;

in the direction of air flow in the axial flow compressor, the guide rotor blade row is disposed in front of the rotor blade row, and the camber line of the blade body cross section of the guide rotor blade has a direction of curvature opposite to the direction of curvature of the camber line of the blade body cross section of the rotor blade.

According to an embodiment of the invention, the inlet geometry angle of the guide rotor blade is not smaller than the outlet geometry angle, with the reference being defined at the angle of the frontal line.

According to an embodiment of the invention, the turning angle of the guide rotor blade is 0 ° to 20 °.

According to one embodiment of the invention, the angle of the tip of the guide rotor blade is 0 ° to 10 °, and the angle of the root of the guide rotor blade is 0 ° to 10 ° greater than the angle of the tip.

According to an embodiment of the invention, the number of the guide rotor blades of the guide rotor blade row is 0.5 to 1.0 times the number of the rotor blades of the rotor blade row.

According to an embodiment of the present invention, when the number of the guide rotor blades of the guide rotor blade row is 0.5 times or 1 time the number of the rotor blades of the rotor blade row, a ratio of an axial distance between a leading edge of the rotor blade and a trailing edge of the guide rotor blade to an axial distance between the leading edge and the trailing edge of the guide rotor blade is-0.1 to 0.2;

when the number of the guide flow rotor blades of the guide rotor blade row is equal to the ratio of the number of the rotor blades of the rotor blade row to 0.5 or 1, the ratio of the axial distance between the front edge of the rotor blade and the tail edge of the guide rotor blade to the axial distance between the front edge and the tail edge of the guide rotor blade is 0.05-0.2.

According to an embodiment of the present invention, further comprising a compressor case covering the rotor and the rotor blade row, a stator blade row being arranged in a circumferential direction of the compressor case, the stator blade row including a plurality of stator blades arranged in a circumferential direction of the rotary shaft;

in the direction of the air flow in the axial compressor, the guide rotor blade row, i.e., the rotor blade row, is arranged in front of the stator blade row.

According to the axial flow compressor provided by the invention, the guide rotor blade row is arranged in front of the rotor blade row, so that the two rows of blades rotate in the same direction and at the same speed, the rotor blades are always ensured to work under a designed attack angle, the axial flow compressor always works in an optimal state, the possibility of rotating stall is effectively reduced, the margin of the axial flow compressor is improved, and the efficiency of the axial flow compressor under an off-design working condition is improved.

It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

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 principle of the invention. In the drawings:

fig. 1 shows a partial cross-sectional schematic view of a prior art axial flow compressor.

FIG. 2 shows a schematic cross-sectional view of each blade in the direction of the blade height according to an embodiment of the invention.

FIG. 3 shows a schematic cross-sectional view of each blade in the direction of the blade height according to an embodiment of the invention.

FIG. 4 shows a schematic cross-sectional view of each blade in the direction of the blade height according to an embodiment of the invention.

Wherein the above figures essentially include the following reference numerals:

axial compressor 100 rotor 110

Drum 111

rotor blades

112, 220, 320', 420

Bucket tip 113 and bucket 114

Compressor case outer 120

stator blades

121, 230, 330', 430

Camber

line

211, 221 of

guide rotor blade

210, 310', 410

Leaf backs

212, 222,

leaf basins

213, 223

Preparation method 300

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. It is to be understood that the embodiments described are only a few embodiments of the present application and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the application, 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 application.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

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 application 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.

In the description of the present application, it is to be understood that the orientation or positional relationship indicated by the directional terms such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal" and "top, bottom", etc., are generally based on the orientation or positional relationship shown in the drawings, and are used for convenience of description and simplicity of description only, and in the case of not making a reverse description, these directional terms do not indicate and imply that the device or element being referred to must have a particular orientation or be constructed and operated in a particular orientation, and therefore, should not be considered as limiting the scope of the present application; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.

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.

It should be noted that the terms "first", "second", and the like are used to define the components, and are only used for convenience of distinguishing the corresponding components, and the terms have no special meanings unless otherwise stated, and therefore, the scope of protection of the present application is not to be construed as being limited. Further, although the terms used in the present application are selected from publicly known and used terms, some of the terms mentioned in the specification of the present application may be selected by the applicant at his or her discretion, the detailed meanings of which are described in relevant parts of the description herein. Further, it is required that the present application is understood not only by the actual terms used but also by the meaning of each term lying within.

Fig. 1 shows a partial cross-sectional schematic view of a prior art axial flow compressor. As shown, the conventional axial compressor 100 includes a rotor 110 and a compressor case 120 covering the rotor 110, the compressor case 120 corresponding to a stator opposite to the rotor 110, the rotor 110 rotating along a rotation axis thereof inside the compressor case 120. The compressor outer case 120 is a non-rotating part of the axial compressor 100, and the compressor outer case 120 is provided with stator blades 121, and a plurality of stator blades 121 are arranged in the circumferential direction of the rotating shaft of the rotor 110 to form a stator blade row. The rotor 110 includes a drum 111, and rotor blades 112 are arranged on the drum 111. The rotor blades 112 are arranged in plural in the circumferential direction of the rotation shaft of the rotor 110 to form a rotor blade row. The stator blade rows and the rotor blade rows are arranged in a staggered manner at intervals in the circumferential direction of the rotating shaft. The portion of rotor blade 112 away from the axis of rotor 110 is referred to as a blade tip 113, the portion of rotor blade 112 near the axis of rotor 110 is referred to as a blade root 114, the portion of rotor blade 112 near compressor case 120 in FIG. 1 is referred to as a blade tip 113 of rotor blade 112, and the portion of rotor blade 112 near the blade root 114 of rotor blade 112 of drum 111.

The present invention provides an axial flow compressor which comprises a rotor as a rotating shaft and a rotor blade row which is installed on the rotor and is configured along the circumferential direction of the rotating shaft, wherein the rotor blade row comprises a plurality of rotor blades configured along the circumferential direction of the rotating shaft. The axial flow compressor further includes a guide rotor blade row installed on the rotor and configured along a circumferential direction of the rotation shaft, the guide rotor blade row including a plurality of guide rotor blades configured along the circumferential direction of the rotation shaft. FIG. 2 shows a schematic cross-sectional view of each blade in the direction of the blade height according to an embodiment of the invention. The blade height direction is the rotor radial direction. As shown, the X direction is substantially parallel to the axial direction of the rotation shaft of the rotor, and the Y direction indicates the blade rotation direction. The row of guide rotor blades is arranged before the row of rotor blades in the direction of the air flow in the axial flow compressor, where "before" refers to a position relatively upstream in the air flow of the axial flow compressor. The camber line 211 of the blade airfoil cross section of the guide rotor blade 210 is curved in the opposite direction to the camber line 221 of the blade airfoil cross section of the rotor blade 220. The guide rotor blades 210 and the rotor blades 220 rotate at the same speed in the same direction. The guide rotor blade row and the subsequent rotor blade row are arranged in series along the axial direction, and the two rows of blades rotate at the same speed in the same direction, so that the airflow direction of the inlet of the rotor blade 220 behind the guide rotor blade 210 is always kept basically consistent with the geometric direction of the inlet of the rotor blade, the rotor blade 220 is ensured to always work under a designed attack angle, the axial flow compressor is always operated in the best state, the possibility of rotating stall is effectively reduced, the margin of the axial flow compressor is improved, and the efficiency of the axial flow compressor under the non-designed working condition is improved.

Preferably, the inlet geometry angle of the guide rotor blade is not smaller than the outlet geometry angle, with the frontal line as the angle defining the reference. Referring to fig. 2, the leading edge a to the trailing edge B of the guide rotor blade 210 forms a blade back 212 and a blade basin 213 of the guide rotor blade. The direction of rotation of the guide rotor blade 210 is along the Y-axis from the basin to the back of the blade of the guide rotor blade 210. The leading edge C to the trailing edge D of the rotor blade 220 form a blade back 222 and a blade basin 223 of the rotor blade 220. The direction of rotation of the rotor blade 220 is along the Y-axis from the blade back to the blade basin of the rotor blade 220. An included angle between a tangent line of the camber line 211 of each guide rotor blade 210 at the leading edge point a and a connecting line (frontal line AA) of the leading edges of two adjacent guide rotor blades 210 is an inlet geometric angle α, an included angle between a tangent line of the camber line 211 at the trailing edge point B and a connecting line (frontal line BB) of the trailing edges of two adjacent guide rotor blades 210 is an outlet geometric angle β, and the inlet geometric angle α is not smaller than the outlet geometric angle β.

Preferably, the angle of the guide rotor blade 210 is 0 to 20 °. The guide rotor blades 210 extend outward along the axis of the rotation shaft of the rotor, and the tip portions thereof are relatively distant from the axis of the rotation shaft than the root portions thereof. Referring to fig. 2, the reference is defined by the frontal line as the angle, and the bend angle θ is the difference between the inlet geometry angle α and the outlet geometry angle β. More preferably, the angle of the blade tip of the guide rotor blade 210 is 0-10 °, and the angle of the blade root is 0-10 ° greater than the angle of the blade tip

Preferably, the number of the guide rotor blades 210 of the guide rotor blade row is 0.5 to 1.0 times the number of the rotor blades 220 of the rotor blade row. More preferably, referring to fig. 2, the ratio of the axial distance X2 between the leading edge C of the rotor blade 220 and the trailing edge B of the guide rotor blade 210 to the axial distance X1 from the leading edge a to the trailing edge B of the guide rotor blade 210 is a. When the number of the guide rotor blades 210 of the guide rotor blade row is 0.5 times or 1 time of the number of the rotor blades 220 of the rotor blade row, the value range of the ratio A is-0.1-0.2. And when the ratio of the number of the guide rotor blades 210 of the guide rotor blade row to the number of the guide rotor blades 210 of the rotor blade row is not equal to 0.5 or 1, the value range of the ratio A is 0.05-0.2.

Preferably, the axial flow compressor further includes a compressor case covering the rotor and the row of rotor blades. A stator blade row including a plurality of stator blades arranged in a circumferential direction of a rotating shaft is arranged in a circumferential direction of a compressor outer case. The stator blade row is disposed behind the rotor blade row in the direction of the air flow in the axial flow compressor, and "behind" here refers to a position relatively downstream in the air flow of the axial flow compressor. Referring to fig. 2, a guide rotor blade 210, a rotor blade 220, and a stator blade 230 are sequentially arranged in an air flow direction within an axial compressor.

Preferably, a plurality of rows of rotor blades and a corresponding plurality of rows of guide rotor blades are arranged on the rotor along the circumferential direction of the rotating shaft, and each row of guide rotor blades is arranged in front of each row of rotor blades in the airflow direction in the axial flow compressor. Conventionally, a row of rotor blades followed by a row of stator blades is referred to as a stage of an axial compressor. In each such stage of the axial compressor, a row of guide rotor blades may be arranged in front of the row of rotor blades. FIG. 3 shows a schematic cross-sectional view of each blade in the direction of the blade height according to an embodiment of the invention. As shown in fig. 3, the X direction is substantially parallel to the axial direction of the rotation shaft of the rotor, and the Y direction indicates the blade rotation direction. Two stages of blade rows are arranged in sequence in the airflow direction in the double-stage axial flow compressor. The first stage includes a guide rotor blade row, a rotor blade row and a stator blade row, and correspondingly, the guide rotor blades 310, the rotor blades 320 and the stator blades 330 are sequentially arranged in the airflow direction in the axial flow compressor, the second stage after the first stage also includes the guide rotor blade row, the rotor blade row and the stator blade row, and correspondingly, the guide rotor blades 310 ', the rotor blades 320 ' and the stator blades 330 ' are sequentially arranged in the airflow direction in the axial flow compressor. The guide rotor blades 310, 310 'can automatically maintain the inlet airflow method of the following rotor blades 320, 320' substantially unchanged,

FIG. 4 shows a schematic cross-sectional view of each blade in the direction of the blade height according to an embodiment of the invention. In this embodiment, the X direction is substantially parallel to the axial direction of the rotation shaft of the rotor, and the Y direction indicates the blade rotation direction. The single-stage axial flow compressor is sequentially provided with a guide rotor blade row, a rotor blade row and a stator blade row along the axis direction of a rotating shaft of a rotor. Accordingly, a guide rotor blade 410, a rotor blade 420, and a stator blade 430 are arranged. The camber of the root of the guide rotor blade 410 is 10 °, the camber of the tip thereof is 0 °, the guide rotor blade row and the subsequent rotor blade row have the same number of blades, and the ratio of the axial distance between the leading edge of the rotor blade 420 and the trailing edge of the guide rotor blade 410 to the axial distance between the leading edge and the trailing edge of the guide rotor blade 410 is-0.1.

In the embodiment illustrated in fig. 3, in the first stage of the two-stage axial compressor, the root of the guide rotor blade 310 is bent by 13 °, and the tip of the guide rotor blade is bent by 5 °. The number of the blades of the guide rotor blade row is 0.5 times of the number of the blades of the subsequent rotor blade row, and the ratio of the relative axial distance of the two blade rows is 0.05. In the second stage, the guiding rotor blade 310' has a 20 ° root curvature and a 10 ° tip curvature. The number of blades of a guide rotor blade row may be 36, the number of blades of a subsequent rotor blade row may be 54, and the ratio of the relative axial distances of the two blade rows is 0.1.

Another embodiment is a three stage axial compressor (not shown). A guide rotor blade row is arranged in front of the rotor blade row of each stage of the three-stage axial flow compressor. In the first stage, the camber of the blade root of the guide rotor blade is 8 degrees, the camber of the blade tip is 8 degrees, the number of the blades of the guide rotor blade row is 0.8 times of the number of the blades of the subsequent rotor blade row, and the ratio of the relative axial distance of the two blade rows is 0.15. In the second stage, the camber of the blade root of the guide rotor blade is 15 degrees, the camber of the blade tip is 10 degrees, the number of the blades of the guide rotor blade row is 1 time of that of the blades of the subsequent rotor blade row, and the ratio of the relative axial distance of the two blade rows is-0.05. In the third stage, the camber of the blade root of the guide rotor blade is 18 degrees, the camber of the blade tip is 8 degrees, the number of the blades of the guide rotor blade row is 1 time of that of the blades of the subsequent rotor blade row, and the relative axial distance ratio of the two blade rows is 0.0.

According to the axial flow compressor provided by the invention, the guide rotor blade row is arranged in front of the rotor blade row, so that the guide rotor blades can automatically keep the airflow direction of the inlet of the subsequent rotor blade basically unchanged, any additional adjusting mechanism is not required to be added, the pneumatic stability of the axial flow compressor can be effectively improved, and the axial flow compressor can always work in the optimal state.

It will be apparent to those skilled in the art that various modifications and variations can be made to the above-described exemplary embodiments of the present invention without departing from the spirit and scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

Claims

1. An axial flow compressor having a rotor as a rotating shaft and a rotor blade row mounted on the rotor and arranged in a circumferential direction of the rotating shaft, the rotor blade row including a plurality of rotor blades arranged in the circumferential direction of the rotating shaft;

2. The axial compressor of claim 1, wherein an inlet geometric angle of the guide rotor blade is not less than an outlet geometric angle with respect to a frontal line as an angle defining a reference.

3. The axial flow compressor as claimed in claim 2, wherein the guide rotor blades have a bending angle of 0 ° to 20 °.

4. The axial flow compressor as claimed in claim 3, wherein the tip of the guide rotor blade has a bend angle of 0 ° to 10 °, and the root of the guide rotor blade has a bend angle of 0 ° to 10 ° greater than the tip of the guide rotor blade.

5. The axial flow compressor of claim 1, wherein the number of the guide rotor blades of the guide rotor blade row is 0.5 to 1.0 times the number of the rotor blades of the rotor blade row.

6. The axial flow compressor according to claim 5, wherein when the number of the guide rotor blades of the guide rotor blade row is 0.5 times or 1 times the number of the rotor blades of the rotor blade row, a ratio of an axial distance between a leading edge of the rotor blade and a trailing edge of the guide rotor blade to an axial distance from the leading edge to the trailing edge of the guide rotor blade is-0.1 to 0.2;

7. The axial compressor of claim 1, further comprising a compressor case covering the rotor and the rotor blade row, a stator blade row being arranged in a circumferential direction of the compressor case, the stator blade row including a plurality of stator blades arranged in a circumferential direction of the rotating shaft;

the guide rotor blade row and the rotor blade row are arranged in front of the stator blade row in an air flow direction in the axial flow compressor.